1
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Pinto JL, Marshall CR, Nesbitt SJ, Varajão de Latorre D. Quantitative evidence for dimorphism suggests sexual selection in the maxillary caniniform process of Placerias hesternus. PLoS One 2024; 19:e0297894. [PMID: 38820280 PMCID: PMC11142433 DOI: 10.1371/journal.pone.0297894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 01/16/2024] [Indexed: 06/02/2024] Open
Abstract
Placerias hesternus, a Late Triassic dicynodont, is one of the last megafaunal synapsids of the Mesozoic. The species has a tusk-like projection on its maxillary bone, known as the caniniform process. This process has been hypothesized to be sexually dimorphic since the 1950s, however this claim has not been thoroughly investigated quantitatively. Here, we examined maxillae, premaxillae, quadrates, and fibulae from a single population from the Placerias Quarry in the Blue Mesa Member of the Chinle Formation, near St. Johns, Arizona, USA to determine if the caniniform process is dimorphic. We made a total of 25 measurements from the four bones and used a maximum likelihood framework to compare the fit of unimodal versus bimodal distributions for each set of measurements. Our results from complete maxillae reveal that the caniniform process has two distinct morphs, with a shorter and longer form. This interpretation is substantiated both by strong statistical support for bimodal distribution of caniniform lengths, and by clustering analysis that clearly distinguishes two morphs for the maxillae. Clustering analysis also shows support for potential dimorphism in the shape of the quadrate. However, no measurements from elements other than the maxilla have a strong likelihood of bimodal distribution. These results support the long-standing hypothesis that the caniniform in Placerias was dimorphic. Alternative explanations to sexual dimorphism that could account for the dimorphism among these fossils include the presence of juveniles in the sample or time-averaged sampling of a chronospecies, but both have been previously rejected for the Placerias Quarry population. The lack of strong dimorphism in non-maxilla elements and increased variation in caniniform length of the large-caniniform morph suggest that the caniniform is a secondary sexual trait, possibly used in intraspecific competition.
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Affiliation(s)
- James L. Pinto
- Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, California, United States of America
| | - Charles R. Marshall
- Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, California, United States of America
| | - Sterling J. Nesbitt
- Department of Geosciences, Virginia Tech, Blacksburg, Virginia, United States of America
| | - Daniel Varajão de Latorre
- Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, California, United States of America
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2
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Svenning JC, Buitenwerf R, Le Roux E. Trophic rewilding as a restoration approach under emerging novel biosphere conditions. Curr Biol 2024; 34:R435-R451. [PMID: 38714176 DOI: 10.1016/j.cub.2024.02.044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2024]
Abstract
Rewilding is a restoration approach that aims to promote self-regulating complex ecosystems by restoring non-human ecological processes while reducing human control and pressures. Rewilding is forward-looking in that it aims to enhance functionality for biodiversity, accepting and indeed promoting the dynamic nature of ecosystems, rather than fixating on static composition or structure. Rewilding is thus especially relevant in our epoch of increasingly novel biosphere conditions, driven by strong human-induced global change. Here, we explore this hypothesis in the context of trophic rewilding - the restoration of trophic complexity mediated by wild, large-bodied animals, known as 'megafauna'. This focus reflects the strong ecological impacts of large-bodied animals, their widespread loss during the last 50,000 years and their high diversity and ubiquity in the preceding 50 million years. Restoring abundant, diverse, wild-living megafauna is expected to promote vegetation heterogeneity, seed dispersal, nutrient cycling and biotic microhabitats. These are fundamental drivers of biodiversity and ecosystem function and are likely to gain importance for maintaining a biodiverse biosphere under increasingly novel ecological conditions. Non-native megafauna species may contribute to these effects as ecological surrogates of extinct species or by promoting ecological functionality within novel assemblages. Trophic rewilding has strong upscaling potential via population growth and expansion of wild fauna. It is likely to facilitate biotic adaptation to changing climatic conditions and resilience to ecosystem collapse, and to curb some negative impacts of globalization, notably the dominance of invasive alien plants. Finally, we discuss the complexities of realizing the biodiversity benefits that trophic rewilding offers under novel biosphere conditions in a heavily populated world.
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Affiliation(s)
- Jens-Christian Svenning
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO), Department of Biology, Aarhus University, Ny Munkegade 114, DK-8000 Aarhus C, Denmark.
| | - Robert Buitenwerf
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO), Department of Biology, Aarhus University, Ny Munkegade 114, DK-8000 Aarhus C, Denmark
| | - Elizabeth Le Roux
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO), Department of Biology, Aarhus University, Ny Munkegade 114, DK-8000 Aarhus C, Denmark; Department of Zoology and Entomology, Faculty of Natural and Agricultural Sciences, Mammal Research Institute, University of Pretoria, Pretoria 0028, South Africa
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3
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Ritwika VPS, Gopinathan A, Yeakel JD. Beyond the kill: The allometry of predation behaviours among large carnivores. J Anim Ecol 2024; 93:554-566. [PMID: 38459609 DOI: 10.1111/1365-2656.14070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 02/06/2024] [Indexed: 03/10/2024]
Abstract
The costs of foraging can be high while also carrying significant risks, especially for consumers feeding at the top of the food chain. To mitigate these risks, many predators supplement active hunting with scavenging and kleptoparasitic behaviours, in some cases specializing in these alternative modes of predation. The factors that drive differential utilization of these tactics from species to species are not well understood. Here, we use an energetics approach to investigate the survival advantages of hunting, scavenging and kleptoparasitism as a function of predator, prey and potential competitor body sizes for terrestrial mammalian carnivores. The results of our framework reveal that predator tactics become more diverse closer to starvation, while the deployment of scavenging and kleptoparasitism is strongly constrained by the ratio of predator to prey body size. Our model accurately predicts a behavioural transition away from hunting towards alternative modes of predation with increasing prey size for predators spanning an order of magnitude in body size, closely matching observational data across a range of species. We then show that this behavioural boundary follows an allometric power-law scaling relationship where the predator size scales with an exponent nearing 3/4 with prey size, meaning that this behavioural switch occurs at relatively larger threshold prey body size for larger carnivores. We suggest that our approach may provide a holistic framework for guiding future observational efforts exploring the diverse array of predator foraging behaviours.
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Affiliation(s)
- V P S Ritwika
- Department of Physics, UC Merced, Merced, California, USA
- Department of Communication, UCLA, Los Angeles, California, USA
- Life and Environmental Sciences, UC Merced, Merced, California, USA
| | | | - Justin D Yeakel
- Life and Environmental Sciences, UC Merced, Merced, California, USA
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4
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de Magalhães JP. The longevity bottleneck hypothesis: Could dinosaurs have shaped ageing in present-day mammals? Bioessays 2024; 46:e2300098. [PMID: 38018264 DOI: 10.1002/bies.202300098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 11/01/2023] [Accepted: 11/02/2023] [Indexed: 11/30/2023]
Abstract
The evolution and biodiversity of ageing have long fascinated scientists and the public alike. While mammals, including long-lived species such as humans, show a marked ageing process, some species of reptiles and amphibians exhibit very slow and even the absence of ageing phenotypes. How can reptiles and other vertebrates age slower than mammals? Herein, I propose that evolving during the rule of the dinosaurs left a lasting legacy in mammals. For over 100 million years when dinosaurs were the dominant predators, mammals were generally small, nocturnal, and short-lived. My hypothesis is that such a long evolutionary pressure on early mammals for rapid reproduction led to the loss or inactivation of genes and pathways associated with long life. I call this the 'longevity bottleneck hypothesis', which is further supported by the absence in mammals of regenerative traits. Although mammals, such as humans, can evolve long lifespans, they do so under constraints dating to the dinosaur era.
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Affiliation(s)
- João Pedro de Magalhães
- Genomics of Ageing and Rejuvenation Lab, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
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5
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Hellert SM, Grossnickle DM, Lloyd GT, Kammerer CF, Angielczyk KD. Derived faunivores are the forerunners of major synapsid radiations. Nat Ecol Evol 2023; 7:1903-1913. [PMID: 37798433 DOI: 10.1038/s41559-023-02200-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 08/06/2023] [Indexed: 10/07/2023]
Abstract
Evolutionary radiations generate most of Earth's biodiversity, but are there common ecomorphological traits among the progenitors of radiations? In Synapsida (the mammalian total group), 'small-bodied faunivore' has been hypothesized as the ancestral state of most major radiating clades, but this has not been quantitatively assessed across multiple radiations. To examine macroevolutionary patterns in a phylogenetic context, we generated a time-calibrated metaphylogeny ('metatree') comprising 1,888 synapsid species from the Carboniferous through the Eocene (305-34 Ma) based on 269 published character matrices. We used comparative methods to investigate body size and dietary evolution during successive synapsid radiations. Faunivory is the ancestral dietary regime of each major synapsid radiation, but relatively small body size is only established as the common ancestral state of radiations near the origin of Mammaliaformes in the Late Triassic. The faunivorous ancestors of synapsid radiations typically have numerous novel characters compared with their contemporaries, and these derived traits may have helped them to survive faunal turnover events and subsequently radiate.
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Affiliation(s)
- Spencer M Hellert
- Negaunee Integrative Research Center, Field Museum of Natural History, Chicago, IL, USA.
- Department of Science and Mathematics, Columbia College Chicago, Chicago, IL, USA.
| | - David M Grossnickle
- Department of Biology, University of Washington, Seattle, WA, USA
- Natural Sciences Department, Oregon Institute of Technology, Klamath Falls, OR, USA
| | | | | | - Kenneth D Angielczyk
- Negaunee Integrative Research Center, Field Museum of Natural History, Chicago, IL, USA
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6
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Pahl CC, Ruedas LA. Big boned: How fat storage and other adaptations influenced large theropod foraging ecology. PLoS One 2023; 18:e0290459. [PMID: 37910492 PMCID: PMC10619836 DOI: 10.1371/journal.pone.0290459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 08/08/2023] [Indexed: 11/03/2023] Open
Abstract
Dinosaur foraging ecology has been the subject of scientific interest for decades, yet much of what we understand about it remains hypothetical. We wrote an agent-based model (ABM) to simulate meat energy sources present in dinosaur environments, including carcasses of giant sauropods, along with living, huntable prey. Theropod dinosaurs modeled in this environment (specifically allosauroids, and more particularly, Allosaurus Marsh, 1877) were instantiated with heritable traits favorable to either hunting success or scavenging success. If hunter phenotypes were more reproductively successful, their traits were propagated into the population through their offspring, resulting in predator specialists. If selective pressure favored scavenger phenotypes, the population would evolve to acquire most of their calories from carrion. Data generated from this model strongly suggest that theropods in sauropod-dominated systems evolved to detect carcasses, consume and store large quantities of fat, and dominate carcass sites. Broadly speaking, selective forces did not favor predatory adaptations, because sauropod carrion resource pools, as we modeled them, were too profitable for prey-based resource pools to be significant. This is the first research to test selective pressure patterns in dinosaurs, and the first to estimate theropod mass based on metabolic constraints.
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Affiliation(s)
- Cameron C. Pahl
- Department of Biology and Museum of Vertebrate Biology, Science Research and Teaching Center—246, Portland State University, Portland, Oregon, United States of America
| | - Luis A. Ruedas
- Department of Biology and Museum of Vertebrate Biology, Science Research and Teaching Center—246, Portland State University, Portland, Oregon, United States of America
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7
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Farina BM, Godoy PL, Benson RBJ, Langer MC, Ferreira GS. Turtle body size evolution is determined by lineage-specific specializations rather than global trends. Ecol Evol 2023; 13:e10201. [PMID: 37384241 PMCID: PMC10293707 DOI: 10.1002/ece3.10201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 05/26/2023] [Accepted: 06/01/2023] [Indexed: 06/30/2023] Open
Abstract
Organisms display a considerable variety of body sizes and shapes, and macroevolutionary investigations help to understand the evolutionary dynamics behind such variations. Turtles (Testudinata) show great body size disparity, especially when their rich fossil record is accounted for. We explored body size evolution in turtles, testing which factors might influence the observed patterns and evaluating the existence of long-term directional trends. We constructed the most comprehensive body size dataset for the group to date, tested for correlation with paleotemperature, estimated ancestral body sizes, and performed macroevolutionary model-fitting analyses. We found no evidence for directional body size evolution, even when using very flexible models, thereby rejecting the occurrence of Cope's rule. We also found no significant effect of paleotemperature on overall through-time body size patterns. In contrast, we found a significant influence of habitat preference on turtle body size. Freshwater turtles display a rather homogeneous body size distribution through time. In contrast, terrestrial and marine turtles show more pronounced variation, with terrestrial forms being restricted to larger body sizes, up to the origin of testudinids in the Cenozoic, and marine turtles undergoing a reduction in body size disparity after the extinctions of many groups in the mid-Cenozoic. Our results, therefore, suggest that long-term, generalized patterns are probably explained by factors specific to certain groups and related at least partly to habitat use.
