1
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Sansalone G, Wroe S, Coates G, Attard MRG, Fruciano C. Unexpectedly uneven distribution of functional trade-offs explains cranial morphological diversity in carnivores. Nat Commun 2024; 15:3275. [PMID: 38627430 PMCID: PMC11021405 DOI: 10.1038/s41467-024-47620-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 04/08/2024] [Indexed: 04/19/2024] Open
Abstract
Functional trade-offs can affect patterns of morphological and ecological evolution as well as the magnitude of morphological changes through evolutionary time. Using morpho-functional landscape modelling on the cranium of 132 carnivore species, we focused on the macroevolutionary effects of the trade-off between bite force and bite velocity. Here, we show that rates of evolution in form (morphology) are decoupled from rates of evolution in function. Further, we found theoretical morphologies optimising for velocity to be more diverse, while a much smaller phenotypic space was occupied by shapes optimising force. This pattern of differential representation of different functions in theoretical morphological space was highly correlated with patterns of actual morphological disparity. We hypothesise that many-to-one mapping of cranium shape on function may prevent the detection of direct relationships between form and function. As comparatively only few morphologies optimise bite force, species optimising this function may be less abundant because they are less likely to evolve. This, in turn, may explain why certain clades are less variable than others. Given the ubiquity of functional trade-offs in biological systems, these patterns may be general and may help to explain the unevenness of morphological and functional diversity across the tree of life.
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Affiliation(s)
- Gabriele Sansalone
- Institute for Marine Biological Resources and Biotechnology (CNR-IRBIM), National Research Council, Via S. Raineri 4, 98122, Messina, Italy.
- Function, Evolution and Anatomy Research Lab, Zoology Division, School of Environmental and Rural Science, University of New England, Armidale, NSW, Australia.
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Campi 213D, 41125, Modena, Italy.
| | - Stephen Wroe
- Function, Evolution and Anatomy Research Lab, Zoology Division, School of Environmental and Rural Science, University of New England, Armidale, NSW, Australia
| | - Geoffrey Coates
- Function, Evolution and Anatomy Research Lab, Zoology Division, School of Environmental and Rural Science, University of New England, Armidale, NSW, Australia
| | - Marie R G Attard
- Function, Evolution and Anatomy Research Lab, Zoology Division, School of Environmental and Rural Science, University of New England, Armidale, NSW, Australia
- British Antarctic Survey, High Cross, Madingley Road, CB3 0ET, Cambridge, UK
| | - Carmelo Fruciano
- Institute for Marine Biological Resources and Biotechnology (CNR-IRBIM), National Research Council, Via S. Raineri 4, 98122, Messina, Italy.
- National Biodiversity Future Center, Piazza Marina 61, 90133, Palermo, Italy.
- Department of Biological, Geological and Environmental Sciences, University of Catania, via Androne 81, 95124, Catania, Italy.
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2
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Meade LE, Pittman M, Balanoff A, Lautenschlager S. Cranial functional specialisation for strength precedes morphological evolution in Oviraptorosauria. Commun Biol 2024; 7:436. [PMID: 38600295 PMCID: PMC11006937 DOI: 10.1038/s42003-024-06137-1] [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: 01/22/2024] [Accepted: 04/02/2024] [Indexed: 04/12/2024] Open
Abstract
Oviraptorosaurians were a theropod dinosaur group that reached high diversity in the Late Cretaceous. Within oviraptorosaurians, the later diverging oviraptorids evolved distinctive crania which were extensively pneumatised, short and tall, and had a robust toothless beak, interpreted as providing a powerful bite for their herbivorous to omnivorous diet. The present study explores the ability of oviraptorid crania to resist large mechanical stresses compared with other theropods and where this adaptation originated within oviraptorosaurians. Digital 3D cranial models were constructed for the earliest diverging oviraptorosaurian, Incisivosaurus gauthieri, and three oviraptorids, Citipati osmolskae, Conchoraptor gracilis, and Khaan mckennai. Finite element analyses indicate oviraptorosaurian crania were stronger than those of other herbivorous theropods (Erlikosaurus and Ornithomimus) and were more comparable to the large, carnivorous Allosaurus. The cranial biomechanics of Incisivosaurus align with oviraptorids, indicating an early establishment of distinctive strengthened cranial biomechanics in Oviraptorosauria, even before the highly modified oviraptorid cranial morphology. Bite modelling, using estimated muscle forces, suggests oviraptorid crania may have functioned closer to structural safety limits. Low mechanical stresses around the beaks of oviraptorids suggest a convergently evolved, functionally distinct rhamphotheca, serving as a cropping/feeding tool rather than for stress reduction, when compared with other herbivorous theropods.
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Affiliation(s)
- Luke E Meade
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham, UK.
| | - Michael Pittman
- School of Life Sciences, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Amy Balanoff
- Center for Functional Anatomy and Evolution, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Stephan Lautenschlager
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham, UK
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3
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Mitchell DR, Sherratt E, Weisbecker V. Facing the facts: adaptive trade-offs along body size ranges determine mammalian craniofacial scaling. Biol Rev Camb Philos Soc 2024; 99:496-524. [PMID: 38029779 DOI: 10.1111/brv.13032] [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: 03/27/2023] [Revised: 11/12/2023] [Accepted: 11/14/2023] [Indexed: 12/01/2023]
Abstract
The mammalian cranium (skull without lower jaw) is representative of mammalian diversity and is thus of particular interest to mammalian biologists across disciplines. One widely retrieved pattern accompanying mammalian cranial diversification is referred to as 'craniofacial evolutionary allometry' (CREA). This posits that adults of larger species, in a group of closely related mammals, tend to have relatively longer faces and smaller braincases. However, no process has been officially suggested to explain this pattern, there are many apparent exceptions, and its predictions potentially conflict with well-established biomechanical principles. Understanding the mechanisms behind CREA and causes for deviations from the pattern therefore has tremendous potential to explain allometry and diversification of the mammalian cranium. Here, we propose an amended framework to characterise the CREA pattern more clearly, in that 'longer faces' can arise through several kinds of evolutionary change, including elongation of the rostrum, retraction of the jaw muscles, or a more narrow or shallow skull, which all result in a generalised gracilisation of the facial skeleton with increased size. We define a standardised workflow to test for the presence of the pattern, using allometric shape predictions derived from geometric morphometrics analysis, and apply this to 22 mammalian families including marsupials, rabbits, rodents, bats, carnivores, antelopes, and whales. Our results show that increasing facial gracility with size is common, but not necessarily as ubiquitous as previously suggested. To address the mechanistic basis for this variation, we then review cranial adaptations for harder biting. These dictate that a more gracile cranium in larger species must represent a structural sacrifice in the ability to produce or withstand harder bites, relative to size. This leads us to propose that facial gracilisation in larger species is often a product of bite force allometry and phylogenetic niche conservatism, where more closely related species tend to exhibit more similar feeding ecology and biting behaviours and, therefore, absolute (size-independent) bite force requirements. Since larger species can produce the same absolute bite forces as smaller species with less effort, we propose that relaxed bite force demands can permit facial gracility in response to bone optimisation and alternative selection pressures. Thus, mammalian facial scaling represents an adaptive by-product of the shifting importance of selective pressures occurring with increased size. A reverse pattern of facial 'shortening' can accordingly also be found, and is retrieved in several cases here, where larger species incorporate novel feeding behaviours involving greater bite forces. We discuss multiple exceptions to a bite force-mediated influence on facial proportions across mammals which lead us to argue that ecomorphological specialisation of the cranium is likely to be the primary driver of facial scaling patterns, with some developmental constraints as possible secondary factors. A potential for larger species to have a wider range of cranial functions when less constrained by bite force demands might also explain why selection for larger sizes seems to be prevalent in some mammalian clades. The interplay between adaptation and constraint across size ranges thus presents an interesting consideration for a mechanistically grounded investigation of mammalian cranial allometry.
