1
|
On the Eating Habits of Sloths: Finite Element Analysis and Niche Specialization. J MAMM EVOL 2022. [DOI: 10.1007/s10914-022-09618-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
2
|
Wang B, Zelditch M, Badgley C. Geometric morphometrics of mandibles for dietary differentiation of Bovidae (Mammalia: Artiodactyla). Curr Zool 2022; 68:237-249. [PMID: 35592346 PMCID: PMC9113326 DOI: 10.1093/cz/zoab036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 04/27/2021] [Indexed: 11/13/2022] Open
Abstract
The mammalian family Bovidae has been widely studied in ecomorphological research, with important applications to paleoecological and paleohabitat reconstructions. Most studies of bovid craniomandibular features in relation to diet have used linear measurements. In this study, we conduct landmark-based geometric-morphometric analyses to evaluate whether different dietary groups can be distinguished by mandibular morphology. Our analysis includes data for 100 species of extant bovids, covering all bovid tribes and 2 dietary classifications. For the first classification with 3 feeding categories, we found that browsers (including frugivores), mixed feeders, and grazers are moderately well separated using mandibular shape. A finer dietary classification (frugivore, browser, browser-grazer intermediate, generalist, variable grazer, and obligate grazer) proved to be more useful for differentiating dietary extremes (frugivores and obligate grazers) but performed equally or less well for other groups. Notably, frugivorous bovids, which belong in tribe Cephalophini, have a distinct mandibular shape that is readily distinguished from all other dietary groups, yielding a 100% correct classification rate from jackknife cross-validation. The main differences in mandibular shape found among dietary groups are related to the functional needs of species during forage prehension and mastication. Compared with browsers, both frugivores and grazers have mandibles that are adapted for higher biomechanical demand of chewing. Additionally, frugivore mandibles are adapted for selective cropping. Our results call for more work on the feeding ecology and functional morphology of frugivores and offer an approach for reconstructing the diet of extinct bovids.
Collapse
Affiliation(s)
- Bian Wang
- Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI, 48109-1005, USA.,Museum of Paleontology, University of Michigan, Ann Arbor, MI, 48109-1085, USA
| | - Miriam Zelditch
- Museum of Paleontology, University of Michigan, Ann Arbor, MI, 48109-1085, USA
| | - Catherine Badgley
- Museum of Paleontology, University of Michigan, Ann Arbor, MI, 48109-1085, USA.,Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, 48109-1085, USA
| |
Collapse
|
3
|
Chatterji RM, Hipsley CA, Sherratt E, Hutchinson MN, Jones MEH. Ontogenetic allometry underlies trophic diversity in sea turtles (Chelonioidea). Evol Ecol 2022. [DOI: 10.1007/s10682-022-10162-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
AbstractDespite only comprising seven species, extant sea turtles (Cheloniidae and Dermochelyidae) display great ecological diversity, with most species inhabiting a unique dietary niche as adults. This adult diversity is remarkable given that all species share the same dietary niche as juveniles. These ontogenetic shifts in diet, as well as a dramatic increase in body size, make sea turtles an excellent group to examine how morphological diversity arises by allometric processes and life habit specialisation. Using three-dimensional geometric morphometrics, we characterise ontogenetic allometry in the skulls of all seven species and evaluate variation in the context of phylogenetic history and diet. Among the sample, the olive ridley (Lepidochelys olivacea) has a seemingly average sea turtle skull shape and generalised diet, whereas the green (Chelonia mydas) and hawksbill (Eretmochelys imbricata) show different extremes of snout shape associated with their modes of food gathering (grazing vs. grasping, respectively). Our ontogenetic findings corroborate previous suggestions that the skull of the leatherback (Dermochelys coriacea) is paedomorphic, having similar skull proportions to hatchlings of other sea turtle species and retaining a hatchling-like diet of relatively soft bodied organisms. The flatback sea turtle (Natator depressus) shows a similar but less extreme pattern. By contrast, the loggerhead sea turtle (Caretta caretta) shows a peramorphic signal associated with increased jaw muscle volumes that allow predation on hard shelled prey. The Kemp’s ridley (Lepidochelys kempii) has a peramorphic skull shape compared to its sister species the olive ridley, and a diet that includes harder prey items such as crabs. We suggest that diet may be a significant factor in driving skull shape differences among species. Although the small number of species limits statistical power, differences among skull shape, size, and diet are consistent with the hypothesis that shifts in allometric trajectory facilitated diversification in skull shape as observed in an increasing number of vertebrate groups.