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Affiliation(s)
- Bruna M. Farina
- Department of BiologyUniversity of FribourgFribourgSwitzerland
- Swiss Institute of BioinformaticsFribourgSwitzerland
- Laboratório de Paleontologia de Ribeirão PretoUniversidade de São PauloRibeirão PretoBrazil
| | - Pedro L. Godoy
- Laboratório de Paleontologia de Ribeirão PretoUniversidade de São PauloRibeirão PretoBrazil
- Department of Anatomical SciencesStony Brook UniversityStony BrookNew YorkUSA
| | - Roger B. J. Benson
- Division of PaleontologyAmerican Museum of Natural HistoryNew YorkNew YorkUSA
| | - Max C. Langer
- Laboratório de Paleontologia de Ribeirão PretoUniversidade de São PauloRibeirão PretoBrazil
| | - Gabriel S. Ferreira
- Senckenberg Centre for Human Evolution and Palaeoenvironment (HEP)Eberhard Karls Universität TübingenTübingenGermany
- Fachbereich GeowissenschaftenEberhard Karls Universität TübingenTübingenGermany
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8
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Sanisidro O, Mihlbachler MC, Cantalapiedra JL. A macroevolutionary pathway to megaherbivory. Science 2023; 380:616-618. [PMID: 37167399 DOI: 10.1126/science.ade1833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 04/04/2023] [Indexed: 05/13/2023]
Abstract
Several scenarios have been proposed to explain rapid net size increases in some early Cenozoic mammalian lineages: sustained and gradual directional change, successive occupation of adaptive zones associated with progressively larger body sizes, and nondirectional evolution associated with branching events in combination with higher diversification potential of the larger lineages. We test these hypotheses in brontotheres, which are among the first radiations of mammals that consistently evolved multitonne sizes. Body-mass evolution in brontotheres mainly occurred during speciation and had no preferential direction. Long-term directional change stemmed from the higher survival of larger lineages in less-saturated herbivore guilds. Our study emphasizes the role of differential species proliferation in explaining the long-term phenotypic trends observed in the fossil record, which are more than an accumulation of steady microevolutionary changes.
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Affiliation(s)
- Oscar Sanisidro
- Global Change Ecology and Evolution Research Group (GloCEE), Department of Life Sciences, Universidad de Alcalá, 28805 Alcalá de Henares, Madrid, Spain
| | - Matthew C Mihlbachler
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
- Division of Paleontology, American Museum of Natural History, New York, NY 10024, USA
| | - Juan L Cantalapiedra
- Global Change Ecology and Evolution Research Group (GloCEE), Department of Life Sciences, Universidad de Alcalá, 28805 Alcalá de Henares, Madrid, Spain
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9
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D'Emic MD. The evolution of maximum terrestrial body mass in sauropod dinosaurs. Curr Biol 2023; 33:R349-R350. [PMID: 37160089 DOI: 10.1016/j.cub.2023.02.067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/21/2023] [Indexed: 05/11/2023]
Abstract
The long-necked dinosaurs, sauropods, are famous for their extreme body sizes, evolving body masses several times greater than the next-heaviest terrestrial animals, elephant-like and rhinoceros- like mammals and 'duck-billed' dinosaurs. The pace of sauropod discovery has been exponential in recent decades, resulting in the recognition of sauropods as a global, ecologically diverse group of herbivorous dinosaurs comprising over 250 known species1. However, limitations due to missing data from their patchy fossil record have so far limited studies of sauropod body-size evolution to less than half their known diversity1. Here, I present models to confidently predict unknown limb-bone measurements in sauropods, resulting in a dataset 50% larger than previously assembled. Leveraging the emerging consilience among body mass estimation methods for fossil tetrapods, I then map sauropod body mass evolution through time in a phylogenetic context. Likelihood-based ancestral state reconstruction reveals that sauropods convergently surpassed maximum terrestrial mammalian body mass at least three dozen times over the course of 100 million years, on at least six landmasses and in at least five ecomorphologically disparate clades. Sauropod maximum body mass rapidly increased early in their evolutionary history from under 5,000 kg before levelling off around 40,000 kg (with notable exceptions)2, in a pattern similar to that observed in terrestrial mammals3.
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Affiliation(s)
- Michael Daniel D'Emic
- Department of Biology, Adelphi University, 1 South Avenue, Garden City, NY 11530, USA.
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10
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Gnawing pressure led to the expansion of JAZ genes in angiosperms. Int J Biol Macromol 2023; 230:123165. [PMID: 36623623 DOI: 10.1016/j.ijbiomac.2023.123165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 12/06/2022] [Accepted: 01/03/2023] [Indexed: 01/09/2023]
Abstract
A long-standing problem in evolutionary biology is why some populations differentiate into many species while the majority do not. Angiosperms is an excellent group for investigating this problem because their diversity is unevenly distributed in space and phylogeny. Plant hormone participates in growth, development and defense. However, jasmonic acid (JA) was the only hormone response to bites. We first searched jasmonate ZIM-domain (JAZ), AUXIN/INDOLE ACETIC ACID (IAA / aux), PYR/PYL/RCAR (PYL), DELLA, and SUPPRESSOR OF MAX2 1-like (SMAX) in 272 plant species. We found the gene number change trends were consistent with origination rates and species numbers of angiosperms. So, 26 representative species were selected as an example for further analysis. The results showed JAZ had experienced two lineage-specific gene expansion events in angiosperms, which coincided with increases in mammalian body size and dental diversity. The proliferation of large herbivores as a results of mammalian prosperity after dinosaur extinction may be related to angiosperm evolution and bursting. The proliferation of large herbivores as the result of mammalian prosperity after the extinction of the dinosaurs was related to angiosperm evolution and bursting. Overall, our study uncovered a previously unknown co-evolution mechanism in terrestrial plants exposed to extreme environmental conditions.
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11
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Changes in bee functional traits at community and intraspecific levels along an elevational gradient in a Mexical-type scrubland. Oecologia 2022; 200:145-158. [PMID: 36053349 DOI: 10.1007/s00442-022-05248-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 08/22/2022] [Indexed: 10/14/2022]
Abstract
Understanding the causes of morphological variation of organisms along climatic gradients has been a central challenge in ecological research. We studied the variation of community weighted mean (CWM) and two functional diversity metrics (Rao-Q and functional richness) computed for five morphological traits of wild bees (Hymenoptera: Apoidea) related to thermal performance (namely body size, relative appendage length and hairiness), at community and interspecific levels, along an elevation gradient in a Mexical-type scrubland. At the community level we found a decreasing CWM of body size pattern with increasing elevation which is consistent with the species-energy theory (and contrary to Bergmann's rule). We also found an increase in the CWM of relative tibia length, which is contrary to Allen's rule. Additionally, we found an increase in the CWM of relative hair length towards high levels of elevation, which would be consistent with the hypothesis that hairiness plays an important role as thermal insulation. We found that functional diversity was larger at low elevations with respect to high elevation for body size and hair length, which could imply that highland communities were more sensitive towards environmental changes than lowland communities. Overall, at intraspecific level, most of species showed no pattern for any of the traits along the elevation gradient. Future research should provide further evidence on the possible behavioral or physiological mechanisms behind it.
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12
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Funston GF, dePolo PE, Sliwinski JT, Dumont M, Shelley SL, Pichevin LE, Cayzer NJ, Wible JR, Williamson TE, Rae JWB, Brusatte SL. The origin of placental mammal life histories. Nature 2022; 610:107-111. [PMID: 36045293 DOI: 10.1038/s41586-022-05150-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 07/27/2022] [Indexed: 11/09/2022]
Abstract
After the end-Cretaceous extinction, placental mammals quickly diversified1, occupied key ecological niches2,3 and increased in size4,5, but this last was not true of other therians6. The uniquely extended gestation of placental young7 may have factored into their success and size increase8, but reproduction style in early placentals remains unknown. Here we present the earliest record of a placental life history using palaeohistology and geochemistry, in a 62 million-year-old pantodont, the clade including the first mammals to achieve truly large body sizes. We extend the application of dental trace element mapping9,10 by 60 million years, identifying chemical markers of birth and weaning, and calibrate these to a daily record of growth in the dentition. A long gestation (approximately 7 months), rapid dental development and short suckling interval (approximately 30-75 days) show that Pantolambda bathmodon was highly precocial, unlike non-placental mammals and known Mesozoic precursors. These results demonstrate that P. bathmodon reproduced like a placental and lived at a fast pace for its body size. Assuming that P. bathmodon reflects close placental relatives, our findings suggest that the ability to produce well-developed, precocial young was established early in placental evolution, and that larger neonate sizes were a possible mechanism for rapid size increase in early placentals.
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Affiliation(s)
- Gregory F Funston
- School of GeoSciences, University of Edinburgh, Edinburgh, UK. .,Department of Natural History, Royal Ontario Museum, Toronto, Ontario, Canada.
| | - Paige E dePolo
- School of GeoSciences, University of Edinburgh, Edinburgh, UK
| | - Jakub T Sliwinski
- School of Earth and Environmental Sciences, University of St Andrews, St Andrews, UK
| | - Matthew Dumont
- School of Earth and Environmental Sciences, University of St Andrews, St Andrews, UK
| | - Sarah L Shelley
- School of GeoSciences, University of Edinburgh, Edinburgh, UK
| | | | - Nicola J Cayzer
- School of GeoSciences, University of Edinburgh, Edinburgh, UK
| | - John R Wible
- Carnegie Museum of Natural History, Pittsburgh, PA, USA
| | | | - James W B Rae
- School of Earth and Environmental Sciences, University of St Andrews, St Andrews, UK
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13
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Harrison JF, Biewener A, Bernhardt JR, Burger JR, Brown JH, Coto ZN, Duell ME, Lynch M, Moffett ER, Norin T, Pettersen AK, Smith FA, Somjee U, Traniello JFA, Williams TM. White Paper: An Integrated Perspective on the Causes of Hypometric Metabolic Scaling in Animals. Integr Comp Biol 2022; 62:icac136. [PMID: 35933126 PMCID: PMC9724154 DOI: 10.1093/icb/icac136] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 04/16/2022] [Accepted: 05/19/2022] [Indexed: 11/15/2022] Open
Abstract
Larger animals studied during ontogeny, across populations, or across species, usually have lower mass-specific metabolic rates than smaller animals (hypometric scaling). This pattern is usually observed regardless of physiological state (e.g. basal, resting, field, maximally-active). The scaling of metabolism is usually highly correlated with the scaling of many life history traits, behaviors, physiological variables, and cellular/molecular properties, making determination of the causation of this pattern challenging. For across-species comparisons of resting and locomoting animals (but less so for across populations or during ontogeny), the mechanisms at the physiological and cellular level are becoming clear. Lower mass-specific metabolic rates of larger species at rest are due to a) lower contents of expensive tissues (brains, liver, kidneys), and b) slower ion leak across membranes at least partially due to membrane composition, with lower ion pump ATPase activities. Lower mass-specific costs of larger species during locomotion are due to lower costs for lower-frequency muscle activity, with slower myosin and Ca++ ATPase activities, and likely more elastic energy storage. The evolutionary explanation(s) for hypometric scaling remain(s) highly controversial. One subset of evolutionary hypotheses relies on constraints on larger animals due to changes in geometry with size; for example, lower surface-to-volume ratios of exchange surfaces may constrain nutrient or heat exchange, or lower cross-sectional areas of muscles and tendons relative to body mass ratios would make larger animals more fragile without compensation. Another subset of hypotheses suggests that hypometric scaling arises from biotic interactions and correlated selection, with larger animals experiencing less selection for mass-specific growth or neurolocomotor performance. A additional third type of explanation comes from population genetics. Larger animals with their lower effective population sizes and subsequent less effective selection relative to drift may have more deleterious mutations, reducing maximal performance and metabolic rates. Resolving the evolutionary explanation for the hypometric scaling of metabolism and associated variables is a major challenge for organismal and evolutionary biology. To aid progress, we identify some variation in terminology use that has impeded cross-field conversations on scaling. We also suggest that promising directions for the field to move forward include: 1) studies examining the linkages between ontogenetic, population-level, and cross-species allometries, 2) studies linking scaling to ecological or phylogenetic context, 3) studies that consider multiple, possibly interacting hypotheses, and 4) obtaining better field data for metabolic rates and the life history correlates of metabolic rate such as lifespan, growth rate and reproduction.