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Affiliation(s)
- D Rex Mitchell
- College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide, South Australia, 5001, Australia
- Australian Research Council Centre of Excellence for Australian Biodiversity and Heritage, Wollongong, New South Wales, 2522, Australia
| | - Emma Sherratt
- School of Biological Sciences, The University of Adelaide, Adelaide, South Australia, 5005, Australia
- South Australian Museum, Adelaide, South Australia, 5000, Australia
| | - Vera Weisbecker
- College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide, South Australia, 5001, Australia
- Australian Research Council Centre of Excellence for Australian Biodiversity and Heritage, Wollongong, New South Wales, 2522, Australia
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4
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Mitchell DR, Potter S, Eldridge MDB, Martin M, Weisbecker V. Functionally mediated cranial allometry evidenced in a genus of rock-wallabies. Biol Lett 2024; 20:20240045. [PMID: 38531413 PMCID: PMC10965333 DOI: 10.1098/rsbl.2024.0045] [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: 01/26/2024] [Accepted: 03/04/2024] [Indexed: 03/28/2024] Open
Abstract
In assessments of skeletal variation, allometry (disproportionate change of shape with size) is often corrected to examine size-independent variation for hypotheses relating to function. However, size-related trade-offs in functional demands may themselves be an underestimated driver of mammalian cranial diversity. Here, we use geometric morphometrics alongside dental measurements to assess craniodental allometry in the rock-wallaby genus Petrogale (all 17 species, 370 individuals). We identified functional aspects of evolutionary allometry that can be both extensions of, and correlated negatively with, static or ontogenetic allometric patterns. Regarding constraints, larger species tended to have relatively smaller braincases and more posterior orbits, the former of which might represent a constraint on jaw muscle anatomy. However, they also tended to have more anterior dentition and smaller posterior zygomatic arches, both of which support the hypothesis of relaxed bite force demands and accommodation of different selective pressures that favour facial elongation. By contrast, two dwarf species had stouter crania with divergent dental adaptations that together suggest increased relative bite force capacity. This likely allows them to feed on forage that is mechanically similar to that consumed by larger relatives. Our results highlight a need for nuanced considerations of allometric patterns in future research of mammalian cranial diversity.
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Affiliation(s)
- D. Rex Mitchell
- College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide, South Australia 5001, Australia
- Australian Research Council Centre of Excellence for Australian Biodiversity and Heritage, Wollongong, New South Wales 2522, Australia
| | - Sally Potter
- School of Natural Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
- Australian Museum Research Institute, Sydney, New South Wales 2010, Australia
| | - Mark D. B. Eldridge
- Australian Museum Research Institute, Sydney, New South Wales 2010, Australia
| | - Meg Martin
- College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide, South Australia 5001, Australia
| | - Vera Weisbecker
- College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide, South Australia 5001, Australia
- Australian Research Council Centre of Excellence for Australian Biodiversity and Heritage, Wollongong, New South Wales 2522, Australia
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5
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Law CJ, Hlusko LJ, Tseng ZJ. Uncovering the mosaic evolution of the carnivoran skeletal system. Biol Lett 2024; 20:20230526. [PMID: 38263882 PMCID: PMC10806395 DOI: 10.1098/rsbl.2023.0526] [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: 11/09/2023] [Accepted: 12/21/2023] [Indexed: 01/25/2024] Open
Abstract
The diversity of vertebrate skeletons is often attributed to adaptations to distinct ecological factors such as diet, locomotion, and sensory environment. Although the adaptive evolution of skull, appendicular skeleton, and vertebral column is well studied in vertebrates, comprehensive investigations of all skeletal components simultaneously are rarely performed. Consequently, we know little of how modes of evolution differ among skeletal components. Here, we tested if ecological and phylogenetic effects led to distinct modes of evolution among the cranial, appendicular and vertebral regions in extant carnivoran skeletons. Using multivariate evolutionary models, we found mosaic evolution in which only the mandible, hindlimb and posterior (i.e. last thoracic and lumbar) vertebrae showed evidence of adaptation towards ecological regimes whereas the remaining skeletal components reflect clade-specific evolutionary shifts. We hypothesize that the decoupled evolution of individual skeletal components may have led to the origination of distinct adaptive zones and morphologies among extant carnivoran families that reflect phylogenetic hierarchies. Overall, our work highlights the importance of examining multiple skeletal components simultaneously in ecomorphological analyses. Ongoing work integrating the fossil and palaeoenvironmental record will further clarify deep-time drivers that govern the carnivoran diversity we see today and reveal the complexity of evolutionary processes in multicomponent systems.
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Affiliation(s)
- Chris J. Law
- Department of Integrative Biology, University of Texas, Austin, TX, USA
- Burke Museum and Department of Biology, University of Washington, Seattle, WA, USA
- Department of Integrative Biology, University of California, Berkeley, CA, USA
| | - Leslea J. Hlusko
- National Research Center on Human Evolution (CENIEH), Burgos, Spain
| | - Z. Jack Tseng
- Department of Integrative Biology, University of California, Berkeley, CA, USA
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6
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Tan A, St. John M, Chau D, Clair C, Chan H, Holzman R, Martin CH. Multiple performance peaks for scale-biting in an adaptive radiation of pupfishes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.22.573139. [PMID: 38187684 PMCID: PMC10769438 DOI: 10.1101/2023.12.22.573139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
The physical interactions between organisms and their environment ultimately shape their rate of speciation and adaptive radiation, but the contributions of biomechanics to evolutionary divergence are frequently overlooked. Here we investigated an adaptive radiation of Cyprinodon pupfishes to measure the relationship between feeding kinematics and performance during adaptation to a novel trophic niche, lepidophagy, in which a predator removes only the scales, mucus, and sometimes tissue from their prey using scraping and biting attacks. We used high-speed video to film scale-biting strikes on gelatin cubes by scale-eater, molluscivore, generalist, and hybrid pupfishes and subsequently measured the dimensions of each bite. We then trained the SLEAP machine-learning animal tracking model to measure kinematic landmarks and automatically scored over 100,000 frames from 227 recorded strikes. Scale-eaters exhibited increased peak gape and greater bite length; however, substantial within-individual kinematic variation resulted in poor discrimination of strikes by species or strike type. Nonetheless, a complex performance landscape with two distinct peaks best predicted gel-biting performance, corresponding to a significant nonlinear interaction between peak gape and peak jaw protrusion in which scale-eaters and their hybrids occupied a second performance peak requiring larger peak gape and greater jaw protrusion. A bite performance valley separating scale-eaters from other species may have contributed to their rapid evolution and is consistent with multiple estimates of a multi-peak fitness landscape in the wild. We thus present an efficient deep-learning automated pipeline for kinematic analyses of feeding strikes and a new biomechanical model for understanding the performance and rapid evolution of a rare trophic niche.