Collapse
|
4
|
A new ankylosaurid from the Upper Cretaceous Nemegt Formation of Mongolia and implications for paleoecology of armoured dinosaurs. Sci Rep 2021; 11:22928. [PMID: 34824329 PMCID: PMC8616956 DOI: 10.1038/s41598-021-02273-4] [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: 07/08/2021] [Accepted: 11/11/2021] [Indexed: 11/08/2022] Open
Abstract
A new ankylosaurid dinosaur, Tarchia tumanovae sp. nov., has been recovered from the Upper Cretaceous Nemegt Formation of Mongolia. It includes a well-preserved skull, dorsal, sacral, caudal vertebrae, sixteen dorsal ribs, ilia, a partial ischium, free osteoderms, and a tail club. The squamosal horns of T. tumanovae are divided into two layers, the external dermal layer and the underlying squamosal horn proper. The irregular ventral margin of the base of the upper dermal layer may represent a resorption surface, suggesting that the squamosal horns of some ankylosaurids underwent extreme ontogenetic remodeling. Localized pathologies on the dorsosacral ribs and the tail provide evidence of agonistic behaviour. The tail club knob asymmetry of T. tumanovae resulted from restricted bone growth due to tail club strikes. Furthermore, T. tumanovae had an anteriorly protruded shovel-shaped beak, which is a morphological character of selective feeders. Ankylosaurid diets shifted from low-level bulk feeding to selective feeding during the Baruungoyot and the Nemegt "age" (middle Campanian-lower Maastrichtian). This ankylosaurid niche shifting might have been a response to habitat change and competition with other bulk-feeding herbivores.
Collapse
|
5
|
Böhmer C, Böhmer E. Skull Shape Diversity in Pet Rabbits and the Applicability of Anatomical Reference Lines for Objective Interpretation of Dental Disease. Vet Sci 2020; 7:vetsci7040182. [PMID: 33233758 PMCID: PMC7711434 DOI: 10.3390/vetsci7040182] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 11/15/2020] [Accepted: 11/18/2020] [Indexed: 11/16/2022] Open
Abstract
Acquired dental problems are among the most frequently encountered diseases in pet rabbits. However, early symptoms are often overlooked because the affected animals first appear completely asymptomatic. Alterations from anatomical reference lines according to Böhmer and Crossley applied to standard skull X-ray images, have been shown to be indicative of tooth health problems in pet rabbits. Despite its proven usefulness, there are exceptions in which the anatomical reference lines appear not to be suitable for application. We addressed this issue by quantifying the cranial morphology of a large data set of pet rabbit patients (N = 80). The results of the morphometric analyses revealed considerable diversity in skull shape among the typical pet rabbits, but variance in only a few parameters influences the applicability of the anatomical reference lines. The most substantial parameter is the palatal angle. Specimens in which the anatomical reference lines could not be applied, have a rather large angle between the skull base and the palatal bone. We recommend to measure the palatal angle before applying the anatomical reference lines for objective interpretation of dental disease. Pet rabbits with a palatal angle larger than 18.8° are not strictly suitable for the successful application of the anatomical reference lines.
Collapse
Affiliation(s)
- Christine Böhmer
- UMR 7179 CNRS/MNHN, Département Adaptations du Vivant, Muséum National D’Histoire Naturelle, CP 55, 57 rue Cuvier, 75005 Paris, France
- Correspondence:
| | - Estella Böhmer
- Chirurgische und Gynäkologische Kleintierklinik, Tierärztliche Fakultät, Ludwig-Maximilians-Universität München, Veterinärstr 13, 80539 München, Germany;
| |
Collapse
|
6
|
Tracing the Paleobiology of Paedotherium and Tremacyllus (Pachyrukhinae, Notoungulata), the Latest Sciuromorph South American Native Ungulates – Part I: Snout and Masticatory Apparatus. J MAMM EVOL 2020. [DOI: 10.1007/s10914-020-09516-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
7
|
Xafis A, Mayda S, Alçiçek MC, Kaya T, Halaçlar K, Grímsson F, Nagel D. Large giraffids (Mammalia, Ruminantia) from the new late Miocene fossiliferous locality of Kemiklitepe-E (Western Anatolia, Turkey). PALAEOBIODIVERSITY AND PALAEOENVIRONMENTS 2020; 101:853-867. [PMID: 34721707 PMCID: PMC8550776 DOI: 10.1007/s12549-020-00433-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 02/14/2020] [Accepted: 04/29/2020] [Indexed: 06/13/2023]