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Affiliation(s)
- Jon F Harrison
- School of Life Sciences, Arizona State University, Tempe, AZ 85287-4501, USA
| | - Andrew Biewener
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
| | - Joanna R Bernhardt
- Department of Zoology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- Yale Institute for Biospheric Studies, New Haven, CT 06520, USA
| | - Joseph R Burger
- Department of Biology, University of Kentucky, Lexington, KY 40506, USA
| | - James H Brown
- Center for Evolutionary and Theoretical Immunology, The University of New Mexico, Albuquerque, NM 87131, USA
| | - Zach N Coto
- Department of Biology, Boston University, Boston, MA 02215, USA
| | - Meghan E Duell
- Department of Biology, The University of Western Ontario, London, ON N6A 3K7, Canada
| | - Michael Lynch
- Biodesign Center for Mechanisms of Evolution, Arizona State University, Tempe, AZ 85281, USA
| | - Emma R Moffett
- Department of Ecology and Evolution, University of California, Irvine, CA 92697, USA
| | - Tommy Norin
- DTU Aqua | National Institute of Aquatic Resources, Technical University of Denmark, Anker Engelunds Vej 1 Bygning 101A, 2800 Kgs. Lyngby, Denmark
| | - Amanda K Pettersen
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - Felisa A Smith
- Department of Biology, University of New Mexico, Albuquerque, NM 87131, USA
| | - Ummat Somjee
- Smithsonian Tropical Research Institute, Panama City, Panama
| | | | - Terrie M Williams
- Division of Physical and Biological Sciences, University of California, Santa Cruz, CA 95064, USA
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14
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Maher AE, Burin G, Cox PG, Maddox TW, Maidment SCR, Cooper N, Schachner ER, Bates KT. Body size, shape and ecology in tetrapods. Nat Commun 2022; 13:4340. [PMID: 35896591 PMCID: PMC9329317 DOI: 10.1038/s41467-022-32028-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 07/14/2022] [Indexed: 11/17/2022] Open
Abstract
Body size and shape play fundamental roles in organismal function and it is expected that animals may possess body proportions that are well-suited to their ecological niche. Tetrapods exhibit a diverse array of body shapes, but to date this diversity in body proportions and its relationship to ecology have not been systematically quantified. Using whole-body skeletal models of 410 extinct and extant tetrapods, we show that allometric relationships vary across individual body segments thereby yielding changes in overall body shape as size increases. However, we also find statistical support for quadratic relationships indicative of differential scaling in small-medium versus large animals. Comparisons of locomotor and dietary groups highlight key differences in body proportions that may mechanistically underlie occupation of major ecological niches. Our results emphasise the pivotal role of body proportions in the broad-scale ecological diversity of tetrapods. Here, the authors examine how body size, shape, and segment proportions correspond to ecology in models of 410 tetrapods. They find variable allometric relationships, differential scaling in small and large animals, and body proportions as a potential niche occupation mechanism.
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Affiliation(s)
- Alice E Maher
- Department of Musculoskeletal & Ageing Science, Institute of Life Course & Medical Sciences, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool, L7 8TX, UK.
| | - Gustavo Burin
- Natural History Museum, London, Cromwell Road, London, SW7 5BD, UK
| | - Philip G Cox
- Department of Archaeology and Hull York Medical School, University of York, PalaeoHub, Wentworth Way, Heslington, York, YO10 5DD, UK
| | - Thomas W Maddox
- School of Veterinary Science, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Small Animal Teaching Hospital, Leahurst Campus, Chester High Road, Neston, CH64 7TE, UK
| | - Susannah C R Maidment
- Department of Earth Sciences, Natural History Museum, London, Cromwell Road, London, SW7 5BD, UK
| | - Natalie Cooper
- Natural History Museum, London, Cromwell Road, London, SW7 5BD, UK
| | - Emma R Schachner
- Department of Cell Biology & Anatomy, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, LA, USA
| | - Karl T Bates
- Department of Musculoskeletal & Ageing Science, Institute of Life Course & Medical Sciences, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool, L7 8TX, UK
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15
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Cooke R, Gearty W, Chapman ASA, Dunic J, Edgar GJ, Lefcheck JS, Rilov G, McClain CR, Stuart-Smith RD, Kathleen Lyons S, Bates AE. Anthropogenic disruptions to longstanding patterns of trophic-size structure in vertebrates. Nat Ecol Evol 2022; 6:684-692. [PMID: 35449460 DOI: 10.1038/s41559-022-01726-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 03/07/2022] [Indexed: 11/09/2022]
Abstract
Diet and body mass are inextricably linked in vertebrates: while herbivores and carnivores have converged on much larger sizes, invertivores and omnivores are, on average, much smaller, leading to a roughly U-shaped relationship between body size and trophic guild. Although this U-shaped trophic-size structure is well documented in extant terrestrial mammals, whether this pattern manifests across diverse vertebrate clades and biomes is unknown. Moreover, emergence of the U-shape over geological time and future persistence are unknown. Here we compiled a comprehensive dataset of diet and body size spanning several vertebrate classes and show that the U-shaped pattern is taxonomically and biogeographically universal in modern vertebrate groups, except for marine mammals and seabirds. We further found that, for terrestrial mammals, this U-shape emerged by the Palaeocene and has thus persisted for at least 66 million years. Yet disruption of this fundamental trophic-size structure in mammals appears likely in the next century, based on projected extinctions. Actions to prevent declines in the largest animals will sustain the functioning of Earth's wild ecosystems and biomass energy distributions that have persisted through deep time.
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Affiliation(s)
- Rob Cooke
- UK Centre for Ecology & Hydrology, Wallingford, UK. .,Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden. .,Gothenburg Global Biodiversity Centre, Gothenburg, Sweden.
| | - William Gearty
- School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, NE, USA.
| | - Abbie S A Chapman
- Centre for Biodiversity and Environment Research, Department of Genetics, Evolution and Environment, University College London, London, UK
| | - Jillian Dunic
- Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Graham J Edgar
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
| | - Jonathan S Lefcheck
- Tennenbaum Marine Observatories Network and MarineGEO Program, Smithsonian Environmental Research Center, Edgewater, MD, USA
| | - Gil Rilov
- National Institute of Oceanography, Israel Limnological and Oceanographic Research, Haifa, Israel
| | | | - Rick D Stuart-Smith
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
| | - S Kathleen Lyons
- School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Amanda E Bates
- Biology Department, University of Victoria, Victoria, British Columbia, Canada
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16
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Rial RV, Canellas F, Akaârir M, Rubiño JA, Barceló P, Martín A, Gamundí A, Nicolau MC. The Birth of the Mammalian Sleep. BIOLOGY 2022; 11:biology11050734. [PMID: 35625462 PMCID: PMC9138988 DOI: 10.3390/biology11050734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 05/05/2022] [Indexed: 11/16/2022]
Abstract
Simple Summary Mammals evolved from reptiles as a consequence of an evolutionary bottleneck. Some diurnal reptiles extended their activity, first to twilight and then to the entire dark time. This forced the change of the visual system. Pursuing maximal sensitivity, they abandoned the filters protecting the eyes against the dangerous diurnal light, which, in turn, forced immobility in lightproof burrows during light time. This was the birth of the mammalian sleep. Then, the Cretacic-Paleogene extinction of dinosaurs leaved free the diurnal niche and allowed the expansion of a few early mammals to diurnal life and the high variability of sleep traits. On the other hand, we propose that the idling rest is a state showing homeostatic regulation. Therefore, the difference between behavioral rest and wakeful idling is rather low: both show quiescence, raised sensory thresholds, reversibility, specific sleeping-resting sites and body positions, it is a pleasing state, and both are dependent of circadian and homeostatic regulation. Indeed, the most important difference is the unconsciousness of sleep and the consciousness of wakeful idling. Thus, we propose that sleep is a mere upgrade of the wakeful rest, and both may have the same function: guaranteeing rest during a part of the daily cycle. Abstract Mammals evolved from small-sized reptiles that developed endothermic metabolism. This allowed filling the nocturnal niche. They traded-off visual acuity for sensitivity but became defenseless against the dangerous daylight. To avoid such danger, they rested with closed eyes in lightproof burrows during light-time. This was the birth of the mammalian sleep, the main finding of this report. Improved audition and olfaction counterweighed the visual impairments and facilitated the cortical development. This process is called “The Nocturnal Evolutionary Bottleneck”. Pre-mammals were nocturnal until the Cretacic-Paleogene extinction of dinosaurs. Some early mammals returned to diurnal activity, and this allowed the high variability in sleeping patterns observed today. The traits of Waking Idleness are almost identical to those of behavioral sleep, including homeostatic regulation. This is another important finding of this report. In summary, behavioral sleep seems to be an upgrade of Waking Idleness Indeed, the trait that never fails to show is quiescence. We conclude that the main function of sleep consists in guaranteeing it during a part of the daily cycle.
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Affiliation(s)
- Rubén V. Rial
- Laboratori de Neurofisiologia del Son i dels Ritmes Biològics, Grup de Recerca Neurofisiologia del Son i Ritmes Biològics, Department of Biologia, Universitat de les Illes Balears, Ctra Valldemossa, km 7.5, 07122 Palma de Mallorca, Illes Balears, Spain; (F.C.); (M.A.); (J.A.R.); (P.B.); (A.M.); (A.G.); (M.C.N.)
- IdISBa, Institut d’Investigació Sanitària de les Illes Balears, Hospital Son Espases, 07120 Palma de Mallorca, Illes Balears, Spain
- IUNICS, Institut Universitari d’Investigació en Ciències de la Salut, Hospital Universitary Son Espases, 07120 Palma de Mallorca, Illes Balears, Spain
- Correspondence: ; Tel.: +34-971-173-147; Fax: +34-971-173-184
| | - Francesca Canellas
- Laboratori de Neurofisiologia del Son i dels Ritmes Biològics, Grup de Recerca Neurofisiologia del Son i Ritmes Biològics, Department of Biologia, Universitat de les Illes Balears, Ctra Valldemossa, km 7.5, 07122 Palma de Mallorca, Illes Balears, Spain; (F.C.); (M.A.); (J.A.R.); (P.B.); (A.M.); (A.G.); (M.C.N.)
- IdISBa, Institut d’Investigació Sanitària de les Illes Balears, Hospital Son Espases, 07120 Palma de Mallorca, Illes Balears, Spain
- IUNICS, Institut Universitari d’Investigació en Ciències de la Salut, Hospital Universitary Son Espases, 07120 Palma de Mallorca, Illes Balears, Spain
| | - Mourad Akaârir
- Laboratori de Neurofisiologia del Son i dels Ritmes Biològics, Grup de Recerca Neurofisiologia del Son i Ritmes Biològics, Department of Biologia, Universitat de les Illes Balears, Ctra Valldemossa, km 7.5, 07122 Palma de Mallorca, Illes Balears, Spain; (F.C.); (M.A.); (J.A.R.); (P.B.); (A.M.); (A.G.); (M.C.N.)
- IdISBa, Institut d’Investigació Sanitària de les Illes Balears, Hospital Son Espases, 07120 Palma de Mallorca, Illes Balears, Spain
- IUNICS, Institut Universitari d’Investigació en Ciències de la Salut, Hospital Universitary Son Espases, 07120 Palma de Mallorca, Illes Balears, Spain
| | - José A. Rubiño
- Laboratori de Neurofisiologia del Son i dels Ritmes Biològics, Grup de Recerca Neurofisiologia del Son i Ritmes Biològics, Department of Biologia, Universitat de les Illes Balears, Ctra Valldemossa, km 7.5, 07122 Palma de Mallorca, Illes Balears, Spain; (F.C.); (M.A.); (J.A.R.); (P.B.); (A.M.); (A.G.); (M.C.N.)
- IdISBa, Institut d’Investigació Sanitària de les Illes Balears, Hospital Son Espases, 07120 Palma de Mallorca, Illes Balears, Spain
- IUNICS, Institut Universitari d’Investigació en Ciències de la Salut, Hospital Universitary Son Espases, 07120 Palma de Mallorca, Illes Balears, Spain
| | - Pere Barceló
- Laboratori de Neurofisiologia del Son i dels Ritmes Biològics, Grup de Recerca Neurofisiologia del Son i Ritmes Biològics, Department of Biologia, Universitat de les Illes Balears, Ctra Valldemossa, km 7.5, 07122 Palma de Mallorca, Illes Balears, Spain; (F.C.); (M.A.); (J.A.R.); (P.B.); (A.M.); (A.G.); (M.C.N.)
- IdISBa, Institut d’Investigació Sanitària de les Illes Balears, Hospital Son Espases, 07120 Palma de Mallorca, Illes Balears, Spain
- IUNICS, Institut Universitari d’Investigació en Ciències de la Salut, Hospital Universitary Son Espases, 07120 Palma de Mallorca, Illes Balears, Spain
| | - Aida Martín
- Laboratori de Neurofisiologia del Son i dels Ritmes Biològics, Grup de Recerca Neurofisiologia del Son i Ritmes Biològics, Department of Biologia, Universitat de les Illes Balears, Ctra Valldemossa, km 7.5, 07122 Palma de Mallorca, Illes Balears, Spain; (F.C.); (M.A.); (J.A.R.); (P.B.); (A.M.); (A.G.); (M.C.N.)
- IdISBa, Institut d’Investigació Sanitària de les Illes Balears, Hospital Son Espases, 07120 Palma de Mallorca, Illes Balears, Spain
- IUNICS, Institut Universitari d’Investigació en Ciències de la Salut, Hospital Universitary Son Espases, 07120 Palma de Mallorca, Illes Balears, Spain
| | - Antoni Gamundí
- Laboratori de Neurofisiologia del Son i dels Ritmes Biològics, Grup de Recerca Neurofisiologia del Son i Ritmes Biològics, Department of Biologia, Universitat de les Illes Balears, Ctra Valldemossa, km 7.5, 07122 Palma de Mallorca, Illes Balears, Spain; (F.C.); (M.A.); (J.A.R.); (P.B.); (A.M.); (A.G.); (M.C.N.)