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Affiliation(s)
- Anson Tan
- Department of Integrative Biology, University of California, Berkeley
- Museum of Vertebrate Zoology, University of California, Berkeley
| | | | - Dylan Chau
- Department of Integrative Biology, University of California, Berkeley
- Museum of Vertebrate Zoology, University of California, Berkeley
| | - Chloe Clair
- Department of Integrative Biology, University of California, Berkeley
- Museum of Vertebrate Zoology, University of California, Berkeley
| | | | - Roi Holzman
- School of Zoology, Tel Aviv University, Eilat, Israel
- Inter-University Institute for Marine Sciences, Eilat, Israel
| | - Christopher H. Martin
- Department of Integrative Biology, University of California, Berkeley
- Museum of Vertebrate Zoology, University of California, Berkeley
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7
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Tseng ZJ, Garcia-Lara S, Flynn JJ, Holmes E, Rowe TB, Dickson BV. A switch in jaw form-function coupling during the evolution of mammals. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220091. [PMID: 37183899 PMCID: PMC10184249 DOI: 10.1098/rstb.2022.0091] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023] Open
Abstract
The evolutionary shift from a single-element ear, multi-element jaw to a multi-element ear, single-element jaw during the transition to crown mammals marks one of the most dramatic structural transformations in vertebrates. Research on this transformation has focused on mammalian middle-ear evolution, but a mandible comprising only the dentary is equally emblematic of this evolutionary radiation. Here, we show that the remarkably diverse jaw shapes of crown mammals are coupled with surprisingly stereotyped jaw stiffness. This strength-based morphofunctional regime has a genetic basis and allowed mammalian jaws to effectively resist deformation as they radiated into highly disparate forms with markedly distinct diets. The main functional consequences for the mandible of decoupling hearing and mastication were a trade-off between higher jaw stiffness versus decreased mechanical efficiency and speed compared with non-mammals. This fundamental and consequential shift in jaw form-function underpins the ecological and taxonomic diversification of crown mammals. This article is part of the theme issue 'The mammalian skull: development, structure and function'.
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Affiliation(s)
- Z Jack Tseng
- Department of Integrative Biology, University of California, Berkeley, CA 94720, USA
- Museum of Paleontology, University of California, Berkeley, CA 94720, USA
- Division of Paleontology, American Museum of Natural History, New York, NY 10024, USA
| | - Sergio Garcia-Lara
- Department of Integrative Biology, University of California, Berkeley, CA 94720, USA
- Museum of Paleontology, University of California, Berkeley, CA 94720, USA
| | - John J Flynn
- Division of Paleontology, American Museum of Natural History, New York, NY 10024, USA
- Richard Gilder Graduate School, American Museum of Natural History, New York, NY 10024, USA
| | - Emily Holmes
- Department of Integrative Biology, University of California, Berkeley, CA 94720, USA
| | - Timothy B Rowe
- Jackson School of Geological Sciences, University of Texas, Austin, TX 78712, USA
| | - Blake V Dickson
- Department of Evolutionary Anthropology, Duke University, Durham, NC 27708, USA
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8
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Waldman E, Gonzalez Y, Flynn JJ, Tseng ZJ. Dental topographic proxies for ecological characteristics in carnivoran mammals. J Anat 2023; 242:627-641. [PMID: 36690466 PMCID: PMC10008270 DOI: 10.1111/joa.13806] [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: 06/08/2022] [Revised: 10/27/2022] [Accepted: 11/29/2022] [Indexed: 01/25/2023] Open
Abstract
Form-function relationships in mammalian feeding systems are active topics of research in evolutionary biology. This is due principally to their fundamental importance for understanding dietary adaptations in extinct taxa and macro-evolutionary patterns of morphological transformations through changing environments. We hypothesize that three-dimensional dental topographic metrics represent stronger predictors for dietary and other ecological variables than do linear measurements. To test this hypothesis, we measured three dental topographic metrics: Relief Index (RFI), Dirichlet Normal Energy (DNE), and Orientation Patch Count Rotated (OPCR) in 57 extant carnivoran species. Premolar and molar dental topographic indices were regressed against activity, diet breadth, habitat breadth, terrestriality, and trophic level variables within a phylogenetic framework. The results of this study showed significant correlations between RFI and the ecological variables diet breadth and trophic level. Weaker correlations are documented between OPCR and activity and between DNE and trophic level. Our results suggest that cusp height is strongly reflective of dietary ecology in carnivorans as a whole, and represents a proxy mainly for different degrees of hypercarnivory observed within this group of predatory mammals.
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Affiliation(s)
- Emily Waldman
- University at Buffalo School of Dental Medicine, Buffalo, New York, USA
| | - Yoly Gonzalez
- Department of Oral Diagnostic Sciences, University at Buffalo, School of Dental Medicine, Buffalo, New York, USA
| | - John J Flynn
- Division of Paleontology, American Museum of Natural History, New York, New York, USA
| | - Z Jack Tseng
- Division of Paleontology, American Museum of Natural History, New York, New York, USA.,Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, California, USA
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9
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Button DJ, Porro LB, Lautenschlager S, Jones MEH, Barrett PM. Multiple pathways to herbivory underpinned deep divergences in ornithischian evolution. Curr Biol 2023; 33:557-565.e7. [PMID: 36603586 DOI: 10.1016/j.cub.2022.12.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 09/28/2022] [Accepted: 12/08/2022] [Indexed: 01/06/2023]
Abstract
The extent to which evolution is deterministic is a key question in biology,1,2,3,4,5,6,7,8,9 with intensive debate on how adaptation6,10,11,12,13 and constraints14,15,16 might canalize solutions to ecological challenges.4,5,6 Alternatively, unique adaptations1,9,17 and phylogenetic contingency1,3,18 may render evolution fundamentally unpredictable.3 Information from the fossil record is critical to this debate,1,2,11 but performance data for extinct taxa are limited.7 This knowledge gap is significant, as general morphology may be a poor predictor of biomechanical performance.17,19,20 High-fiber herbivory originated multiple times within ornithischian dinosaurs,21 making them an ideal clade for investigating evolutionary responses to similar ecological pressures.22 However, previous biomechanical modeling studies on ornithischian crania17,23,24,25 have not compared early-diverging taxa spanning independent acquisitions of herbivory. Here, we perform finite-element analysis on the skull of five early-diverging members of the major ornithischian clades to characterize morphofunctional pathways to herbivory. Results reveal limited functional convergence among ornithischian clades, with each instead achieving comparable performance, in terms of reconstructed patterns and magnitudes of functionally induced stress, through different adaptations of the feeding apparatus. Thyreophorans compensated for plesiomorphic low performance through increased absolute size, heterodontosaurids expanded jaw adductor muscle volume, ornithopods increased jaw system efficiency, and ceratopsians combined these approaches. These distinct solutions to the challenges of herbivory within Ornithischia underpinned the success of this diverse clade. Furthermore, the resolution of multiple solutions to equivalent problems within a single clade through macroevolutionary time demonstrates that phenotypic evolution is not necessarily predictable, instead arising from the interplay of adaptation, innovation, contingency, and constraints.1,2,3,7,8,9,18.
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Affiliation(s)
- David J Button
- Science Group, The Natural History Museum, Cromwell Road, London SW7 5BD, UK.
| | - Laura B Porro
- Centre for Integrative Anatomy, Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6DE, UK
| | - Stephan Lautenschlager
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Marc E H Jones
- Science Group, The Natural History Museum, Cromwell Road, London SW7 5BD, UK
| | - Paul M Barrett
- Science Group, The Natural History Museum, Cromwell Road, London SW7 5BD, UK
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10
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Tseng ZJ. Evolution: Mix-and-match adaptations in plant-eating dinosaurs. Curr Biol 2023; 33:R103-R106. [PMID: 36750019 DOI: 10.1016/j.cub.2022.12.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Ornithischian dinosaurs were primary consumers in Mesozoic ecosystems, their evolution intricately linked to challenges of a plant-heavy diet. Whether phenotypic similarities among different ornithischian lineages imply a common functional solution to herbivory is unclear. New research suggests that they evolved herbivory via multiple biomechanical pathways.
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Affiliation(s)
- Z Jack Tseng
- Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, CA 94720, USA.