Abstract
Kemiklitepe is a well-known locality with four recognised fossiliferous horizons, KTA to KTD, which have yielded a plethora of mammalian remains. Previous taxonomic studies indicate the presence of three giraffid taxa: Samotherium major and Palaeotragus rouenii from the uppermost three horizons, KTA, KTB and KTC, as well as Palaeotragus rouenii and Samotherium? sp. from the lowermost KTD horizon. In this study a new locality, Kemiklitepe-E, is presented for the first time. Kemiklitepe-E is located approximately 350 m NW of the classic Kemiklitepe locality. The fossiliferous sedimentary rocks at Kemiklitepe-E occur at the same stratigraphic level as localities KTA, KTB and KTC. The preliminary faunal list includes representatives of Proboscidea, Chalicotheriidae, Equidae, Bovidae and Giraffidae. Comprehensive descriptions and comparisons of the Kemiklitepe-E Giraffidae specimens suggest the co-occurrence of two large giraffids: Samotherium major and Helladotherium duvernoyi. Samotherium major, previously documented from this region, is the most common taxon at Kemiklitepe. Helladotherium duvernoyi is rare at Kemiklitepe and here reported for the first time. The two taxa coexisted during the middle Turolian in Greece and Western Anatolia. In addition, it is suggested that specimens of Samotherium? sp described from KTD possibly belong to Samotherium neumayri. Based on the stratigraphic position of fossiliferous rocks, as well as the faunal data presented herein, the newly discovered locality is considered to be of middle Turolian (MN12) age.
Collapse
Affiliation(s)
- Alexandros Xafis
- Department of Palaeontology, Faculty of Earth Sciences, University of Vienna, 1090 Vienna, Austria
| | - Serdar Mayda
- Department of Biology, Faculty of Science, Ege University, 35100 Izmir, Turkey
| | | | - Tanju Kaya
- Natural History Museum, Ege University, 35100 Izmir, Turkey
| | - Kazım Halaçlar
- Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, 100044 China
| | - Friðgeir Grímsson
- Department of Botany and Biodiversity Research, University of Vienna, 1030 Vienna, Austria
| | - Doris Nagel
- Department of Palaeontology, Faculty of Earth Sciences, University of Vienna, 1090 Vienna, Austria
| |
Collapse
|
8
|
Xafis A, Saarinen J, Bastl K, Nagel D, Grímsson F. Palaeodietary traits of large mammals from the middle Miocene of Gračanica (Bugojno Basin, Bosnia-Herzegovina). PALAEOBIODIVERSITY AND PALAEOENVIRONMENTS 2020; 100:457-477. [PMID: 32647552 PMCID: PMC7320953 DOI: 10.1007/s12549-020-00435-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 05/04/2020] [Accepted: 05/09/2020] [Indexed: 06/11/2023]
Abstract
Recent excavations at the Gračanica coal mine (Bugojno Basin, Bosnia-Herzegovina) have unearthed numerous skeletal parts of fossil vertebrates, including a noteworthy collection of mammalian remains. Previous palaeoecological investigations of the Dinarides Lake System were established using stratigraphical, palaeofloral, and malacological data. However, large mammal remains have so far not been used to reconstruct the terrestrial palaeoenvironment of this important fossil ecosystem. Here, the palaeodietary preferences of large mammals were investigated, using a multiproxy approach by employing dental microwear and dental mesowear analysis, in order to provide new perspectives on the terrestrial palaeoecology of the Dinarides Lake System. The dental microwear of all available adult mammalian teeth was analysed. Dental mesowear analysis was employed for ungulate and proboscidean taxa, using mesowear scores and mesowear angles, respectively. The analysis reveals the presence of browsing, "dirty browsing", and mixed-feeding herbivorous taxa, with seasonal fruit, or even grass intake. Additionally, the analysis of the carnivores suggests the presence of hyaena- and cheetah-like hypercarnivores, as well as generalists. The palaeodietary traits of the fossil mammals suggest a closed canopy-like environment, which is supported by the fossil plant assemblage. Palaeopalynological data confirm the omnipresence of fleshy fruit-bearing plants, herbaceous taxa, as well as grasses, which justifies the seasonal fruit browsing, the common "dirty browsing", and the occasional grazing behaviour visualized for some of the fossil mammals from Gračanica.