- IdISBa, Institut d’Investigació Sanitària de les Illes Balears, Hospital Son Espases, 07120 Palma de Mallorca, Illes Balears, Spain
- IUNICS, Institut Universitari d’Investigació en Ciències de la Salut, Hospital Universitary Son Espases, 07120 Palma de Mallorca, Illes Balears, Spain
| | - M. Cristina Nicolau
- Laboratori de Neurofisiologia del Son i dels Ritmes Biològics, Grup de Recerca Neurofisiologia del Son i Ritmes Biològics, Department of Biologia, Universitat de les Illes Balears, Ctra Valldemossa, km 7.5, 07122 Palma de Mallorca, Illes Balears, Spain; (F.C.); (M.A.); (J.A.R.); (P.B.); (A.M.); (A.G.); (M.C.N.)
- IdISBa, Institut d’Investigació Sanitària de les Illes Balears, Hospital Son Espases, 07120 Palma de Mallorca, Illes Balears, Spain
- IUNICS, Institut Universitari d’Investigació en Ciències de la Salut, Hospital Universitary Son Espases, 07120 Palma de Mallorca, Illes Balears, Spain
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17
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Onstein RE, Kissling WD, Linder HP. The megaherbivore gap after the non-avian dinosaur extinctions modified trait evolution and diversification of tropical palms. Proc Biol Sci 2022; 289:20212633. [PMID: 35414237 PMCID: PMC9006001 DOI: 10.1098/rspb.2021.2633] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The Cretaceous-Palaeogene (K-Pg) extinction of the non-avian dinosaurs (66 Ma) led to a 25 million year gap of megaherbivores (>1000 kg) before the evolution of megaherbivorous mammals in the Late Eocene (40 Ma). The botanical consequences of this 'Palaeocene megaherbivore gap' (PMHG) remain poorly explored. We hypothesize that the absence of megaherbivores should result in changes in the diversification and trait evolution of associated plant lineages. We used phylogenetic time- and trait-dependent diversification models with palms (Arecaceae) and show that the PMHG was characterized by speciation slowdowns, decreased evolution of armature and increased evolution of megafaunal (≥4 cm) fruits. This suggests that the absence of browsing by megaherbivores during the PMHG may have led to a loss of defence traits, but the absence of megaherbivorous seed dispersers did not lead to a loss of megafaunal fruits. Instead, increases in PMHG fruit sizes may be explained by simultaneously rising temperatures, rainforest expansion, and the subsequent radiation of seed-dispersing birds and mammals. We show that the profound impact of the PMHG on plant diversification can be detected even with the overwriting of adaptations by the subsequent Late Eocene opening up of megaherbivore-associated ecological opportunities. Our study provides a quantitative, comparative framework to assess diversification and adaptation during one of the most enigmatic periods in angiosperm history.
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Affiliation(s)
- Renske E. Onstein
- Evolution and Adaptation, German Centre for Integrative Biodiversity Research (iDiv) Halle–Jena–Leipzig, Leipzig 04103 Germany
| | - W. Daniel Kissling
- Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam, Amsterdam, Noord-Holland, The Netherlands
| | - H. Peter Linder
- Department of Systematic and Evolutionary Botany, University of Zurich, Zurich, ZH Switzerland
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18
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Bertrand OC, Shelley SL, Williamson TE, Wible JR, Chester SGB, Flynn JJ, Holbrook LT, Lyson TR, Meng J, Miller IM, Püschel HP, Smith T, Spaulding M, Tseng ZJ, Brusatte SL. Brawn before brains in placental mammals after the end-Cretaceous extinction. Science 2022; 376:80-85. [PMID: 35357913 DOI: 10.1126/science.abl5584] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Mammals are the most encephalized vertebrates, with the largest brains relative to body size. Placental mammals have particularly enlarged brains, with expanded neocortices for sensory integration, the origins of which are unclear. We used computed tomography scans of newly discovered Paleocene fossils to show that contrary to the convention that mammal brains have steadily enlarged over time, early placentals initially decreased their relative brain sizes because body mass increased at a faster rate. Later in the Eocene, multiple crown lineages independently acquired highly encephalized brains through marked growth in sensory regions. We argue that the placental radiation initially emphasized increases in body size as extinction survivors filled vacant niches. Brains eventually became larger as ecosystems saturated and competition intensified.
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Affiliation(s)
- Ornella C Bertrand
- School of GeoSciences, University of Edinburgh, Grant Institute, Edinburgh, Scotland EH9 3FE, UK
| | - Sarah L Shelley
- School of GeoSciences, University of Edinburgh, Grant Institute, Edinburgh, Scotland EH9 3FE, UK.,Section of Mammals, Carnegie Museum of Natural History, Pittsburgh, PA, USA
| | | | - John R Wible
- Section of Mammals, Carnegie Museum of Natural History, Pittsburgh, PA, USA
| | - Stephen G B Chester
- Department of Anthropology, Brooklyn College, City University of New York, Brooklyn, NY, USA.,Department of Anthropology, The Graduate Center, City University of New York, New York, NY, USA.,New York Consortium in Evolutionary Primatology, New York, NY, USA
| | - John J Flynn
- Division of Paleontology, American Museum of Natural History, New York, NY, USA.,Department of Earth and Environmental Sciences, Columbia University, New York, NY, USA.,Ecology, Evolutionary Biology, and Behavior subprogram, PhD Program in Biology, The Graduate Center, City University of New York, New York, NY, USA.,PhD Program in Earth and Environmental Sciences, The Graduate Center, City University of New York, New York, NY, USA
| | - Luke T Holbrook
- Department of Biological Sciences, Rowan University, Glassboro, NJ, USA
| | | | - Jin Meng
- Division of Paleontology, American Museum of Natural History, New York, NY, USA
| | - Ian M Miller
- Denver Museum of Nature & Science, Denver, CO, USA.,National Geographic Society, Washington, DC, USA
| | - Hans P Püschel
- School of GeoSciences, University of Edinburgh, Grant Institute, Edinburgh, Scotland EH9 3FE, UK
| | - Thierry Smith
- Directorate Earth and History of Life, Royal Belgian Institute of Natural Sciences, Brussels, Belgium
| | - Michelle Spaulding
- Department of Biological Sciences, Purdue University Northwest, Westville, IN, USA
| | - Z Jack Tseng
- Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, CA, USA
| | - Stephen L Brusatte
- School of GeoSciences, University of Edinburgh, Grant Institute, Edinburgh, Scotland EH9 3FE, UK.,New Mexico Museum of Natural History and Science, Albuquerque, NM, USA
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19
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Smith FA. The road to a larger brain. Science 2022; 376:27-28. [PMID: 35357943 DOI: 10.1126/science.abo1985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Ecological opportunities in the early Cenozoic favored larger, not smarter, mammals.
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Affiliation(s)
- Felisa A Smith
- Department of Biology, University of New Mexico, Albuquerque, NM 87131-0001, USA
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20
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Christison BE, Gaidies F, Pineda-Munoz S, Evans AR, Gilbert MA, Fraser D. Dietary niches of creodonts and carnivorans of the late Eocene Cypress Hills Formation. J Mammal 2022; 103:2-17. [PMID: 35087328 PMCID: PMC8789764 DOI: 10.1093/jmammal/gyab123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 10/09/2021] [Indexed: 11/14/2022] Open
Abstract
Modern North American carnivorous mammal assemblages consist of species from a single clade: the Carnivora. Carnivorans once coexisted with members of other meat-eating clades, including the creodonts (Hyaenodontida and Oxyaenida). Creodonts, however, went extinct in North America during the late Eocene and early Oligocene, potentially due to niche overlap and resource competition with contemporary carnivorans. In this study, we employ a community ecology approach to understand whether the dietary niches of coexisting creodonts and carnivorans overlapped during the late Eocene (Chadronian North American Land Mammal Age), a time when creodonts were dwindling and carnivorans were diversifying. We quantify niche overlap based on inferences of diet from carnassial tooth shape estimated using Orientation Patch Count, Dirichlet's Normal Surface Energy, and linear dental measurements as well as from body mass for all species in the Calf Creek Local Fauna of Cypress Hills, Saskatchewan (Treaty 4 land). Although creodonts and carnivorans shared characteristics of their carnassial tooth shape, suggesting similar chewing mechanics and feeding habits, we find that marked differences in body size likely facilitated niche partitioning, at least between the largest creodonts and carnivorans. Calculations of prey focus masses and prey mass spectra indicate that only the smallest creodont may have experienced significant competition for prey with the coeval carnivorans. We suggest that the ultimate extinction of creodonts from North America during the late Eocene and Oligocene was unlikely to have been driven by factors related to niche overlap with carnivorans.
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Affiliation(s)
| | - Fred Gaidies
- Department of Earth Sciences, Carleton University, Ottawa, Ontario, Canada
| | - Silvia Pineda-Munoz
- Department of Earth and Atmospheric Sciences, Indiana University, Bloomington, IN, USA
- Department of Paleobiology, Smithsonian National Museum of Natural History, Washington, District of Columbia, USA
| | - Alistair R Evans
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
- Geosciences, Museums Victoria, Melbourne, Victoria, Australia
| | - Marisa A Gilbert
- Palaeobiology, Canadian Museum of Nature, Ottawa, Ontario, Canada
| | - Danielle Fraser
- Department of Biology, Carleton University, Ottawa, Ontario, Canada
- Department of Earth Sciences, Carleton University, Ottawa, Ontario, Canada
- Department of Paleobiology, Smithsonian National Museum of Natural History, Washington, District of Columbia, USA
- Palaeobiology, Canadian Museum of Nature, Ottawa, Ontario, Canada
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21
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Abraham JO, Hempson GP, Faith JT, Staver AC. Seasonal strategies differ between tropical and extratropical herbivores. J Anim Ecol 2021; 91:681-692. [PMID: 34921402 DOI: 10.1111/1365-2656.13651] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 12/12/2021] [Indexed: 11/29/2022]
Abstract
Seasonal diet shifts and migration are key components of large herbivore population dynamics, but we lack a systematic understanding of how these behaviors are distributed on a macroecological scale. The prevalence of seasonal strategies is likely related to herbivore body size and feeding guild, and may also be influenced by properties of the environment, such as soil nutrient availability and climate seasonality. We evaluated the distribution of seasonal dietary shifts and migration across large-bodied mammalian herbivores and determined how these behaviors related to diet, body size, and environment. We found that herbivore strategies were consistently correlated with their traits: seasonal diet shifts were most prevalent among mixed feeding herbivores and migration among grazers and larger herbivores. Seasonality also played a role, particularly for migration, which was more common at higher latitudes. Both dietary shifts and migration were more widespread among extratropical herbivores, which also exhibited more intermediate diets and body sizes. Our findings suggest that strong seasonality in extratropical systems imposes pressure on herbivores, necessitating widespread behavioral responses to navigate seasonal resource bottlenecks. It follows that tropical and extratropical herbivores may have divergent responses to global change, with intensifying herbivore pressure in extratropical systems contrasting with diminishing herbivore pressure in tropical systems.
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Affiliation(s)
- Joel O Abraham
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA
| | - Gareth P Hempson
- Centre for African Ecology, School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Wits, 2050, South Africa
| | - J Tyler Faith
- Natural History Museum of Utah, University of Utah, Salt Lake City, UT, USA.,Department of Anthropology, University of Utah, Salt Lake City, UT, USA.,Origins Centre, University of the Witwatersrand, Braamfontein, 2000, Johannesburg, South Africa
| | - A Carla Staver
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA
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22
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Hughes JJ, Berv JS, Chester SGB, Sargis EJ, Field DJ. Ecological selectivity and the evolution of mammalian substrate preference across the K-Pg boundary. Ecol Evol 2021; 11:14540-14554. [PMID: 34765124 PMCID: PMC8571592 DOI: 10.1002/ece3.8114] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 08/16/2021] [Accepted: 08/24/2021] [Indexed: 11/21/2022] Open
Abstract
The Cretaceous-Paleogene (K-Pg) mass extinction 66 million years ago was characterized by a worldwide ecological catastrophe and rapid species turnover. Large-scale devastation of forested environments resulting from the Chicxulub asteroid impact likely influenced the evolutionary trajectories of multiple clades in terrestrial environments, and it has been hypothesized to have biased survivorship in favour of nonarboreal lineages across the K-Pg boundary. Here, we evaluate patterns of substrate preferences across the K-Pg boundary among crown group mammals, a group that underwent rapid diversification following the mass extinction. Using Bayesian, likelihood, and parsimony reconstructions, we identify patterns of mammalian ecological selectivity that are broadly similar to those previously hypothesized for birds. Models based on extant taxa indicate predominant K-Pg survivorship among semi- or nonarboreal taxa, followed by numerous independent transitions to arboreality in the early Cenozoic. However, contrary to the predominant signal, some or all members of total-clade Euarchonta (Primates + Dermoptera + Scandentia) appear to have maintained arboreal habits across the K-Pg boundary, suggesting ecological flexibility during an interval of global habitat instability. We further observe a pronounced shift in character state transitions away from plesiomorphic arboreality associated with the K-Pg transition. Our findings are consistent with the hypothesis that predominantly nonarboreal taxa preferentially survived the end-Cretaceous mass extinction, and emphasize the pivotal influence of the K-Pg transition in shaping the early evolutionary trajectories of extant terrestrial vertebrates.