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11
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Law CJ, Blackwell EA, Curtis AA, Dickinson E, Hartstone-Rose A, Santana SE. Decoupled evolution of the cranium and mandible in carnivoran mammals. Evolution 2022; 76:2959-2974. [PMID: 35875871 DOI: 10.1111/evo.14578] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 06/06/2022] [Accepted: 06/17/2022] [Indexed: 01/22/2023]
Abstract
The relationship between skull morphology and diet is a prime example of adaptive evolution. In mammals, the skull consists of the cranium and the mandible. Although the mandible is expected to evolve more directly in response to dietary changes, dietary regimes may have less influence on the cranium because additional sensory and brain-protection functions may impose constraints on its morphological evolution. Here, we tested this hypothesis by comparing the evolutionary patterns of cranium and mandible shape and size across 100+ species of carnivoran mammals with distinct feeding ecologies. Our results show decoupled modes of evolution in cranial and mandibular shape; cranial shape follows clade-based evolutionary shifts, whereas mandibular shape evolution is linked to broad dietary regimes. These results are consistent with previous hypotheses regarding hierarchical morphological evolution in carnivorans and greater evolutionary lability of the mandible with respect to diet. Furthermore, in hypercarnivores, the evolution of both cranial and mandibular size is associated with relative prey size. This demonstrates that dietary diversity can be loosely structured by craniomandibular size within some guilds. Our results suggest that mammal skull morphological evolution is shaped by mechanisms beyond dietary adaptation alone.
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Affiliation(s)
- Chris J Law
- Department of Integrative Biology, University of Texas, Austin, Texas, 78712.,Department of Biology, University of Washington, Seattle, Washington, 98105.,Burke Museum of Natural History and Culture, University of Washington, Seattle, Washington, 98105.,Richard Gilder Graduate School, American Museum of Natural History, New York, New York, 10024.,Department of Mammalogy, American Museum of Natural History, New York, New York, 10024.,Division of Paleontology, American Museum of Natural History, New York, New York, 10024
| | - Emily A Blackwell
- Richard Gilder Graduate School, American Museum of Natural History, New York, New York, 10024.,Department of Mammalogy, American Museum of Natural History, New York, New York, 10024.,Division of Paleontology, American Museum of Natural History, New York, New York, 10024.,Department of Biological Sciences, Smith College, Northampton, Massachusetts, 01063
| | - Abigail A Curtis
- Department of Biology, University of Washington, Seattle, Washington, 98105.,Burke Museum of Natural History and Culture, University of Washington, Seattle, Washington, 98105
| | - Edwin Dickinson
- Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina, 27695.,Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, New York, New York, 11545
| | - Adam Hartstone-Rose
- Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina, 27695
| | - Sharlene E Santana
- Department of Biology, University of Washington, Seattle, Washington, 98105.,Burke Museum of Natural History and Culture, University of Washington, Seattle, Washington, 98105
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12
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Pollock TI, Panagiotopoulou O, Hocking DP, Evans AR. Taking a stab at modelling canine tooth biomechanics in mammalian carnivores with beam theory and finite-element analysis. ROYAL SOCIETY OPEN SCIENCE 2022; 9:220701. [PMID: 36300139 PMCID: PMC9579775 DOI: 10.1098/rsos.220701] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 09/30/2022] [Indexed: 06/16/2023]
Abstract
Canine teeth are vital to carnivore feeding ecology, facilitating behaviours related to prey capture and consumption. Forms vary with specific feeding ecologies; however, the biomechanics that drive these relationships have not been comprehensively investigated. Using a combination of beam theory analysis (BTA) and finite-element analysis (FEA) we assessed how aspects of canine shape impact tooth stress, relating this to feeding ecology. The degree of tooth lateral compression influenced tolerance of multidirectional loads, whereby canines with more circular cross-sections experienced similar maximum stresses under pulling and shaking loads, while more ellipsoid canines experienced higher stresses under shaking loads. Robusticity impacted a tooth's ability to tolerate stress and appears to be related to prey materials. Robust canines experience lower stresses and are found in carnivores regularly encountering hard foods. Slender canines experience higher stresses and are associated with carnivores biting into muscle and flesh. Curvature did not correlate with tooth stress; however, it did impact bending during biting. Our simulations help identify scenarios where canine forms are likely to break and pinpoint areas where this breakage may occur. These patterns demonstrate how canine shape relates to tolerating the stresses experienced when killing and feeding, revealing some of the form-function relationships that underpin mammalian carnivore ecologies.
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Affiliation(s)
- Tahlia I. Pollock
- School of Biological Sciences, Monash University, Clayton 3800, Australia
| | - Olga Panagiotopoulou
- Monash Biomedicine Discovery Institute, Department of Anatomy & Developmental Biology, Monash University, Clayton 3800, Australia
| | - David P. Hocking
- School of Biological Sciences, Monash University, Clayton 3800, Australia
- Zoology, Tasmanian Museum and Art Gallery, Hobart, Australia
| | - Alistair R. Evans
- School of Biological Sciences, Monash University, Clayton 3800, Australia
- Geosciences, Museums Victoria, Melbourne, Victoria, Australia
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13
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Russo LF, Meloro C, De Silvestri M, Chadwick EA, Loy A. Better sturdy or slender? Eurasian otter skull plasticity in response to feeding ecology. PLoS One 2022; 17:e0274893. [PMID: 36174011 PMCID: PMC9521905 DOI: 10.1371/journal.pone.0274893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 09/06/2022] [Indexed: 11/18/2022] Open
Abstract
Otters are semi-aquatic mammals specialized in feeding on aquatic prey. The Eurasian otter Lutra lutra is the most widely distributed otter species. Despite a low degree of genetic variation across its European range, the population from Great Britain exhibits distinct genetic structuring. We examined 43 skulls of adult Eurasian otters belonging to 18 sampling localities and three genetic clusters (Shetlands, Wales and Scotland). For each sample location, information regarding climate was described using bioclimatic variables from WorldClim, and information on otter diet was extracted from the literature. By using photogrammetry, 3D models were obtained for each skull. To explore any evidence of adaptive divergence within these areas we used a three dimensional geometric morphometric approach to test differences in skull size and shape between areas with genetically distinct populations, as well as the influence of diet, isolation by distance and climate. Males were significantly larger in skull size than females across all the three genetic clusters. Skull shape, but not size, appeared to differ significantly among genetic clusters, with otters from Shetland exhibiting wider zygomatic arches and longer snouts compared to otters from Wales, whereas otters from Scotland displayed intermediate traits. A significant relationship could also be found between skull shape variation, diet as well as climate. Specifically, otters feeding on freshwater fish had more slender and short-snouted skulls compared to otters feeding mostly on marine fish. Individuals living along the coast are characterised by a mixed feeding regime based on marine fish and crustaceans and their skull showed an intermediate shape. Coastal and island otters also had larger orbits and eyes more oriented toward the ground, a larger nasal cavity, and a larger distance between postorbital processes and zygomatic arch. These functional traits could also represent an adaptation to favour the duration and depth of diving, while the slender skull of freshwater feeding otters could improve the hydrodynamics.