Collapse
Affiliation(s)
- Alexandros Xafis
- Department of Palaeontology, Faculty of Earth Sciences, University of Vienna, 1090 Vienna, Austria
| | - Juha Saarinen
- Department of Geosciences and Geography, University of Helsinki, Helsinki, Finland
| | - Katharina Bastl
- Department of Palaeontology, Faculty of Earth Sciences, University of Vienna, 1090 Vienna, Austria
- Department of Oto-Rhino-Laryngology, Research Group Aerobiology and Pollen Information, Medical University of Vienna, Vienna, Austria
| | - Doris Nagel
- Department of Palaeontology, Faculty of Earth Sciences, University of Vienna, 1090 Vienna, Austria
| | - Friðgeir Grímsson
- Department of Botany and Biodiversity Research, University of Vienna, 1030 Vienna, Austria
| |
Collapse
|
9
|
Boscaini A, Gaudin TJ, Toledo N, Quispe BM, Antoine PO, Pujos F. The earliest well-documented occurrence of sexual dimorphism in extinct sloths: evolutionary and palaeoecological insights. Zool J Linn Soc 2019. [DOI: 10.1093/zoolinnean/zlz011] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
Sexual dimorphism (SD) is extremely common in species that have reproductive roles segregated into separate sexes, and it has been recognized in several mammalian lineages, both extant and extinct. Sexual dimorphism is low to moderate in living sloths, but it had a more important role for extinct sloth taxa. The presence of SD in extinct sloths was first suggested at the end of the 19th century and it is now commonly advocated as a possible explanation of high intraspecific variation in many extinct sloth species. In this paper, we report the presence of SD in Simomylodon uccasamamensis, a Late Miocene to Late Pliocene sloth from the Bolivian Altiplano. We present evidence of SD in the morphology of cranial and postcranial remains, representing the earliest unequivocal occurrence of size-based SD in an extinct sloth species. Differences between sexes are mainly observed in the morphology of the feeding apparatus and general body size. Comparisons with extant large mammals allow us to hypothesize different food selection between the two sexes, with probable divergent habitat use and concomitant niche separation. This, in turn, could have represented an important selective factor for adaptation to environmental changes experienced by the Bolivian Altiplano in Late Neogene times.
Collapse
Affiliation(s)
- Alberto Boscaini
- Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales (IANIGLA), CCT-CONICET-Mendoza, Parque Gral. San Martín, Mendoza, Argentina
| | - Timothy J Gaudin
- Department of Biology, Geology, and Environmental Science, University of Tennessee at Chattanooga, Chattanooga TN, USA
| | - Néstor Toledo
- División Paleontología Vertebrados, Museo de La Plata, Unidades de Investigación Anexo Museo, La Plata, Argentina
| | - Bernardino Mamani Quispe
- Departamento de Paleontología, Museo Nacional de Historia Natural de Bolivia, Cota Cota, La Paz, Bolivia
| | - Pierre-Olivier Antoine
- Institut des Sciences de l’Évolution de Montpellier, cc64, CNRS, Univ. Montpellier, IRD, EPHE, Montpellier, France
| | - François Pujos
- Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales (IANIGLA), CCT-CONICET-Mendoza, Parque Gral. San Martín, Mendoza, Argentina
| |
Collapse
|
10
|
Hou S, Cydylo M, Danowitz M, Solounias N. Comparisons of Schansitherium tafeli with Samotherium boissieri (Giraffidae, Mammalia) from the Late Miocene of Gansu Province, China. PLoS One 2019; 14:e0211797. [PMID: 30753231 PMCID: PMC6376930 DOI: 10.1371/journal.pone.0211797] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 01/21/2019] [Indexed: 12/02/2022] Open
Abstract
We are describing and figuring for the first time skulls of
Schansitherium tafeli, which are abundant in the Gansu area
of China from the Late Miocene. They were animals about the size of
Samotherium with shorter necks that had two pairs of
ossicones that merge at the base, which is unlike Samotherium.
The anterior ossicones consist of anterior lineations, which may represent
growth lines. They were likely mixed feeders similar to
Samotherium. Schansitherium is tentatively
placed in a very close position to Samotherium.
Samotherium and Schansitherium represent a
pair of morphologically very similar species that likely coexisted similarly to
pairs of modern species, where the main difference is in the ossicones. Pairs of
ruminants in Africa, for example, exist today that differ mostly in their horn
shape but otherwise are similar in size, shape, and diet. The absence of
Schansitherium from Europe is interesting, however, as
Samotherium is found in both locations. While is it
challenging to interpret neck length and ossicone shape in terms of function in
combat, we offer our hypothesis as to how the two species differed in their
fighting techniques.