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Affiliation(s)
- Jonathan J. Hughes
- Department of Ecology & Evolutionary BiologyCornell UniversityIthacaNew YorkUSA
| | - Jacob S. Berv
- Department of Ecology & Evolutionary BiologyCornell UniversityIthacaNew YorkUSA
- Department of Ecology & Evolutionary BiologyUniversity of MichiganAnn ArborMichiganUSA
- University of Michigan Museum of PaleontologyUniversity of MichiganAnn ArborMichiganUSA
| | - Stephen G. B. Chester
- Department of AnthropologyBrooklyn CollegeCity University of New YorkBrooklynNew YorkUSA
- Department of AnthropologyThe Graduate CenterCity University of New YorkNew YorkNew YorkUSA
- New York Consortium in Evolutionary PrimatologyNew YorkNew YorkUSA
| | - Eric J. Sargis
- Department of AnthropologyYale UniversityNew HavenConnecticutUSA
- Divisions of Vertebrate Paleontology and Vertebrate ZoologyYale Peabody Museum of Natural HistoryNew HavenConnecticutUSA
- Yale Institute for Biospheric StudiesNew HavenConnecticutUSA
| | - Daniel J. Field
- Department of Earth SciencesUniversity of CambridgeCambridgeUK
- Museum of ZoologyUniversity of CambridgeCambridgeUK
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23
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Convergent evolution of a genomic rearrangement may explain cancer resistance in hystrico- and sciuromorpha rodents. NPJ Aging Mech Dis 2021; 7:20. [PMID: 34471123 PMCID: PMC8410860 DOI: 10.1038/s41514-021-00072-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 06/21/2021] [Indexed: 11/09/2022] Open
Abstract
The rodents of hystricomorpha and sciuromorpha suborders exhibit remarkably lower incidence of cancer. The underlying genetic basis remains obscure. We report a convergent evolutionary split of human 3p21.31, a locus hosting a large number of tumour-suppressor genes (TSGs) and frequently deleted in several tumour types, in hystrico- and sciuromorphs. Analysis of 34 vertebrate genomes revealed that the synteny of 3p21.31 cluster is functionally and evolutionarily constrained in most placental mammals, but exhibit large genomic interruptions independently in hystricomorphs and sciuromorphs, owing to relaxation of underlying constraints. Hystrico- and sciuromorphs, therefore, escape from pro-tumorigenic co-deletion of several TSGs in cis. The split 3p21.31 sub-clusters gained proximity to proto-oncogene clusters from elsewhere, which might further nullify pro-tumorigenic impact of copy number variations due to co-deletion or co-amplification of genes with opposing effects. The split of 3p21.31 locus coincided with the accelerated rate of its gene expression and the body mass evolution of ancestral hystrico- and sciuromorphs. The genes near breakpoints were associated with the traits specific to hystrico- and sciuromorphs, implying adaptive significance. We conclude that the convergently evolved chromosomal interruptions of evolutionarily constrained 3p21.31 cluster might have impacted evolution of cancer resistance, body mass variation and ecological adaptations in hystrico- and sciuromorphs.
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24
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Brocklehurst N, Panciroli E, Benevento GL, Benson RBJ. Mammaliaform extinctions as a driver of the morphological radiation of Cenozoic mammals. Curr Biol 2021; 31:2955-2963.e4. [PMID: 34004143 DOI: 10.1016/j.cub.2021.04.044] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 12/04/2020] [Accepted: 04/19/2021] [Indexed: 11/17/2022]
Abstract
Adaptive radiations are hypothesized as a generating mechanism for much of the morphological diversity of extant species.1-7 The Cenozoic radiation of placental mammals, the foundational example of this concept,8,9 gave rise to much of the morphological disparity of extant mammals, and is generally attributed to relaxed evolutionary constraints following the extinction of non-avian dinosaurs.10-13 However, study of this and other radiations has focused on variation in evolutionary rates,4,5,7,14 leaving the extent to which relaxation of constraints enabled the origin of novel phenotypes less well characterized.15-17 We evaluate constraints on morphological evolution among mammaliaforms (mammals and their closest relatives) using a new method that quantifies the capacity of evolutionary change to generate phenotypic novelty. We find that Mesozoic crown-group therians, which include the ancestors of placental mammals, were significantly more constrained than other mammaliaforms. Relaxation of these constraints occurred in the mid-Paleocene, post-dating the extinction of non-avian dinosaurs at the K/Pg boundary, instead coinciding with important environmental shifts and with declining ecomorphological diversity in non-theriimorph mammaliaforms. This relaxation occurred even in small-bodied Cenozoic mammals weighing <100 g, which are unlikely to have competed with dinosaurs. Instead, our findings support a more complex model whereby Mesozoic crown therian evolution was in part constrained by co-occurrence with disparate mammaliaforms, as well as by the presence of dinosaurs, within-lineage incumbency effects, and environmental factors. Our results demonstrate that variation in evolutionary constraints can occur independently of variation in evolutionary rate, and that both make important contributions to the understanding of adaptive radiations.
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Affiliation(s)
- Neil Brocklehurst
- Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK.
| | - Elsa Panciroli
- Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK; Oxford University Museum of Natural History, Parks Road, Oxford OX1 3PW, UK
| | - Gemma Louise Benevento
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Roger B J Benson
- Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK
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25
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Schroeder K, Lyons SK, Smith FA. The influence of juvenile dinosaurs on community structure and diversity. Science 2021; 371:941-944. [PMID: 33632845 DOI: 10.1126/science.abd9220] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 01/21/2021] [Indexed: 12/15/2022]
Abstract
Despite dominating biodiversity in the Mesozoic, dinosaurs were not speciose. Oviparity constrained even gigantic dinosaurs to less than 15 kg at birth; growth through multiple morphologies led to the consumption of different resources at each stage. Such disparity between neonates and adults could have influenced the structure and diversity of dinosaur communities. Here, we quantified this effect for 43 communities across 136 million years and seven continents. We found that megatheropods (more than 1000 kg) such as tyrannosaurs had specific effects on dinosaur community structure. Although herbivores spanned the body size range, communities with megatheropods lacked carnivores weighing 100 to 1000 kg. We demonstrate that juvenile megatheropods likely filled the mesocarnivore niche, resulting in reduced overall taxonomic diversity. The consistency of this pattern suggests that ontogenetic niche shift was an important factor in generating dinosaur community structure and diversity.
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Affiliation(s)
- Katlin Schroeder
- Department of Biology, University of New Mexico, Albuquerque, NM 87131, USA.
| | - S Kathleen Lyons
- School of Biological Sciences, University of Nebraska, Lincoln, NE 68588, USA
| | - Felisa A Smith
- Department of Biology, University of New Mexico, Albuquerque, NM 87131, USA
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26
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Mahmood T, Vu TT, Campos-Arceiz A, Akrim F, Andleeb S, Farooq M, Hamid A, Munawar N, Waseem M, Hussain A, Fatima H, Khan MR, Mahmood S. Historical and current distribution ranges and loss of mega-herbivores and carnivores of Asia. PeerJ 2021; 9:e10738. [PMID: 33628635 PMCID: PMC7894109 DOI: 10.7717/peerj.10738] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 12/18/2020] [Indexed: 11/20/2022] Open
Abstract
Ecosystem functioning is dependent a lot on large mammals, which are, however, vulnerable and facing extinction risks due to human impacts mainly. Megafauna of Asia has been declining for a long, not only in numbers but also in their distribution ranges. In the current study, we collected information on past and current occurrence and distribution records of Asia’s megafauna species. We reconstructed the historical distribution ranges of the six herbivores and four carnivores for comparison with their present ranges, to quantify spatially explicit levels of mega-defaunation. Results revealed that historically the selected megafauna species were more widely distributed than at current. Severe range contraction was observed for the Asiatic lion, three rhino species, Asian elephant, tigers, and tapirs. Defaunation maps generated have revealed the vanishing of megafauna from parts of the East, Southeast, and Southwest Asia, even some protected Areas losing up to eight out of ten megafaunal species. These defaunation maps can help develop future conservation policies, to save the remaining distribution ranges of large mammals.
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Affiliation(s)
- Tariq Mahmood
- Department of Wildlife Management, PMAS-Arid Agriculture University Rawalpindi, Rawalpindi, Punjab, Pakistan.,School of Geography, University of Nottingham Malaysia Campus, Semenyih, Selangor, Malaysia
| | - Tuong Thuy Vu
- School of Geography, University of Nottingham Malaysia Campus, Semenyih, Selangor, Malaysia.,Faculty of Engineering and Science, Curtin University Malaysia, Miri, Sarawak, Malaysia
| | - Ahimsa Campos-Arceiz
- School of Geography, University of Nottingham Malaysia Campus, Semenyih, Selangor, Malaysia.,Southeast Asia Biodiversity Research Institute, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Xishuangbanna, China
| | - Faraz Akrim
- Department of Wildlife Management, PMAS-Arid Agriculture University Rawalpindi, Rawalpindi, Punjab, Pakistan.,Department of Zoology, University of Kotli, Azad Jammu and Kashmir, Pakistan
| | - Shaista Andleeb
- School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan, Hubei Province, China
| | - Muhammad Farooq
- Department of Wildlife Management, PMAS-Arid Agriculture University Rawalpindi, Rawalpindi, Punjab, Pakistan
| | - Abdul Hamid
- Department of Wildlife Management, PMAS-Arid Agriculture University Rawalpindi, Rawalpindi, Punjab, Pakistan
| | - Nadeem Munawar
- Department of Wildlife Management, PMAS-Arid Agriculture University Rawalpindi, Rawalpindi, Punjab, Pakistan
| | - Muhammad Waseem
- Department of Wildlife Management, PMAS-Arid Agriculture University Rawalpindi, Rawalpindi, Punjab, Pakistan
| | - Abid Hussain
- Department of Wildlife Management, PMAS-Arid Agriculture University Rawalpindi, Rawalpindi, Punjab, Pakistan
| | - Hira Fatima
- Department of Wildlife Management, PMAS-Arid Agriculture University Rawalpindi, Rawalpindi, Punjab, Pakistan
| | - Muhammad Raza Khan
- Department of Wildlife Management, PMAS-Arid Agriculture University Rawalpindi, Rawalpindi, Punjab, Pakistan
| | - Sajid Mahmood
- Department of Zoology, Hazara University, Mansehra, Khyber Pakhtunkhwa, Pakistan
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27
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Kim SL, Zeichner SS, Colman AS, Scher HD, Kriwet J, Mörs T, Huber M. Probing the Ecology and Climate of the Eocene Southern Ocean With Sand Tiger Sharks Striatolamia macrota. PALEOCEANOGRAPHY AND PALEOCLIMATOLOGY 2020; 35:e2020PA003997. [PMID: 34222817 PMCID: PMC8246854 DOI: 10.1029/2020pa003997] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 10/20/2020] [Accepted: 11/01/2020] [Indexed: 06/13/2023]
Abstract
Many explanations for Eocene climate change focus on the Southern Ocean-where tectonics influenced oceanic gateways, ocean circulation reduced heat transport, and greenhouse gas declines prompted glaciation. To date, few studies focus on marine vertebrates at high latitudes to discern paleoecological and paleoenvironmental impacts of this climate transition. The Tertiary Eocene La Meseta (TELM) Formation has a rich fossil assemblage to characterize these impacts; Striatolamia macrota, an extinct (†) sand tiger shark, is abundant throughout the La Meseta Formation. Body size is often tracked to characterize and integrate across multiple ecological dimensions. †S. macrota body size distributions indicate limited changes during TELMs 2-5 based on anterior tooth crown height (n = 450, mean = 19.6 ± 6.4 mm). Similarly, environmental conditions remained stable through this period based on δ18OPO4 values from tooth enameloid (n = 42; 21.5 ± 1.6‰), which corresponds to a mean temperature of 22.0 ± 4.0°C. Our preliminary ε Nd (n = 4) results indicate an early Drake Passage opening with Pacific inputs during TELM 2-3 (45-43 Ma) based on single unit variation with an overall radiogenic trend. Two possible hypotheses to explain these observations are (1) †S. macrota modified its migration behavior to ameliorate environmental changes related to the Drake Passage opening, or (2) the local climate change was small and gateway opening had little impact. While we cannot rule out an ecological explanation, a comparison with climate model results suggests that increased CO2 produces warm conditions that also parsimoniously explain the observations.