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Affiliation(s)
- Luca Francesco Russo
- EnvixLab, Department of Biosciences and Territory, Università degli Studi del Molise, Pesche, Italy
| | - Carlo Meloro
- Research Centre in Evolutionary Anthropology and Palaeoecology, Liverpool John Moores University, Liverpool, United Kingdom
- * E-mail:
| | - Mara De Silvestri
- EnvixLab, Department of Biosciences and Territory, Università degli Studi del Molise, Pesche, Italy
| | - Elizabeth A. Chadwick
- Cardiff University, Biomedical Science Building, Museum Avenue, Cardiff, United Kingdom
| | - Anna Loy
- EnvixLab, Department of Biosciences and Territory, Università degli Studi del Molise, Pesche, Italy
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14
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Mandible shape variation and feeding biomechanics in minks. Sci Rep 2022; 12:4997. [PMID: 35322070 PMCID: PMC8943020 DOI: 10.1038/s41598-022-08754-4] [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: 12/03/2021] [Accepted: 03/10/2022] [Indexed: 11/08/2022] Open
Abstract
European and American minks are very similar in ecology, behavior and morphology. Both species hunt terrestrial vertebrates and aquatic prey, but the American mink is a more generalist predator which, among other factors, allows it to outcompete the European mink in areas where it has been introduced. We used 3D geometric morphometrics and estimates of muscle mechanical advantage to assess the degree of variation in mandibular morphology, and to determine whether such variation reflects dietary differences between the two species. The three main axes of variation represented interspecific differences, a common allometric trajectory between species and sexes, and the interspecific effect of sexual size dimorphism, with males having overall stronger bites than females. Differences in mandible shape and biomechanical parameters suggest that American minks are better equipped for preying on terrestrial vertebrates, while the features seen in European mink could be related to tougher prey, fish capture, or both. Additionally, within each species, the larger specimens of each sex present indicators of a higher percentage of terrestrial prey in their diet. These results indicate a low potential dietary overlap between both species, suggesting that factors other than prey competition may have a role in the decline of the European mink.
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15
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Law CJ. Different evolutionary pathways lead to incomplete convergence of elongate body shapes in carnivoran mammals. Syst Biol 2021; 71:788-796. [PMID: 34791502 DOI: 10.1093/sysbio/syab091] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 11/01/2021] [Accepted: 11/09/2021] [Indexed: 11/13/2022] Open
Abstract
Although convergence is often recognized as a ubiquitous feature across the Tree of Life, whether the underlying traits also exhibit similar evolutionary pathways towards convergent forms puzzles biologists. In carnivoran mammals, "elongate," "slender," and "long" are often used to describe and even to categorize mustelids (martens, polecats, and weasels), herpestids (mongooses), viverrids (civets and genets), and other carnivorans together. But just how similar these carnivorans are and whether there is convergence in the morphological component that contribute to elongation has never been assessed. Here, I found that these qualitatively-described elongate carnivorans exhibited incomplete convergence towards elongate bodies compared to other terrestrial carnivorans. In contrast, the morphological components underlying body shape variation do not exhibit convergence despite evidence that these components are more elongate in elongate carnivorans compared to non-elongate carnivorans. Furthermore, these components also exhibited shorter but different phylogenetic half-lives towards more elongate adaptive peaks, indicating that different selective pressures can create multiple pathways to elongation. Incorporating the fossil record will facilitate further investigation of whether body elongation evolved adaptively or if it is simply a retained ancestral trait.
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Affiliation(s)
- Chris J Law
- Department of Biology, University of Washington, Seattle, WA, 98105; Richard Gilder Graduate School, Department of Mammalogy, and Division of Paleontology, American Museum of Natural History, New York, NY, USA 10024
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16
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Schwartz MK, Walters AD, Pilgrim KL, Moriarty KM, Slauson KM, Zielinski WJ, Aubry KB, Sacks BN, Zarn KE, Quinn CB, Young MK. Pliocene-Early Pleistocene Geological Events Structure Pacific Martens (Martes caurina). J Hered 2021; 111:169-181. [PMID: 32161974 DOI: 10.1093/jhered/esaa005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Accepted: 02/10/2020] [Indexed: 11/15/2022] Open
Abstract
The complex topography, climate, and geological history of Western North America have shaped contemporary patterns of biodiversity and species distributions in the region. Pacific martens (Martes caurina) are distributed along the northern Pacific Coast of North America with disjunct populations found throughout the Northwestern Forested Mountains and Marine West Coast Forest ecoregions of the West Coast. Martes in this region have been classified into subspecies; however, the subspecific designation has been extensively debated. In this study, we use genomic data to delineate conservation units of Pacific marten in the Sierra-Cascade-Coastal montane belt in the western United States. We analyzed the mitochondrial genome for 94 individuals to evaluate the spatial distribution and divergence times of major lineages. We further genotyped 401 individuals at 13 microsatellite loci to investigate major patterns of population structure. Both nuclear and mitochondrial DNA suggest substantial genetic substructure concordant with historical subspecies designations. Our results revealed that the region contains 2 distinct mitochondrial lineages: a Cascades/Sierra lineage that diverged from the Cascades/coastal lineage 2.23 (1.48-3.14 mya), consistent with orogeny of the Cascade Mountain chain. Interestingly, Pacific Martes share phylogeographic patterns similar with other sympatric taxa, suggesting that the complex geological history has shaped the biota of this region. The information is critical for conservation and management efforts, and further investigation of adaptive diversity is warranted following appropriate revision of conservation management designations.
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Affiliation(s)
- Michael K Schwartz
- USDA Forest Service, National Genomics Center for Wildlife and Fish Conservation, Missoula, MT
| | - Ashley D Walters
- USDA Forest Service, National Genomics Center for Wildlife and Fish Conservation, Missoula, MT
| | - Kristine L Pilgrim
- USDA Forest Service, National Genomics Center for Wildlife and Fish Conservation, Missoula, MT
| | - Katie M Moriarty
- National Council for Air and Stream Improvement, Inc., Corvallis, OR
| | - Keith M Slauson
- USDA Forest Service, Pacific Southwest Research Station, Arcata, CA
| | - William J Zielinski
- USDA Forest Service, National Genomics Center for Wildlife and Fish Conservation, Missoula, MT.,USDA Forest Service, Pacific Southwest Research Station, Arcata, CA
| | - Keith B Aubry
- USDA Forest Service, Pacific Northwest Research Station, Olympia, WA
| | - Benjamin N Sacks
- Mammalian Ecology and Conservation Unit, Veterinary Genetics Laboratory, University of California, Davis, Davis, CA
| | - Katherine E Zarn
- USDA Forest Service, National Genomics Center for Wildlife and Fish Conservation, Missoula, MT
| | - Cate B Quinn
- Mammalian Ecology and Conservation Unit, Veterinary Genetics Laboratory, University of California, Davis, Davis, CA
| | - Michael K Young
- USDA Forest Service, National Genomics Center for Wildlife and Fish Conservation, Missoula, MT
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17
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Brassard C, Merlin M, Monchâtre-Leroy E, Guintard C, Barrat J, Garès H, Larralle A, Triquet R, Houssin C, Callou C, Cornette R, Herrel A. Masticatory system integration in a commensal canid: interrelationships between bones, muscles and bite force in the red fox. J Exp Biol 2021; 224:jeb.224394. [DOI: 10.1242/jeb.224394] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 01/28/2021] [Indexed: 12/20/2022]
Abstract
ABSTRACT
The jaw system in canids is essential for defence and prey acquisition. However, how it varies in wild species in comparison with domestic species remains poorly understood, yet is of interest in terms of understanding the impact of artificial selection. Here, we explored the variability and interrelationships between the upper and lower jaws, muscle architecture and bite force in the red fox (Vulpes vulpes). We performed dissections and used 3D geometric morphometric approaches to quantify jaw shape in 68 foxes. We used a static lever model and bite force estimates were compared with in vivo measurements of 10 silver foxes. Our results show strong relationships exist between cranial and mandible shape, and between cranial or mandible shape on the one hand and muscles or estimated bite force on the other hand, confirming the strong integration of the bony and muscular components of the jaw system. These strong relationships are strongly driven by size. The functional links between shape and estimated bite force are stronger for the mandible, which probably reflects its greater specialisation towards biting. We then compared our results with data previously obtained for dogs (Canis lupus familiaris) to investigate the effect of domestication. Foxes and dogs differ in skull shape and muscle physiological cross-sectional area (PCSA). They show a similar amount of morphological variation in muscle PCSA, but foxes show lower variation in cranial and mandible shape. Interestingly, the patterns of covariation are not stronger in foxes than in dogs, suggesting that domestication did not lead to a disruption of the functional links of the jaw system.