Collapse
Affiliation(s)
- Sukuan Hou
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese
Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology,
Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Life and Paleoenvironment, Beijing,
China
- College of Earth and Planetary Sciences, University of Chinese Academy of
Sciences, Beijing, China
- * E-mail:
| | - Michael Cydylo
- Department of Anatomy, New York Institute of Technology College of
Osteopathic Medicine, Old Westbury, NY, United States of
America
| | - Melinda Danowitz
- Department of Pediatrics, Alfred I. duPont Hospital for Children,
Wilmington, DE, United States of America
| | - Nikos Solounias
- Department of Anatomy, New York Institute of Technology College of
Osteopathic Medicine, Old Westbury, NY, United States of
America
- Department of Paleontology, American Museum of Natural History, New York,
NY, United States of America
| |
Collapse
|
11
|
Forrest FL, Plummer TW, Raaum RL. Ecomorphological analysis of bovid mandibles from Laetoli Tanzania using 3D geometric morphometrics: Implications for hominin paleoenvironmental reconstruction. J Hum Evol 2018; 114:20-34. [DOI: 10.1016/j.jhevol.2017.09.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2014] [Revised: 09/16/2017] [Accepted: 09/23/2017] [Indexed: 11/16/2022]
|
12
|
Ríos M, Sánchez IM, Morales J. A new giraffid (Mammalia, Ruminantia, Pecora) from the late Miocene of Spain, and the evolution of the sivathere-samothere lineage. PLoS One 2017; 12:e0185378. [PMID: 29091914 PMCID: PMC5665556 DOI: 10.1371/journal.pone.0185378] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 08/31/2017] [Indexed: 11/19/2022] Open
Abstract
Giraffids include the only living giraffomorph ruminants and are diagnosed by the presence of bi-lobed canines and a special type of epiphyseal cranial appendages called ossicones. The family Giraffidae ranges from the latest early Miocene until today. However they are currently extant relics with only two living representatives, the African genera Okapia and Giraffa. Giraffids were much more diverse and widespread in the past, with more than 30 fossil species described. For the past decades a number of studies intended to resolve the phylogenetic relationships of the family, but due to the lack of really good cranial material no clear consensus was reached regarding the phylogenetic relationships amongst the different members of the group. The exceptionally complete remains of a new large giraffid from the late Miocene of Spain, Decennatherium rex sp. nov., allows us to improve and reassess giraffid systematics, offering a lot of new data, both anatomic and phylogenetic, on the large late Miocene giraffids of Eurasia. The results of our cladistic analysis show Decennatherium as a basal offshoot of a clade containing the gigantic samotheres and sivatheres, characterized by the presence of a Sivatherium-like ossicone-plan among other features. Decennatherium thus offers the most ancient evidence of this Sivatherium-plan and firmly establishes the early morphological patterns of evolution of a sivathere / samothere-clade that is defined as the less inclusive clade that contains Decennatherium and Sivatherium. Finally, this large group of four-ossiconed giraffids evolutionarily links Miocene Europe and Africa indicating vicariance / migration processes among the giraffid genetic pools separated by the Mediterranean Sea.
Collapse
Affiliation(s)
- María Ríos
- Departamento de Paleobiología, Museo Nacional de Ciencias Naturales-CSIC, Madrid, Spain
- * E-mail:
| | - Israel M. Sánchez
- Departmento de Faunas del Neógeno y Cuaternario, Institut Català de Paleontologia- Miquel Crusafont, Barcelona, Spain
| | - Jorge Morales
- Departamento de Paleobiología, Museo Nacional de Ciencias Naturales-CSIC, Madrid, Spain
| |
Collapse
|
13
|
Meier AR, Schmuck U, Meloro C, Clauss M, Hofmann RR. Convergence of macroscopic tongue anatomy in ruminants and scaling relationships with body mass or tongue length. J Morphol 2016; 277:351-62. [DOI: 10.1002/jmor.20501] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Revised: 11/12/2015] [Accepted: 11/14/2015] [Indexed: 11/05/2022]
Affiliation(s)
- Andrea R. Meier
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty; University of Zurich; Winterthurerstrasse 260 Zurich 8057 Switzerland
| | - Ute Schmuck
- Tierärztliche Praxis Für Kleintiere; Soestenstrasse 26 Cloppenburg 49661 Germany
| | - Carlo Meloro
- Research Centre in Evolutionary Anthropology and Palaeoecology, School of Natural Sciences and Psychology; Liverpool John Moores University; James Parsons Building Byrom Street Liverpool L3 3AF UK
| | - Marcus Clauss
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty; University of Zurich; Winterthurerstrasse 260 Zurich 8057 Switzerland
| | | |
Collapse
|
14
|
Mitchell G, Roberts D, van Sittert S. The digestive morphophysiology of wild, free-living, giraffes. Comp Biochem Physiol A Mol Integr Physiol 2015; 187:119-29. [DOI: 10.1016/j.cbpa.2015.05.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2015] [Revised: 05/19/2015] [Accepted: 05/19/2015] [Indexed: 11/25/2022]
|
15
|
Pavez-Fox MA, Pino M, Corti P. Muzzle morphology and food consumption by pudu (Pudu pudaMolina 1782) in south-central Chile. STUDIES ON NEOTROPICAL FAUNA AND ENVIRONMENT 2015. [DOI: 10.1080/01650521.2015.1050920] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