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Affiliation(s)
- Sora L. Kim
- Department of Geophysical SciencesUniversity of ChicagoChicagoILUSA
- Department of Life and Environmental SciencesUniversity of CaliforniaMercedCAUSA
| | - Sarah S. Zeichner
- Department of Geophysical SciencesUniversity of ChicagoChicagoILUSA
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCAUSA
| | - Albert S. Colman
- Department of Geophysical SciencesUniversity of ChicagoChicagoILUSA
- Department of Earth, Environment, and Planetary SciencesRice UniversityHoustonTXUSA
| | - Howie D. Scher
- Department of Earth, Ocean, and EnvironmentUniversity of South CarolinaColumbiaSCUSA
| | - Jürgen Kriwet
- Department of PalaeontologyUniversity of ViennaViennaAustria
| | - Thomas Mörs
- Department of PalaeobiologySwedish Museum of Natural HistoryStockholmSweden
- Bolin Centre for Climate ResearchStockholm UniversityStockholmSweden
| | - Matthew Huber
- Department of Earth, Atmosphere, and Planetary SciencesPurdue UniversityWest LafayetteINUSA
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28
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Bellot S, Bayton RP, Couvreur TLP, Dodsworth S, Eiserhardt WL, Guignard MS, Pritchard HW, Roberts L, Toorop PE, Baker WJ. On the origin of giant seeds: the macroevolution of the double coconut (Lodoicea maldivica) and its relatives (Borasseae, Arecaceae). THE NEW PHYTOLOGIST 2020; 228:1134-1148. [PMID: 32544251 PMCID: PMC7590125 DOI: 10.1111/nph.16750] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 05/29/2020] [Indexed: 05/25/2023]
Abstract
Seed size shapes plant evolution and ecosystems, and may be driven by plant size and architecture, dispersers, habitat and insularity. How these factors influence the evolution of giant seeds is unclear, as are the rate of evolution and the biogeographical consequences of giant seeds. We generated DNA and seed size data for the palm tribe Borasseae (Arecaceae) and its relatives, which show a wide diversity in seed size and include the double coconut (Lodoicea maldivica), the largest seed in the world. We inferred their phylogeny, dispersal history and rates of change in seed size, and evaluated the possible influence of plant size, inflorescence branching, habitat and insularity on these changes. Large seeds were involved in 10 oceanic dispersals. Following theoretical predictions, we found that: taller plants with fewer-branched inflorescences produced larger seeds; seed size tended to evolve faster on islands (except Madagascar); and seeds of shade-loving Borasseae tended to be larger. Plant size and inflorescence branching may constrain seed size in Borasseae and their relatives. The possible roles of insularity, habitat and dispersers are difficult to disentangle. Evolutionary contingencies better explain the gigantism of the double coconut than unusually high rates of seed size increase.
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Affiliation(s)
| | - Ross P. Bayton
- Royal Botanic Gardens, KewRichmond, SurreyTW9 3AEUK
- Department of Biological SciencesUniversity of ReadingWhiteknightsPO Box 217Reading, BerkshireRG6 6AHUK
| | | | - Steven Dodsworth
- Royal Botanic Gardens, KewRichmond, SurreyTW9 3AEUK
- School of Life SciencesUniversity of BedfordshireLutonLU1 3JUUK
| | - Wolf L. Eiserhardt
- Royal Botanic Gardens, KewRichmond, SurreyTW9 3AEUK
- Department of BiologyAarhus UniversityNy Munkegade 116Aarhus C8000Denmark
| | | | - Hugh W. Pritchard
- Royal Botanic Gardens, KewWakehurst Place, Wellcome Trust Millennium BuildingArdinglyWest SussexRH17 6TNUK
| | - Lucy Roberts
- Department of ZoologyUniversity of CambridgeDowning StreetCambridgeCB2 3EJUK
| | - Peter E. Toorop
- Royal Botanic Gardens, KewWakehurst Place, Wellcome Trust Millennium BuildingArdinglyWest SussexRH17 6TNUK
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29
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Le Verger K, Hautier L, Bardin J, Gerber S, Delsuc F, Billet G. Ontogenetic and static allometry in the skull and cranial units of nine-banded armadillos (Cingulata: Dasypodidae: Dasypus novemcinctus). Biol J Linn Soc Lond 2020. [DOI: 10.1093/biolinnean/blaa083] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Abstract
A large part of extant and past mammalian morphological diversity is related to variation in size through allometric effects. Previous studies suggested that craniofacial allometry is the dominant pattern underlying mammalian skull shape variation, but cranial allometries were rarely characterized within cranial units such as individual bones. Here, we used 3D geometric morphometric methods to study allometric patterns of the whole skull (global) and of cranial units (local) in a postnatal developmental series of nine-banded armadillos (Dasypus novemcinctus ssp.). Analyses were conducted at the ontogenetic and static levels, and for successive developmental stages. Our results support craniofacial allometry as the global pattern along with more local allometric trends, such as the relative posterior elongation of the infraorbital canal, the tooth row reduction on the maxillary, and the marked development of nuchal crests on the supraoccipital with increasing skull size. Our study also reports allometric proportions of shape variation varying substantially among cranial units and across ontogenetic stages. The multi-scale approach advocated here allowed unveiling previously unnoticed allometric variations, indicating an untapped complexity of cranial allometric patterns to further explain mammalian morphological evolution.
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Affiliation(s)
- Kévin Le Verger
- Museum national d’Histoire naturelle, Centre de Recherche en Paléontologie – Paris, UMR 7207 CR2P MNHN/CNRS/UPMC, Sorbonne Universités, Paris, France
| | - Lionel Hautier
- Institut des Sciences de l’Evolution, Université de Montpellier, UMR 5554 ISEM CNRS/IRD/EPHE, Montpellier cedex, France
- Natural History Museum of London, Department of Life Sciences, Mammal Section, London, UK
| | - Jérémie Bardin
- Museum national d’Histoire naturelle, Centre de Recherche en Paléontologie – Paris, UMR 7207 CR2P MNHN/CNRS/UPMC, Sorbonne Universités, Paris, France
| | - Sylvain Gerber
- Muséum national d’Histoire naturelle, Institut de Systématique, Évolution, Biodiversité, UMR 7205 ISYEB MNHN/CNRS/UPMC/EPHE, Sorbonne Universités, Paris, France
| | - Frédéric Delsuc
- Institut des Sciences de l’Evolution, Université de Montpellier, UMR 5554 ISEM CNRS/IRD/EPHE, Montpellier cedex, France
| | - Guillaume Billet
- Museum national d’Histoire naturelle, Centre de Recherche en Paléontologie – Paris, UMR 7207 CR2P MNHN/CNRS/UPMC, Sorbonne Universités, Paris, France
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30
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Xu L, Van Doorn S, Hildenbrandt H, Etienne RS. Inferring the Effect of Species Interactions on Trait Evolution. Syst Biol 2020; 70:463-479. [PMID: 32960972 PMCID: PMC8048392 DOI: 10.1093/sysbio/syaa072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 09/01/2020] [Accepted: 09/08/2020] [Indexed: 11/18/2022] Open
Abstract
Models of trait evolution form an important part of macroevolutionary biology. The Brownian motion model and Ornstein–Uhlenbeck models have become classic (null) models of character evolution, in which species evolve independently. Recently, models incorporating species interactions have been developed, particularly involving competition where abiotic factors pull species toward an optimal trait value and competitive interactions drive the trait values apart. However, these models assume a fitness function rather than derive it from population dynamics and they do not consider dynamics of the trait variance. Here, we develop a general coherent trait evolution framework where the fitness function is based on a model of population dynamics, and therefore it can, in principle, accommodate any type of species interaction. We illustrate our framework with a model of abundance-dependent competitive interactions against a macroevolutionary background encoded in a phylogenetic tree. We develop an inference tool based on Approximate Bayesian Computation and test it on simulated data (of traits at the tips). We find that inference performs well when the diversity predicted by the parameters equals the number of species in the phylogeny. We then fit the model to empirical data of baleen whale body lengths, using three different summary statistics, and compare it to a model without population dynamics and a model where competition depends on the total metabolic rate of the competitors. We show that the unweighted model performs best for the least informative summary statistic, while the model with competition weighted by the total metabolic rate fits the data slightly better than the other two models for the two more informative summary statistics. Regardless of the summary statistic used, the three models substantially differ in their predictions of the abundance distribution. Therefore, data on abundance distributions will allow us to better distinguish the models from one another, and infer the nature of species interactions. Thus, our framework provides a conceptual approach to reveal species interactions underlying trait evolution and identifies the data needed to do so in practice. [Approximate Bayesian computation; competition; phylogeny; population dynamics; simulations; species interaction; trait evolution.]
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Affiliation(s)
- Liang Xu
- Faculty of Science and Engineering, Groningen Institute for Evolutionary Life Sciences, University of Groningen, PO Box 11103, Groningen 9700 CC, The Netherlands
| | - Sander Van Doorn
- Faculty of Science and Engineering, Groningen Institute for Evolutionary Life Sciences, University of Groningen, PO Box 11103, Groningen 9700 CC, The Netherlands
| | - Hanno Hildenbrandt
- Faculty of Science and Engineering, Groningen Institute for Evolutionary Life Sciences, University of Groningen, PO Box 11103, Groningen 9700 CC, The Netherlands
| | - Rampal S Etienne
- Faculty of Science and Engineering, Groningen Institute for Evolutionary Life Sciences, University of Groningen, PO Box 11103, Groningen 9700 CC, The Netherlands
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31
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Campione NE, Evans DC. The accuracy and precision of body mass estimation in non-avian dinosaurs. Biol Rev Camb Philos Soc 2020; 95:1759-1797. [PMID: 32869488 DOI: 10.1111/brv.12638] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 07/06/2020] [Accepted: 07/07/2020] [Indexed: 12/20/2022]
Abstract
Inferring the body mass of fossil taxa, such as non-avian dinosaurs, provides a powerful tool for interpreting physiological and ecological properties, as well as the ability to study these traits through deep time and within a macroevolutionary context. As a result, over the past 100 years a number of studies advanced methods for estimating mass in dinosaurs and other extinct taxa. These methods can be categorized into two major approaches: volumetric-density (VD) and extant-scaling (ES). The former receives the most attention in non-avian dinosaurs and advanced appreciably over the last century: from initial physical scale models to three-dimensional (3D) virtual techniques that utilize scanned data obtained from entire skeletons. The ES approach is most commonly applied to extinct members of crown clades but some equations are proposed and utilized in non-avian dinosaurs. Because both approaches share a common goal, they are often viewed in opposition to one another. However, current palaeobiological research problems are often approach specific and, therefore, the decision to utilize a VD or ES approach is largely question dependent. In general, biomechanical and physiological studies benefit from the full-body reconstruction provided through a VD approach, whereas large-scale evolutionary and ecological studies require the extensive data sets afforded by an ES approach. This study summarizes both approaches to body mass estimation in stem-group taxa, specifically non-avian dinosaurs, and provides a comparative quantitative framework to reciprocally illuminate and corroborate VD and ES approaches. The results indicate that mass estimates are largely consistent between approaches: 73% of VD reconstructions occur within the expected 95% prediction intervals of the ES relationship. However, almost three quarters of outliers occur below the lower 95% prediction interval, indicating that VD mass estimates are, on average, lower than would be expected given their stylopodial circumferences. Inconsistencies (high residual and per cent prediction deviation values) are recovered to a varying degree among all major dinosaurian clades along with an overall tendency for larger deviations between approaches among small-bodied taxa. Nonetheless, our results indicate a strong corroboration between recent iterations of the VD approach based on 3D specimen scans suggesting that our current understanding of size in dinosaurs, and hence its biological correlates, has improved over time. We advance that VD and ES approaches have fundamentally (metrically) different advantages and, hence, the comparative framework used and advocated here combines the accuracy afforded by ES with the precision provided by VD and permits the rapid identification of discrepancies with the potential to open new areas of discussion.
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Affiliation(s)
- Nicolás E Campione
- Palaeoscience Research Centre, University of New England, Armidale, New South Wales, 2351, Australia
| | - David C Evans
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks St, Toronto, Ontario, M5S 3B2, Canada.,Department of Natural History, Royal Ontario Museum, 100 Queen's Park, Toronto, Ontario, M5S 2C6, Canada
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32
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Womack MC, Bell RC. Two-hundred million years of anuran body-size evolution in relation to geography, ecology and life history. J Evol Biol 2020; 33:1417-1432. [PMID: 32672849 DOI: 10.1111/jeb.13679] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Accepted: 07/07/2020] [Indexed: 01/08/2023]
Abstract
Surprisingly, little is known about body-size evolution within the most diverse amphibian order, anurans (frogs and toads), despite known effects of body size on the physiological, ecological and life-history traits of animals more generally. Here, we examined anuran body-size evolution among 2,434 species with over 200 million years of shared evolutionary history. We found clade-specific evolutionary shifts to new body-size optima along with numerous independent transitions to gigantic and miniature body sizes, despite the upper limits of anuran body size remaining quite consistent throughout the fossil record. We found a weak, positive correlation between a species' body size and maximum latitude and elevation, including a dearth of small species at higher elevations and broader latitudinal and elevational ranges in larger anurans. Although we found modest differences in mean anuran body size among microhabitats, there was extensive overlap in the range of body sizes across microhabitats. Finally, we found that larger anurans are more likely to consume vertebrate prey than smaller anurans are and that species with a free-swimming larval phase during development are larger on average than those in which development into a froglet occurs within the egg. Overall, anuran body size does not conform to geographic and ecological patterns observed in other tetrapods but is perhaps more notable for variation in body size within geographic regions, ecologies and life histories. Here, we document this variation and propose target clades for detailed studies aimed at disentangling how and why variation in body size was generated and is maintained in anurans.