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Affiliation(s)
- Colline Brassard
- Mécanismes Adaptatifs et Evolution (MECADEV), Muséum national d'Histoire naturelle, CNRS, 55 rue Buffon 75005, Paris, France
- Archéozoologie, archéobotanique: sociétés, pratiques et environnements (AASPE), Muséum national d'Histoire naturelle, CNRS, CP55, 57 rue Cuvier, 75005 Paris, France
| | - Marilaine Merlin
- Mécanismes Adaptatifs et Evolution (MECADEV), Muséum national d'Histoire naturelle, CNRS, 55 rue Buffon 75005, Paris, France
| | - Elodie Monchâtre-Leroy
- ANSES, Laboratoire de la rage et de la faune sauvage, Station expérimentale d'Atton, CS 40009, 54220 Malzéville, France
| | - Claude Guintard
- Laboratoire d'Anatomie comparée, Ecole Nationale Vétérinaire, de l'Agroalimentaire et de l'Alimentation, Nantes Atlantique – ONIRIS, Nantes Cedex 03, France
- GEROM, UPRES EA 4658, LABCOM ANR NEXTBONE, Faculté de santé de l'Université d'Angers, 49933 Angers Cedex, France
| | - Jacques Barrat
- ANSES, Laboratoire de la rage et de la faune sauvage, Station expérimentale d'Atton, CS 40009, 54220 Malzéville, France
| | - Hélène Garès
- Direction des Services Vétérinaires – D.D.C.S.P.P. de la Dordogne, 24000 Périgueux, France
| | | | - Raymond Triquet
- Université de Lille III, Domaine Universitaire du Pont de Bois BP 60149, Villeneuve d'ascq Cedex 59653, France
| | - Céline Houssin
- Institut de Systématique, Evolution, Biodiversité (ISYEB), CNRS, Muséum national d'Histoire naturelle, Sorbonne Université, Ecole Pratique des hautes Etudes, Université des Antilles, CNRS, CP 50, 57 rue Cuvier, 75005 Paris, France
| | - Cécile Callou
- Mécanismes Adaptatifs et Evolution (MECADEV), Muséum national d'Histoire naturelle, CNRS, 55 rue Buffon 75005, Paris, France
| | - Raphaël Cornette
- Institut de Systématique, Evolution, Biodiversité (ISYEB), CNRS, Muséum national d'Histoire naturelle, Sorbonne Université, Ecole Pratique des hautes Etudes, Université des Antilles, CNRS, CP 50, 57 rue Cuvier, 75005 Paris, France
| | - Anthony Herrel
- Mécanismes Adaptatifs et Evolution (MECADEV), Muséum national d'Histoire naturelle, CNRS, 55 rue Buffon 75005, Paris, France
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18
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Allen VR, Kilbourne BM, Hutchinson JR. The evolution of pelvic limb muscle moment arms in bird-line archosaurs. SCIENCE ADVANCES 2021; 7:7/12/eabe2778. [PMID: 33741593 PMCID: PMC7978429 DOI: 10.1126/sciadv.abe2778] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 02/03/2021] [Indexed: 06/07/2023]
Abstract
Bipedal locomotion evolved along the archosaurian lineage to birds, shifting from "hip-based" to "knee-based" mechanisms. However, the roles of individual muscles in these changes and their evolutionary timings remain obscure. Using 13 three-dimensional musculoskeletal models of the hindlimbs of bird-line archosaurs, we quantify how the moment arms (i.e., leverages) of 35 locomotor muscles evolved. Our results support two hypotheses: From early theropod dinosaurs to birds, knee flexors' moment arms decreased relative to knee extensors', and medial long-axis rotator moment arms for the hip increased (trading off with decreased hip abductor moment arms). Our results reveal how, from the Triassic Period, bipedal theropod dinosaurs gradually modified their hindlimb form and function, shifting more from hip-based to knee-based locomotion and hip-abductor to hip-rotator balancing mechanisms inherited by birds. Yet, we also discover unexpected ancestral specializations in larger Jurassic theropods, lost later in the bird-line, complicating the paradigm of gradual transformation.
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Affiliation(s)
- V R Allen
- Structure and Motion Laboratory, Department of Comparative Biomedical Sciences, The Royal Veterinary College, Hawkshead Lane, North Mymms, Hertfordshire AL9 7TA, UK
| | - B M Kilbourne
- Museum für Naturkunde Berlin, Leibniz Institut für Evolutions-und Biodiversitätsforschung, Invalidenstraße 43, 10115 Berlin, Germany
| | - J R Hutchinson
- Structure and Motion Laboratory, Department of Comparative Biomedical Sciences, The Royal Veterinary College, Hawkshead Lane, North Mymms, Hertfordshire AL9 7TA, UK.
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19
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20
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Lautenschlager S, Figueirido B, Cashmore DD, Bendel EM, Stubbs TL. Morphological convergence obscures functional diversity in sabre-toothed carnivores. Proc Biol Sci 2020; 287:20201818. [PMID: 32993469 PMCID: PMC7542828 DOI: 10.1098/rspb.2020.1818] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 09/08/2020] [Indexed: 11/12/2022] Open
Abstract
The acquisition of elongated, sabre-like canines in multiple vertebrate clades during the last 265 Myr represents a remarkable example for convergent evolution. Due to striking superficial similarities in the cranial skeleton, the same or similar skull and jaw functions have been inferred for sabre-toothed species and interpreted as an adaptation to subdue large-bodied prey. However, although some sabre-tooth lineages have been classified into different ecomorphs (dirk-tooths and scimitar-tooths) the functional diversity within and between groups and the evolutionary paths leading to these specializations are unknown. Here, we use a suite of biomechanical simulations to analyse key functional parameters (mandibular gape angle, bending strength, bite force) to compare the functional performance of different groups and to quantify evolutionary rates across sabre-tooth vertebrates. Our results demonstrate a remarkably high functional diversity between sabre-tooth lineages and that different cranial function and prey killing strategies evolved within clades. Moreover, different biomechanical adaptations in coexisting sabre-tooth species further suggest that this functional diversity was at least partially driven by niche partitioning.
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Affiliation(s)
- Stephan Lautenschlager
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Borja Figueirido
- Departamento de Ecología y Geología, Facultad de Ciencias, Universidad de Málaga, 29071 Málaga, Spain
| | - Daniel D. Cashmore
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Eva-Maria Bendel
- Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Invalidenstraße 43, 10115 Berlin, Germany
- Institut für Biologie, Humboldt-Universität zu Berlin, Invalidenstraße 42, 10115 Berlin, Germany
| | - Thomas L. Stubbs
- School of Earth Sciences, University of Bristol, 24 Tyndall Avenue, Bristol BS8 1TQ, UK
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21
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Law CJ. Sex-specific ontogenetic patterns of cranial morphology, theoretical bite force, and underlying jaw musculature in fishers and American martens. J Anat 2020; 237:727-740. [PMID: 32519772 DOI: 10.1111/joa.13231] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 04/09/2020] [Accepted: 05/11/2020] [Indexed: 11/30/2022] Open
Abstract
The carnivoran cranium undergoes tremendous growth in size and development of shape to process prey as adults and, importantly, these ontogenetic processes can also differ between the sexes. How these ontogenetic changes in morphology actually relate to the underlying jaw musculature and overall bite performance has rarely been investigated. In this study, I examined sex-specific ontogenetic changes in cranial morphology, jaw adductor muscles, and theoretical bite force between subadults and adults in the fisher (Pekania pennanti) and American marten (Martes americana). I found evidence that cranial size alone does not completely explain ontogenetic increases in bite forces as found in other mammalian species. Instead, cranial shape development also drives ontogenetic increases in relative bite force by broadening the zygomatic arches and enlargement of the sagittal crest, both of which enable relatively larger jaw adductor muscles to attach. In contrast, examination of sexual dimorphism within each age-class revealed that cranial shape dimorphism did not translate to dimorphism in either size-corrected bite forces or size-corrected physiological cross-sectional area of the jaw adductor muscles. These results reveal that morphological size and shape variation can have different influences on bite performance depending on the level of intraspecific variation that is examined (i.e. ontogenetic versus sexual dimorphism).