16
|
Varela L, Fariña RA. Masseter moment arm as a dietary proxy in herbivorous ungulates. J Zool (1987) 2015. [DOI: 10.1111/jzo.12246] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- L. Varela
- Sección Paleontología; Facultad de Ciencias; Universidad de la República; Montevideo Uruguay
| | - R. A. Fariña
- Sección Paleontología; Facultad de Ciencias; Universidad de la República; Montevideo Uruguay
| |
Collapse
|
17
|
Abstract
Snout shape is a prominent aspect of herbivore feeding ecology, interacting with both forage selectivity and intake rate. Previous investigations have suggested ruminant feeding styles can be discriminated via snout shape, with grazing and browsing species characterised by ‘blunt’ and ‘pointed’ snouts respectively, often with specification of an ‘intermediate’ sub-grouping to represent ambiguous feeding styles and/or morphologies. Snout shape morphology is analysed here using a geometric morphometric approach to compare the two-dimensional profiles of the premaxilla in ventral aspect for a large sample of modern ruminant species, for which feeding modes are known from secondary criteria. Results suggest that, when browsing and grazing ruminants are classified ecologically based on a range of feeding style indicators, they cannot be discriminated unambiguously on the basis of snout profile shape alone. Profile shapes in our sample form a continuum with substantial overlap between groupings and a diverse range of morphologies. Nevertheless, we obtained an 83.8 percent ratio of correct post hoc feeding style categorisations based on the proximity of projected profile shapes to group centroids in the discriminant space. Accordingly, this procedure for identifying species whose feeding strategy is ‘unknown’ can be used with a reasonable degree of confidence, especially if backed-up by additional information. Based on these results we also refine the definitions of snout shape varieties, taking advantage of the descriptive power that geometric morphometrics offers to characterize the morphological disparities observed. The shape variance exhibited by both browsing and grazing ruminants corresponds strongly to body mass, providing further evidence for an interaction between snout shape, feeding style, and body size evolution. Finally, by exploring the role of phylogenetic similarity in snout shape, we find a slight increase in successful categorisation when repeating the analysis with phylogenetic control on the geometric profiles.
Collapse
Affiliation(s)
- Jonathan P. Tennant
- Department of Earth Science and Engineering, Imperial College London, London, United Kingdom
- * E-mail:
| | - Norman MacLeod
- Earth Science Department, The Natural History Museum, London, United Kingdom
| |
Collapse
|
18
|
Louys J, Faith JT. Phylogenetic topology mapped onto dietary ecospace reveals multiple pathways in the evolution of the herbivorous niche in African Bovidae. J ZOOL SYST EVOL RES 2014. [DOI: 10.1111/jzs.12080] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Julien Louys
- School of Culture, History and Languages; Australian National University; Canberra ACT Australia
| | - J. Tyler Faith
- School of Social Science; The University of Queensland; Brisbane Qld Australia
| |
Collapse
|
19
|
Solounias N, Tariq M, Hou S, Danowitz M, Harrison M. A New Method of Tooth Mesowear and a Test of it on Domestic Goats. ANN ZOOL FENN 2014. [DOI: 10.5735/086.051.0212] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
20
|
Cantalapiedra JL, Fitzjohn RG, Kuhn TS, Fernández MH, DeMiguel D, Azanza B, Morales J, Mooers AØ. Dietary innovations spurred the diversification of ruminants during the Caenozoic. Proc Biol Sci 2013; 281:20132746. [PMID: 24352949 DOI: 10.1098/rspb.2013.2746] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Global climate shifts and ecological flexibility are two major factors that may affect rates of speciation and extinction across clades. Here, we connect past climate to changes in diet and diversification dynamics of ruminant mammals. Using novel versions of Multi-State Speciation and Extinction models, we explore the most likely scenarios for evolutionary transitions among diets in this clade and ask whether ruminant lineages with different feeding styles (browsing, grazing and mixed feeding) underwent differential rates of diversification concomitant with global temperature change. The best model of trait change had transitions from browsers to grazers via mixed feeding, with appreciable rates of transition to and from grazing and mixed feeding. Diversification rates in mixed-feeder and grazer lineages tracked the palaeotemperature curve, exhibiting higher rates during the Miocene thermal maxima. The origination of facultative mixed diet and grazing states may have triggered two adaptive radiations--one during the Oligocene-Miocene transition and the other during Middle-to-Late Miocene. Our estimate of mixed diets for basal lineages of both bovids and cervids is congruent with fossil evidence, while the reconstruction of browser ancestors for some impoverished clades--Giraffidae and Tragulidae--is not. Our results offer model-based neontological support to previous palaeontological findings and fossil-based hypothesis highlighting the importance of dietary innovations--especially mixed feeding--in the success of ruminants during the Neogene.