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Affiliation(s)
- Molly C Womack
- Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, District of Columbia, USA.,Department of Biology, Utah State University, Logan, Utah, USA
| | - Rayna C Bell
- Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, District of Columbia, USA.,Herpetology Department, California Academy of Sciences, San Francisco, California, USA
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33
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Abstract
AbstractHuman-mediated species invasion and climate change are leading to global extinctions and are predicted to result in the loss of important axes of phylogenetic and functional diversity. However, the long-term robustness of modern communities to invasion is unknown, given the limited timescales over which they can be studied. Using the fossil record of the Paleocene-Eocene thermal maximum (PETM; ∼56 Ma) in North America, we evaluate mammalian community-level response to a rapid global warming event (5°-8°C) and invasion by three Eurasian mammalian orders and by species undergoing northward range shifts. We assembled a database of 144 species body sizes and created a time-scaled composite phylogeny. We calculated the phylogenetic and functional diversity of all communities before, during, and after the PETM. Despite increases in the phylogenetic diversity of the regional species pool, phylogenetic diversity of mammalian communities remained relatively unchanged, a pattern that is invariant to the tree dating method, uncertainty in tree topology, and resolution. Similarly, body size dispersion and the degree of spatial taxonomic turnover of communities remained similar across the PETM. We suggest that invasion by new taxa had little impact on Paleocene-Eocene mammal communities because niches were not saturated. Our findings are consistent with the numerous studies of modern communities that record little change in community-scale richness despite turnover in taxonomic composition during invasion. What remains unknown is whether long-term robustness to biotic and abiotic perturbation are retained by modern communities given global anthropogenic landscape modification.
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34
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The grass squid Pickfordiateuthis pulchella is a paedomorphic loliginid. Mol Phylogenet Evol 2020; 147:106801. [DOI: 10.1016/j.ympev.2020.106801] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 03/03/2020] [Accepted: 03/18/2020] [Indexed: 11/23/2022]
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Brown CM, Greenwood DR, Kalyniuk JE, Braman DR, Henderson DM, Greenwood CL, Basinger JF. Dietary palaeoecology of an Early Cretaceous armoured dinosaur (Ornithischia; Nodosauridae) based on floral analysis of stomach contents. ROYAL SOCIETY OPEN SCIENCE 2020; 7:200305. [PMID: 32742695 PMCID: PMC7353971 DOI: 10.1098/rsos.200305] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 05/18/2020] [Indexed: 05/02/2023]
Abstract
The exceptionally well-preserved holotype of the armoured dinosaur Borealopelta markmitchelli (Ornithischia; Nodosauridae) from the Early Cretaceous (Clearwater Formation) of northern Alberta preserves a distinct mass within the abdominal cavity. Fourteen independent criteria (including: co-allochthony, anatomical position, gastroliths) support the interpretation of this mass as ingested stomach contents-a cololite. Palynomorphs in the cololite are a subset of the more diverse external sample. Analysis of the cololite documents well-preserved plant material dominated by leaf tissue (88%), including intact sporangia, leaf cross-sections and cuticle, but also including stems, wood and charcoal. The leaf fraction is dominated (85%) by leptosporangiate ferns (subclass Polypodiidae), with low cycad-cycadophyte (3%) and trace conifer foliage. These data represent the most well-supported and detailed direct evidence of diet in an herbivorous dinosaur. Details of the dietary palaeoecology of this nodosaur are revealed, including: selective feeding on ferns; preferential ingestion of leptosporangiate ferns to the exclusion of Osmundaceae and eusporangiate ferns such as Marattiaceae; and incidental consumption of cycad-cycadophyte and conifer leaves. The presence of significant (6%) charcoal may represent the dietary use of recently burned conifer forest undergoing fern succession, early evidence of a fire succession ecology, as is associated with many modern large herbivores.
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Affiliation(s)
- Caleb M. Brown
- Royal Tyrrell Museum of Palaeontology, Drumheller, Alberta, CanadaT0J 0Y0
- Author for correspondence: Caleb M. Brown e-mail:
| | - David R. Greenwood
- Department of Biology, Brandon University, Brandon, Manitoba, CanadaR7A 6A9
| | | | - Dennis R. Braman
- Royal Tyrrell Museum of Palaeontology, Drumheller, Alberta, CanadaT0J 0Y0
| | | | - Cathy L. Greenwood
- Department of Biology, Brandon University, Brandon, Manitoba, CanadaR7A 6A9
| | - James F. Basinger
- Department of Geological Sciences, University of Saskatchewan, Saskatoon, Saskatchewan, CanadaS7N 5E2
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Benevento GL, Benson RBJ, Friedman M. Patterns of mammalian jaw ecomorphological disparity during the Mesozoic/Cenozoic transition. Proc Biol Sci 2020; 286:20190347. [PMID: 31039714 PMCID: PMC6532522 DOI: 10.1098/rspb.2019.0347] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The radiation of mammals after the Cretaceous/Palaeogene (K/Pg) boundary was a major event in the evolution of terrestrial ecosystems. Multiple studies point to increases in maximum body size and body size disparity, but patterns of disparity for other traits are less clear owing to a focus on different indices and subclades. We conducted an inclusive comparison of jaw functional disparity from the Early Jurassic-latest Eocene, using six mechanically relevant mandibular ratios for 256 species representing all major groups. Jaw functional disparity across all mammals was low throughout much of the Mesozoic and remained low across the K/Pg boundary. Nevertheless, the K/Pg boundary was characterized by a pronounced pattern of turnover and replacement, entailing a substantial reduction of non-therian and stem-therian disparity, alongside a marked increase in that of therians. Total mammal disparity exceeded its Mesozoic maximum for the first time during the Eocene, when therian mammals began exploring previously unoccupied regions of function space. This delay in the rise of jaw functional disparity until the Eocene probably reflects the duration of evolutionary recovery after the K/Pg mass extinction event. This contrasts with the more rapid expansion of maximum body size, which occurred in the Palaeocene.
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Affiliation(s)
- Gemma Louise Benevento
- 1 Department of Earth Sciences, University of Oxford , Oxford OX1 3AN , UK.,2 School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston , Birmingham B15 2TT , UK
| | - Roger B J Benson
- 1 Department of Earth Sciences, University of Oxford , Oxford OX1 3AN , UK
| | - Matt Friedman
- 1 Department of Earth Sciences, University of Oxford , Oxford OX1 3AN , UK.,3 Museum of Paleontology and Department of Earth and Environmental Sciences, University of Michigan , 1105 N University Avenue, Ann Arbor, MI 48109 , USA
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37
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Comparing Rates of Linage Diversification with Rates of Size and Shape Evolution in Catarrhine Crania. Evol Biol 2020. [DOI: 10.1007/s11692-020-09500-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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38
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Sandom CJ, Middleton O, Lundgren E, Rowan J, Schowanek SD, Svenning JC, Faurby S. Trophic rewilding presents regionally specific opportunities for mitigating climate change. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190125. [PMID: 31983340 PMCID: PMC7017765 DOI: 10.1098/rstb.2019.0125] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/21/2019] [Indexed: 01/09/2023] Open
Abstract
Large-bodied mammalian herbivores can influence processes that exacerbate or mitigate climate change. Herbivore impacts are, in turn, influenced by predators that place top-down forcing on prey species within a given body size range. Here, we explore how the functional composition of terrestrial large-herbivore and -carnivore guilds varies between three mammal distribution scenarios: Present-Natural, Current-Day and Extant-Native Trophic (ENT) Rewilding. Considering the effects of herbivore species weakly influenced by top-down forcing, we quantify the relative influence keystone large-herbivore guilds have on methane emissions, woody vegetation expansion, fire dynamics, large-seed dispersal, and nitrogen and phosphorus transport potential. We find strong regional differences in the number of herbivores under weak top-down regulation between our three scenarios, with important implications for how they will influence climate change relevant processes. Under the Present-Natural non-ruminant, megaherbivore, browsers were a particularly important guild across much of the world. Megaherbivore extinction and range contraction and the arrival of livestock mean large, ruminant, grazers have become more dominant. ENT Rewilding can restore the Afrotropics and the Indo-Malay realm to the Present-Natural benchmark, but causes top-down forcing of the largest herbivores to become commonplace elsewhere. ENT Rewilding will reduce methane emissions, but does not maximize natural climate solution potential. This article is part of the theme issue 'Climate change and ecosystems: threats, opportunities and solutions'.
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Affiliation(s)
- Christopher J. Sandom
- School of Life Sciences, University of Sussex, Brighton BN1 9QG, UK
- Sussex Sustainability Research Programme (SSRP), University of Sussex, Brighton BN1 9QG, UK
| | - Owen Middleton
- School of Life Sciences, University of Sussex, Brighton BN1 9QG, UK
| | - Erick Lundgren
- Centre for Compassionate Conservation, School of Life Sciences, University of Technology, Sydney, Australia
| | - John Rowan
- Department of Anthropology, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Simon D. Schowanek
- Section for Ecoinformatics and Biodiversity, Department of Bioscience, Aarhus University, Ny Munkegade 114, DK-8000 Aarhus C, Denmark
- Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Aarhus University, Aarhus, Denmark
| | - Jens-Christian Svenning
- Section for Ecoinformatics and Biodiversity, Department of Bioscience, Aarhus University, Ny Munkegade 114, DK-8000 Aarhus C, Denmark
- Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Aarhus University, Aarhus, Denmark
| | - Søren Faurby
- Department of Biological and Environmental Sciences, University of Gothenburg, Box 461, SE 405 30, Göteborg, Sweden
- Gothenburg Global Biodiversity Centre, Box 461, SE 405 30, Göteborg, Sweden
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39
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Divergent mammalian body size in a stable Eocene greenhouse climate. Sci Rep 2020; 10:3987. [PMID: 32132560 PMCID: PMC7055232 DOI: 10.1038/s41598-020-60379-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Accepted: 01/21/2020] [Indexed: 11/08/2022] Open
Abstract
A negative correlation between body size and the latitudinal temperature gradient is well established for extant terrestrial endotherms but less so in the fossil record. Here we analyze the middle Eocene site of Geiseltal (Germany), whose record is considered to span ca. 5 Myrs of gradual global cooling, and generate one of the most extensive mammalian Paleogene body size datasets outside North America. The δ18O and δ13C isotopic analysis of bioapatite reveals signatures indicative of a humid, subtropical forest with no apparent climatic change across Geiseltal. Yet, body mass of hippomorphs and tapiromorphs diverges rapidly from a respective median body size of 39 kg and 124 kg at the base of the succession to 26 kg and 223 kg at the top. We attribute the divergent body mass evolution to a disparity in lifestyle, in which both taxa maximize their body size-related selective advantages. Our results therefore support the view that intrinsic biotic processes are an important driver of body mass outside of abrupt climate events. Moreover, the taxonomy previously used to infer the duration of the Geiseltal biota is not reproducible, which precludes chronological correlation with Eocene marine temperature curves.
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40
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Affiliation(s)
- R. M. Sibly
- School of Biological Sciences University of Reading Reading UK
| | - J. H. Brown
- Biology Department University of New Mexico Albuquerque NM USA
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41
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Wang M, Chen K, Guo D, Luo B, Wang W, Gao H, Liu Y, Feng J. Ambient temperature correlates with geographic variation in body size of least horseshoe bats. Curr Zool 2020; 66:459-465. [PMID: 33293926 PMCID: PMC7705506 DOI: 10.1093/cz/zoaa004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 02/02/2020] [Indexed: 11/13/2022] Open
Abstract
Geographic variation in body size is common within many animal species. The causes of this pattern, however, remain largely unexplored in most vertebrate groups. Bats are widely distributed globally owing to their ability of powered flight. Most bat species encounter a variety of climatic conditions across their distribution range, making them an ideal taxon for the study of ecogeographic patterns in body size. Here, we used adult least horseshoe bats, Rhinolophus pusillus, to test whether geographic variation in body size was determined by heat conservation, heat dissipation, climatic seasonality, or primary productivity. We measured body mass and head-body length for 246 adult bats from 12 allopatric colonies in China. We quantified the ecological conditions inhabited by each colony, including mean maximum temperature of the warmest month, mean minimum temperature of the coldest month, temperature seasonality, precipitation seasonality, and annual net primary productivity (ANPP). Body mass and head-body length, 2 of the most reliable indicators of body size, exhibited marked differences between colonies. After controlling for spatial autocorrelation, the mean minimum temperature of the coldest month explained most of the variation in body size among colonies, regardless of sex. The mean maximum temperature, climatic seasonality, and ANPP had limited power in predicting body size of males or females in comparison with mean minimum temperature. These results support the heat conservation hypothesis and suggest adaptive responses of body size to cold climates in cave-dwelling bats.