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Affiliation(s)
- Chris J Law
- Department of Mammalogy and Division of Paleontology, American Museum of Natural History, New York, NY, USA
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22
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Clarifying relationships between cranial form and function in tapirs, with implications for the dietary ecology of early hominins. Sci Rep 2020; 10:8809. [PMID: 32483196 PMCID: PMC7264299 DOI: 10.1038/s41598-020-65586-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 04/20/2020] [Indexed: 11/11/2022] Open
Abstract
Paleontologists and paleoanthropologists have long debated relationships between cranial morphology and diet in a broad diversity of organisms. While the presence of larger temporalis muscle attachment area (via the presence of sagittal crests) in carnivorans is correlated with durophagy (i.e. hard-object feeding), many primates with similar morphologies consume an array of tough and hard foods—complicating dietary inferences of early hominins. We posit that tapirs, large herbivorous mammals showing variable sagittal crest development across species, are ideal models for examining correlations between textural properties of food and sagittal crest morphology. Here, we integrate dietary data, dental microwear texture analysis, and finite element analysis to clarify the functional significance of the sagittal crest in tapirs. Most notably, pronounced sagittal crests are negatively correlated with hard-object feeding in extant, and several extinct, tapirs and can actually increase stress and strain energy. Collectively, these data suggest that musculature associated with pronounced sagittal crests—and accompanied increases in muscle volume—assists with the processing of tough food items in tapirs and may yield similar benefits in other mammals including early hominins.
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23
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Pérez-Ramos A, Tseng ZJ, Grandal-D’Anglade A, Rabeder G, Pastor FJ, Figueirido B. Biomechanical simulations reveal a trade-off between adaptation to glacial climate and dietary niche versatility in European cave bears. SCIENCE ADVANCES 2020; 6:eaay9462. [PMID: 32270039 PMCID: PMC7112751 DOI: 10.1126/sciadv.aay9462] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 01/09/2020] [Indexed: 06/11/2023]
Abstract
The cave bear is one of the best known extinct large mammals that inhabited Europe during the "Ice Age," becoming extinct ≈24,000 years ago along with other members of the Pleistocene megafauna. Long-standing hypotheses speculate that many cave bears died during their long hibernation periods, which were necessary to overcome the severe and prolonged winters of the Last Glacial. Here, we investigate how long hibernation periods in cave bears would have directly affected their feeding biomechanics using CT-based biomechanical simulations of skulls of cave and extant bears. Our results demonstrate that although large paranasal sinuses were necessary for, and consistent with, long hibernation periods, trade-offs in sinus-associated cranial biomechanical traits restricted cave bears to feed exclusively on low energetic vegetal resources during the predormancy period. This biomechanical trade-off constitutes a new key factor to mechanistically explain the demise of this dominant Pleistocene megafaunal species as a direct consequence of climate cooling.
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Affiliation(s)
- Alejandro Pérez-Ramos
- Departamento de Ecología y Geología, Facultad de Ciencias, Universidad de Málaga, 29071 Málaga, Spain
| | - Z. Jack Tseng
- Department of Pathology and Anatomical Sciences, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14203, USA
| | | | - Gernot Rabeder
- University of Vienna, Institute of Palaeontology and Naturkundliche Station Lunz am See, Vienna, Austria
| | - Francisco J. Pastor
- Departamento de Anatomía y Radiología, Universidad de Valladolid, Valladolid 47005, Spain
| | - Borja Figueirido
- Departamento de Ecología y Geología, Facultad de Ciencias, Universidad de Málaga, 29071 Málaga, Spain
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24
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Gruntmejer K, Konietzko-Meier D, Marcé-Nogué J, Bodzioch A, Fortuny J. Cranial suture biomechanics in Metoposaurus krasiejowensis (Temnospondyli, Stereospondyli) from the upper Triassic of Poland. J Morphol 2019; 280:1850-1864. [PMID: 31638728 DOI: 10.1002/jmor.21070] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 09/16/2019] [Accepted: 10/04/2019] [Indexed: 11/08/2022]
Abstract
Cranial sutures connect adjacent bones of the skull and play an important role in the absorption of stresses that may occur during different activities. The Late Triassic temnospondyl amphibian Metoposaurus krasiejowensis has been extensively studied over the years in terms of skull biomechanics, but without a detailed description of the function of cranial sutures. In the present study, 34 thin sections of cranial sutures were examined in order to determine their histovariability and interpret their biomechanical role in the skull. The histological model was compared with three-dimensional-finite element analysis (FEA) simulations of the skull under bilateral and lateral biting as well as skull-raising loads for maximum and minimum principal stress. Histologically, only two sutural morphologies were recognised in the skull of Metoposaurus: interdigitated sutures (commonly associated with compressive stresses) are dominant along the entire length of the skull roof and palate; tongue-and-groove sutures (commonly associated with tensile stresses) are present across the maxilla. FEA shows a much more complex picture of stress type and distribution than predicted by sutures. Common to both methods is a predominance of compressive stresses which act on the skull during biting. The methods predict different stress regimes during biting in the posterior part of the skull: where histological analysis suggests compression, FEA predicts tension. For lateral biting and skull raising, histological and digital reconstructions show similar general patterns but with some variations.
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Affiliation(s)
- Kamil Gruntmejer
- Institute of Biology, Laboratory of Palaeobiology, University of Opole, Opole, Poland.,European Centre of Palaeontology, University of Opole, Opole, Poland
| | - Dorota Konietzko-Meier
- Institute of Biology, Laboratory of Palaeobiology, University of Opole, Opole, Poland.,Institute of Geoscience, University of Bonn, Bonn, Germany
| | - Jordi Marcé-Nogué
- Centrum für Naturkunde, University of Hamburg, Hamburg, Germany.,Institut Català de Paleontologia Miquel Crusafont, ICTA-ICP Building, Cerdanyola del Vallès, Spain
| | - Adam Bodzioch
- Institute of Biology, Laboratory of Palaeobiology, University of Opole, Opole, Poland
| | - Josep Fortuny
- Institut Català de Paleontologia Miquel Crusafont, ICTA-ICP Building, Cerdanyola del Vallès, Spain
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25
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Tsang LR, Wilson LAB, Ledogar J, Wroe S, Attard M, Sansalone G. Raptor talon shape and biomechanical performance are controlled by relative prey size but not by allometry. Sci Rep 2019; 9:7076. [PMID: 31068662 PMCID: PMC6506530 DOI: 10.1038/s41598-019-43654-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 04/24/2019] [Indexed: 11/30/2022] Open
Abstract
Most birds of prey (raptors), rely heavily on their talons for capturing prey. However, the relationship between talon shape and the ability to take prey is poorly understood. In this study we investigate whether raptor talons have evolved primarily in response to adaptive pressures exerted by different dietary demands, or if talon morphology is largely constrained by allometric or phylogenetic factors. We focus on the hallux talon and include 21 species in total varying greatly in body mass and feeding ecology, ranging from active predation on relatively large prey to obligate scavenging. To quantify the variation in talon shape and biomechanical performance within a phylogenetic framework, we combined three dimensional (3D) geometric morphometrics, finite element modelling and phylogenetic comparative methods. Our results indicate that relative prey size plays a key role in shaping the raptorial talon. Species that hunt larger prey are characterised by both distinct talon shape and mechanical performance when compared to species that predate smaller prey, even when accounting for phylogeny. In contrast to previous results of skull-based analysis, allometry had no significant effect. In conclusion, we found that raptor talon evolution has been strongly influenced by relative prey size, but not allometry and, that talon shape and mechanical performance are good indicators of feeding ecology.