Collapse
Affiliation(s)
- Juan L Cantalapiedra
- Departmento de Paleobiología, Museo Nacional de Ciencias Naturales, Consejo Superior de Investigaciones Científicas, , Pinar 25, 28006 Madrid, Spain, Department of Biological Sciences, Simon Fraser University, , 8888 University Drive, Burnaby, British Columbia V5A 1S6, Canada, IRMACS, Simon Fraser University, , 8888 University Drive, Burnaby, British Columbia V5A 1S6, Canada, Departamento de Paleontología, Facultad de Ciencias Geológicas, Universidad Complutense de Madrid, , José Antonio Novais 2, Madrid 28040, Spain, Department of Zoology, University of British Columbia, , Vancouver, British Columbia V6T 1Z4, Canada, Department of Biological Sciences, Macquarie University, , Sydney, New South Wales 2109, Australia, Departamento de Cambio Medioambiental, Instituto de Geociencias (UCM, CSIC), , José Antonio Novais 2, Madrid 28040, Spain, Departament de Faunes del Neogen i Quaternari, Institut Català de Paleontologia Miquel Crusafont, Edifici ICP, Universitat Autònoma de Barcelona, , Cerdanyola del Vallès 08193, Spain, Departamento de Ciencias de la Tierra, Facultad de Ciencias, Universidad de Zaragoza, , Pedro Cerbuna 12, Zaragoza 50009, Spain
| | | | | | | | | | | | | | | |
Collapse
|
21
|
Giannini NP, García-López DA. Ecomorphology of Mammalian Fossil Lineages: Identifying Morphotypes in a Case Study of Endemic South American Ungulates. J MAMM EVOL 2013. [DOI: 10.1007/s10914-013-9233-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
22
|
Skull ecomorphology of megaherbivorous dinosaurs from the dinosaur park formation (upper campanian) of Alberta, Canada. PLoS One 2013; 8:e67182. [PMID: 23874409 PMCID: PMC3707905 DOI: 10.1371/journal.pone.0067182] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Accepted: 05/15/2013] [Indexed: 11/19/2022] Open
Abstract
Megaherbivorous dinosaur coexistence on the Late Cretaceous island continent of Laramidia has long puzzled researchers, owing to the mystery of how so many large herbivores (6–8 sympatric species, in many instances) could coexist on such a small (4–7 million km2) landmass. Various explanations have been put forth, one of which–dietary niche partitioning–forms the focus of this study. Here, we apply traditional morphometric methods to the skulls of megaherbivorous dinosaurs from the Dinosaur Park Formation (upper Campanian) of Alberta to infer the ecomorphology of these animals and to test the niche partitioning hypothesis. We find evidence for niche partitioning not only among contemporaneous ankylosaurs, ceratopsids, and hadrosaurids, but also within these clades at the family and subfamily levels. Consubfamilial ceratopsids and hadrosaurids differ insignificantly in their inferred ecomorphologies, which may explain why they rarely overlap stratigraphically: interspecific competition prevented their coexistence.