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Affiliation(s)
- Man Wang
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, 2555 Jingyue Street, Changchun 130117, China.,Key Laboratory of Southwest China Wildlife Resources Conservation of Ministry of Education, China West Normal University, 1# Shida Road, Nanchong 637009, China
| | - Kelly Chen
- College of Veterinary Medicine, University of Illinois at Champaign-Urbana, 2001 S. Lincoln Avenue, Urbana, IL, USA
| | - Dongge Guo
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, 2555 Jingyue Street, Changchun 130117, China
| | - Bo Luo
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, 2555 Jingyue Street, Changchun 130117, China.,Key Laboratory of Southwest China Wildlife Resources Conservation of Ministry of Education, China West Normal University, 1# Shida Road, Nanchong 637009, China
| | - Weiwei Wang
- Key Laboratory of Southwest China Wildlife Resources Conservation of Ministry of Education, China West Normal University, 1# Shida Road, Nanchong 637009, China
| | - Huimin Gao
- Key Laboratory of Southwest China Wildlife Resources Conservation of Ministry of Education, China West Normal University, 1# Shida Road, Nanchong 637009, China
| | - Ying Liu
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, 2555 Jingyue Street, Changchun 130117, China
| | - Jiang Feng
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, 2555 Jingyue Street, Changchun 130117, China.,College of Life Science, Jilin Agricultural University, 2888 Xincheng street, Changchun 130118, China
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42
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The Natural Selection of Metabolism Explains Curvature in Fossil Body Mass Evolution. Evol Biol 2020. [DOI: 10.1007/s11692-020-09493-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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43
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Grossnickle DM. Feeding ecology has a stronger evolutionary influence on functional morphology than on body mass in mammals. Evolution 2020; 74:610-628. [PMID: 31967667 DOI: 10.1111/evo.13929] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 12/27/2019] [Accepted: 01/14/2020] [Indexed: 01/02/2023]
Abstract
Ecological specialization is a central driver of adaptive evolution. However, selective pressures may uniquely affect different ecomorphological traits (e.g., size and shape), complicating efforts to investigate the role of ecology in generating phenotypic diversity. Comparative studies can help remedy this issue by identifying specific relationships between ecologies and morphologies, thus elucidating functionally relevant traits. Jaw shape is a dietary correlate that offers considerable insight on mammalian evolution, but few studies have examined the influence of diet on jaw morphology across mammals. To this end, I apply phylogenetic comparative methods to mandibular measurements and dietary data for a diverse sample of mammals. Especially powerful predictors of diet are metrics that capture either the size of the angular process, which increases with greater herbivory, or the length of the posterior portion of the jaw, which decreases with greater herbivory. The size of the angular process likely reflects sizes of attached muscles that produce jaw movements needed to grind plant material. Further, I examine the impact of feeding ecology on body mass, an oft-used ecological surrogate in macroevolutionary studies. Although body mass commonly increases with evolutionary shifts to herbivory, it is outperformed by functional jaw morphology as a predictor of diet. Body mass is influenced by numerous factors beyond diet, and it may be evolutionarily labile relative to functional morphologies. This suggests that ecological diversification events may initially facilitate body mass diversification at smaller taxonomic and temporal scales, but sustained selective pressures will subsequently drive greater trait partitioning in functional morphologies.
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44
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Cassini MH. A mixed model of the evolution of polygyny and sexual size dimorphism in mammals. Mamm Rev 2019. [DOI: 10.1111/mam.12171] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Marcelo H. Cassini
- Laboratorio de Biología del Comportamiento IBYME CONICET Obligado 2490, 1429 Buenos Aires Argentina
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45
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Stefanic CM, Nesbitt SJ. The evolution and role of the hyposphene-hypantrum articulation in Archosauria: phylogeny, size and/or mechanics? ROYAL SOCIETY OPEN SCIENCE 2019; 6:190258. [PMID: 31824685 PMCID: PMC6837189 DOI: 10.1098/rsos.190258] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 08/22/2019] [Indexed: 06/10/2023]
Abstract
Living members of Archosauria, the reptile clade containing Crocodylia and Aves, have a wide range of skeletal morphologies, ecologies and body size. The range of body size greatly increases when extinct archosaurs are included, because extinct Archosauria includes the largest members of any terrestrial vertebrate group (e.g. 70-tonne titanosaurs, 20-tonne theropods). Archosaurs evolved various skeletal adaptations for large body size, but these adaptations varied among clades and did not always appear consistently with body size or ecology. Modification of intervertebral articulations, specifically the presence of a hyposphene-hypantrum articulation between trunk vertebrae, occurs in a variety of extinct archosaurs (e.g. non-avian dinosaurs, pseudosuchians). We surveyed the phylogenetic distribution of the hyposphene-hypantrum to test its relationship with body size. We found convergent evolution among large-bodied clades, except when the clade evolved an alternative mechanism for vertebral bracing. For example, some extinct lineages that lack the hyposphene-hypantrum articulation (e.g. ornithischians) have ossified tendons that braced their vertebral column. Ossified tendons are present even in small taxa and in small-bodied juveniles, but large-bodied taxa with ossified tendons reached those body sizes without evolving the hyposphene-hypantrum articulation. The hyposphene-hypantrum was permanently lost in extinct crownward members of both major archosaur lineages (i.e. Crocodylia and Aves) as they underwent phyletic size decrease, changes in vertebral morphology and shifts in ecology.
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Affiliation(s)
- Candice M. Stefanic
- Department of Geosciences, Virginia Tech, Blacksburg, VA 24061, USA
- Department of Anatomical Sciences, Stony Brook University, Stony Brook, NY 11794, USA
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46
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Jame C, Tissier J, Maridet O, Becker D. Early Agenian rhinocerotids from Wischberg (Canton Bern, Switzerland) and clarification of the systematics of the genus Diaceratherium. PeerJ 2019; 7:e7517. [PMID: 31523499 PMCID: PMC6717501 DOI: 10.7717/peerj.7517] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 07/19/2019] [Indexed: 12/03/2022] Open
Abstract
Background Wischberg is a Swiss locality in Bern Canton which has yielded numerous vertebrates remains from the earliest Miocene (= MN1). It has a very rich faunal diversity, one of the richest in Switzerland for this age. Among all the mammals reported in the original faunal list 70 years ago, three rhinocerotid species were identified. The material consists of two fragmentary skulls, cranial fragments, several mandibles, teeth and postcranial bones, in a rather good state of preservation. Results After reexamination of the material from this locality (curated in three different Swiss museums) and comparison with holotype specimens, we show that all rhinocerotid specimens from Wischberg can be referred to two species only. Most of the material can be attributed to the large-sized teleoceratine Diaceratherium lemanense, while only a few specimens, including a skull and mandible, belong to the much smaller sized Pleuroceros pleuroceros. We describe and illustrate for the first time most of these fossil remains. However, the systematics of the genus Diaceratherium is currently controversial, and based on our new observations we consider seven species as valid, though a large-scale phylogenetic study should be done in the future to resolve it. The rhinocerotid association found in Wischberg is nonetheless typical of the MN1 biozone, which results from a faunal renewal occurring just before the end of the Oligocene.
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Affiliation(s)
- Claire Jame
- Observatoire des Sciences de l'Univers de Rennes, Université Rennes I, Rennes, France
| | - Jérémy Tissier
- Cenozoic Research Group, JURASSICA Museum, Porrentruy, Switzerland.,Department of Geosciences, University of Fribourg, Fribourg, Switzerland
| | - Olivier Maridet
- Cenozoic Research Group, JURASSICA Museum, Porrentruy, Switzerland.,Department of Geosciences, University of Fribourg, Fribourg, Switzerland
| | - Damien Becker
- Cenozoic Research Group, JURASSICA Museum, Porrentruy, Switzerland.,Department of Geosciences, University of Fribourg, Fribourg, Switzerland
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47
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Condamine FL, Rolland J, Morlon H. Assessing the causes of diversification slowdowns: temperature‐dependent and diversity‐dependent models receive equivalent support. Ecol Lett 2019; 22:1900-1912. [DOI: 10.1111/ele.13382] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 02/20/2019] [Accepted: 08/12/2019] [Indexed: 12/30/2022]
Affiliation(s)
- Fabien L. Condamine
- CNRS, UMR 5554 Institut des Sciences de l'Evolution de Montpellier Place Eugène Bataillon 34095Montpellier France
- CNRS, UMR 7641 Centre de Mathématiques Appliquées (Ecole Polytechnique) route de Saclay 91128Palaiseau France
| | - Jonathan Rolland
- CNRS, UMR 7641 Centre de Mathématiques Appliquées (Ecole Polytechnique) route de Saclay 91128Palaiseau France
- Department of Computational Biology, Biophore University of Lausanne Lausanne 1015Switzerland
- Department of Zoology University of British Columbia University Blvd #4200‐6270Vancouver B.C Canada
| | - Hélène Morlon
- CNRS, UMR 7641 Centre de Mathématiques Appliquées (Ecole Polytechnique) route de Saclay 91128Palaiseau France
- IBENS, Département de Biologie, Ecole Normale Supérieure, CNRS, Inserm, PSL Research University F‐75005Paris France
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48
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Godoy PL, Benson RBJ, Bronzati M, Butler RJ. The multi-peak adaptive landscape of crocodylomorph body size evolution. BMC Evol Biol 2019; 19:167. [PMID: 31390981 PMCID: PMC6686447 DOI: 10.1186/s12862-019-1466-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 06/24/2019] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Little is known about the long-term patterns of body size evolution in Crocodylomorpha, the > 200-million-year-old group that includes living crocodylians and their extinct relatives. Extant crocodylians are mostly large-bodied (3-7 m) predators. However, extinct crocodylomorphs exhibit a wider range of phenotypes, and many of the earliest taxa were much smaller (< 1.2 m). This suggests a pattern of size increase through time that could be caused by multi-lineage evolutionary trends of size increase or by selective extinction of small-bodied species. Here, we characterise patterns of crocodylomorph body size evolution using a model fitting-approach (with cranial measurements serving as proxies). We also estimate body size disparity through time and quantitatively test hypotheses of biotic and abiotic factors as potential drivers of crocodylomorph body size evolution. RESULTS Crocodylomorphs reached an early peak in body size disparity during the Late Jurassic, and underwent an essentially continual decline since then. A multi-peak Ornstein-Uhlenbeck model outperforms all other evolutionary models fitted to our data (including both uniform and non-uniform), indicating that the macroevolutionary dynamics of crocodylomorph body size are better described within the concept of an adaptive landscape, with most body size variation emerging after shifts to new macroevolutionary regimes (analogous to adaptive zones). We did not find support for a consistent evolutionary trend towards larger sizes among lineages (i.e., Cope's rule), or strong correlations of body size with climate. Instead, the intermediate to large body sizes of some crocodylomorphs are better explained by group-specific adaptations. In particular, the evolution of a more aquatic lifestyle (especially marine) correlates with increases in average body size, though not without exceptions. CONCLUSIONS Shifts between macroevolutionary regimes provide a better explanation of crocodylomorph body size evolution on large phylogenetic and temporal scales, suggesting a central role for lineage-specific adaptations rather than climatic forcing. Shifts leading to larger body sizes occurred in most aquatic and semi-aquatic groups. This, combined with extinctions of groups occupying smaller body size regimes (particularly during the Late Cretaceous and Cenozoic), gave rise to the upward-shifted body size distribution of extant crocodylomorphs compared to their smaller-bodied terrestrial ancestors.
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Affiliation(s)
- Pedro L Godoy
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham, UK. .,Present Address: Department of Anatomical Sciences, Stony Brook University, Stony Brook, NY, 11794, USA.
| | | | - Mario Bronzati
- Laboratório de Paleontologia de Ribeirão Preto, FFCLRP, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Richard J Butler
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham, UK
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49
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Grossnickle DM, Smith SM, Wilson GP. Untangling the Multiple Ecological Radiations of Early Mammals. Trends Ecol Evol 2019; 34:936-949. [PMID: 31229335 DOI: 10.1016/j.tree.2019.05.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 05/14/2019] [Accepted: 05/21/2019] [Indexed: 11/16/2022]
Abstract
The ecological diversification of early mammals is one of the most globally transformative events in Earth's history and the Cretaceous Terrestrial Revolution (KTR) and end-Cretaceous mass extinction are commonly hailed as catalysts. However, a confounding issue when examining this diversification is that it comprised nested radiations of mammalian subclades within the broader scope of mammalian evolution. In the past 200 million years, various independent groups experienced large-scale radiations, each involving ecological diversification from ancestral lineages of small insectivores; examples include Jurassic mammaliaforms, Late Cretaceous metatherians, and Cenozoic placentals. Here, we review these ecological radiations, highlighting the nuanced complexity of early mammal evolution, the value of ecomorphological fossil data, and the importance of phylogenetic context in macroevolutionary studies.
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Affiliation(s)
| | - Stephanie M Smith
- Integrative Research Center, Field Museum of Natural History, Chicago, IL, USA
| | - Gregory P Wilson
- Department of Biology, University of Washington, Seattle, WA, USA
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50
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Sixty-six million years along the road of mammalian ecomorphological specialization. Proc Natl Acad Sci U S A 2019; 116:12698-12703. [PMID: 31182613 DOI: 10.1073/pnas.1821825116] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The fossil record of the large terrestrial mammals of the North American Cenozoic has previously been quantitatively summarized in six sequential episodes of faunal associations-"evolutionary faunas"-that correspond well with previously proposed qualitative "Chronofaunas." Here, we investigate the ecological spectrum of these faunas by classifying their major taxonomic components into discrete ecomorphological categories of diet, locomotion, and body size. To specifically address the potential influence of long-term climatic shifts on the ecomorphological composition of these faunas, we analyze via contingency tables and detrended correspondence analyses the frequency distribution of ecomorph types within faunas. We show that each evolutionary fauna has a unique, nonrandom association of ecomorphs, and we identify a long-term trend toward greater ecomorphological specialization over successive faunas during the past 66 My. Major vegetation shifts induced by climatic changes appear to underlie the ecomorphological dynamics of these six temporal associations that summarize Cenozoic North American mammalian evolutionary history.
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