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Affiliation(s)
- Leah R Tsang
- Ornithology Collection, Australian Museum Research Institute, Australian Museum, 1 William Street, Sydney, New South Wales, 2010, Australia.,Function, Evolution and Anatomy Research Laboratory, Zoology, School of Environmental and Rural Sciences, University of New England, Armidale, NSW, 2351, Australia
| | - Laura A B Wilson
- Palaeontology, Geobiology & Earth Archives Research Centre, School of Biological, Earth and Environmental Sciences. University of New South Wales, Sydney, NSW, 2052, Australia
| | - Justin Ledogar
- Function, Evolution and Anatomy Research Laboratory, Zoology, School of Environmental and Rural Sciences, University of New England, Armidale, NSW, 2351, Australia.,Department of Evolutionary Anthropology, Duke University, Durham, NC, 27708, USA
| | - Stephen Wroe
- Function, Evolution and Anatomy Research Laboratory, Zoology, School of Environmental and Rural Sciences, University of New England, Armidale, NSW, 2351, Australia
| | - Marie Attard
- Department of Animal and Plant Sciences, The University of Sheffield, Sheffield, S10 2TN, UK
| | - Gabriele Sansalone
- Function, Evolution and Anatomy Research Laboratory, Zoology, School of Environmental and Rural Sciences, University of New England, Armidale, NSW, 2351, Australia.
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Calamari ZT, Kuang-Hsien Hu J, Klein OD. Tissue Mechanical Forces and Evolutionary Developmental Changes Act Through Space and Time to Shape Tooth Morphology and Function. Bioessays 2018; 40:e1800140. [PMID: 30387177 PMCID: PMC6516060 DOI: 10.1002/bies.201800140] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 10/06/2018] [Indexed: 12/24/2022]
Abstract
Efforts from diverse disciplines, including evolutionary studies and biomechanical experiments, have yielded new insights into the genetic, signaling, and mechanical control of tooth formation and functions. Evidence from fossils and non-model organisms has revealed that a common set of genes underlie tooth-forming potential of epithelia, and changes in signaling environments subsequently result in specialized dentitions, maintenance of dental stem cells, and other phenotypic adaptations. In addition to chemical signaling, tissue forces generated through epithelial contraction, differential growth, and skeletal constraints act in parallel to shape the tooth throughout development. Here recent advances in understanding dental development from these studies are reviewed and important gaps that can be filled through continued application of evolutionary and biomechanical approaches are discussed.
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Affiliation(s)
- Zachary T. Calamari
- Department of Natural Sciences, Baruch College, City University of New York, New York City, New York, 10010, USA
- Department of Orofacial Sciences and Program in Craniofacial Biology, University of California, San Francisco, San Francisco, California, 94143, USA
| | - Jimmy Kuang-Hsien Hu
- Department of Orofacial Sciences and Program in Craniofacial Biology, University of California, San Francisco, San Francisco, California, 94143, USA
| | - Ophir D. Klein
- Department of Orofacial Sciences and Program in Craniofacial Biology, University of California, San Francisco, San Francisco, California, 94143, USA
- Department of Pediatrics and Institute for Human Genetics, University of California, San Francisco, San Francisco, California, 94143, USA
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27
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Colella JP, Johnson EJ, Cook JA. Reconciling molecules and morphology in North AmericanMartes. J Mammal 2018. [DOI: 10.1093/jmammal/gyy140] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Affiliation(s)
- Jocelyn P Colella
- Department of Biology and Museum of Southwestern Biology, University of New Mexico, Albuquerque, NM, USA
| | - Ellie J Johnson
- Department of Biology and Museum of Southwestern Biology, University of New Mexico, Albuquerque, NM, USA
| | - Joseph A Cook
- Department of Biology and Museum of Southwestern Biology, University of New Mexico, Albuquerque, NM, USA
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28
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Law CJ, Duran E, Hung N, Richards E, Santillan I, Mehta RS. Effects of diet on cranial morphology and biting ability in musteloid mammals. J Evol Biol 2018; 31:1918-1931. [DOI: 10.1111/jeb.13385] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 09/23/2018] [Accepted: 09/25/2018] [Indexed: 12/13/2022]
Affiliation(s)
- Chris J. Law
- Department of Ecology and Evolutionary Biology Coastal Biology Building University of California, Santa Cruz Santa Cruz CA USA
| | - Emma Duran
- Scotts Valley High School Scotts Valley CA USA
| | - Nancy Hung
- Massachusetts Institute of Technology Cambridge MA USA
| | - Ekai Richards
- Department of Ecology and Evolutionary Biology Coastal Biology Building University of California, Santa Cruz Santa Cruz CA USA
| | | | - Rita S. Mehta
- Department of Ecology and Evolutionary Biology Coastal Biology Building University of California, Santa Cruz Santa Cruz CA USA
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29
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Wysocki MA, Tseng ZJ. Allometry predicts trabecular bone structural properties in the carnivoran jaw joint. PLoS One 2018; 13:e0202824. [PMID: 30142221 PMCID: PMC6108490 DOI: 10.1371/journal.pone.0202824] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 08/09/2018] [Indexed: 11/18/2022] Open
Abstract
Because overall cranial morphology-biomechanics linkage in carnivorans is significantly influenced by both feeding and non-feeding ecological variables, whole-skull mechanical performance measures may be less sensitive to feeding ecology than regional characteristics within the skull. The temporomandibular joint could be one regional characteristic that is highly sensitive to feeding ecology considering that this joint is used in prey capture, food processing, and experiences compressive loading during mastication. Through 3D model construction, 3D printing, and compression tests, morphological and mechanical performance measures were determined for the temporomandibular joint trabecular bone structure of 40 species representative of the phylogenetic and ecology diversity of Carnivora. Remarkably, the results indicate that relative fill volume, relative structural complexity, elastic modulus, and relative maximum compressive strength of trabecular bone structure are not significantly related to phylogeny or ecology. The results reveal that morphological and mechanical performance attributes of trabecular bone structure are primarily influenced by body size, and that positive centroid size allometry and positive body mass allometry are present for structural complexity. The lack of feeding ecological signal in dorso-ventral compressive loading of temporomandibular joint models indicates that carnivoran temporomandibular joint trabecular structures may not undergo significant differential remodeling as an evolutionary response to different mechanically demanding feeding tasks.
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Affiliation(s)
- M. Aleksander Wysocki
- Graduate Program in Computational Cell Biology, Anatomy, and Pathology, Department of Pathology and Anatomical Sciences, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York, United States of America
- * E-mail:
| | - Z. Jack Tseng
- Graduate Program in Computational Cell Biology, Anatomy, and Pathology, Department of Pathology and Anatomical Sciences, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York, United States of America
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