Collapse
|
23
|
Mallon JC, Evans DC, Ryan MJ, Anderson JS. Feeding height stratification among the herbivorous dinosaurs from the Dinosaur Park Formation (upper Campanian) of Alberta, Canada. BMC Ecol 2013; 13:14. [PMID: 23557203 PMCID: PMC3637170 DOI: 10.1186/1472-6785-13-14] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Accepted: 03/01/2013] [Indexed: 11/10/2022] Open
Abstract
Background Herbivore coexistence on the Late Cretaceous island continent of Laramidia has been a topic of great interest, stemming from the paradoxically high diversity and biomass of these animals in relation to the relatively small landmass available to them. Various hypotheses have been advanced to account for these facts, of which niche partitioning is among the most frequently invoked. However, despite its wide acceptance, this hypothesis has not been rigorously tested. This study uses the fossil assemblage from the Dinosaur Park Formation of Alberta as a model to investigate whether niche partitioning facilitated herbivorous dinosaur coexistence on Laramidia. Specifically, the question of feeding height stratification is examined in light of the role it plays in facilitating modern ungulate coexistence. Results Most herbivorous dinosaur species from the Dinosaur Park Formation were restricted to feeding no higher than approximately 1 m above the ground. There is minimal evidence for feeding height partitioning at this level, with ceratopsids capable of feeding slightly higher than ankylosaurs, but the ecological significance of this is ambiguous. Hadrosaurids were uniquely capable of feeding up to 2 m quadrupedally, or up to 5 m bipedally. There is no evidence for either feeding height stratification within any of these clades, or for change in these ecological relationships through the approximately 1.5 Ma record of the Dinosaur Park Formation. Conclusions Although we cannot reject the possibility, we find no good evidence that feeding height stratification, as revealed by reconstructed maximum feeding heights, played an important role in facilitating niche partitioning among the herbivorous dinosaurs of Laramidia. Most browsing pressure was concentrated in the herb layer, although hadrosaurids were capable of reaching shrubs and low-growing trees that were out of reach from ceratopsids, ankylosaurs, and other small herbivores, effectively dividing the herbivores in terms of relative abundance. Sympatric hadrosaurids may have avoided competing with one another by feeding differentially using bipedal and quadrupedal postures. These ecological relationships evidently proved to be evolutionarily stable because they characterize the herbivore assemblage of the Dinosaur Park Formation through time. If niche partitioning served to facilitate the rich diversity of these animals, it may have been achieved by other means in addition to feeding height stratification. Consideration of other feeding height proxies, including dental microwear and skull morphology, may help to alleviate problems of underdetermination identified here.
Collapse
Affiliation(s)
- Jordan C Mallon
- Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada.
| | | | | | | |
Collapse
|
24
|
|
25
|
Fraser D, Theodor JM. Comparing ungulate dietary proxies using discriminant function analysis. J Morphol 2011; 272:1513-26. [DOI: 10.1002/jmor.11001] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Revised: 04/11/2011] [Accepted: 05/29/2011] [Indexed: 11/11/2022]
|
26
|
Diet of Mongolian gazelles and Tibetan antelopes from steppe habitats using premaxillary shape, tooth mesowear and microwear analyses. Mamm Biol 2011. [DOI: 10.1016/j.mambio.2011.01.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
27
|
Whitlock JA. Inferences of diplodocoid (Sauropoda: Dinosauria) feeding behavior from snout shape and microwear analyses. PLoS One 2011; 6:e18304. [PMID: 21494685 PMCID: PMC3071828 DOI: 10.1371/journal.pone.0018304] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Accepted: 02/24/2011] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND As gigantic herbivores, sauropod dinosaurs were among the most important members of Mesozoic communities. Understanding their ecology is fundamental to developing a complete picture of Jurassic and Cretaceous food webs. One group of sauropods in particular, Diplodocoidea, has long been a source of debate with regard to what and how they ate. Because of their long lineage duration (Late Jurassic-Late Cretaceous) and cosmopolitan distribution, diplodocoids formed important parts of multiple ecosystems. Additionally, fortuitous preservation of a large proportion of cranial elements makes them an ideal clade in which to examine feeding behavior. METHODOLOGY/PRINCIPAL FINDINGS Hypotheses of various browsing behaviors (selective and nonselective browsing at ground-height, mid-height, or in the upper canopy) were examined using snout shape (square vs. round) and dental microwear. The square snouts, large proportion of pits, and fine subparallel scratches in Apatosaurus, Diplodocus, Nigersaurus, and Rebbachisaurus suggest ground-height nonselective browsing; the narrow snouts of Dicraeosaurus, Suuwassea, and Tornieria and the coarse scratches and gouges on the teeth of Dicraeosaurus suggest mid-height selective browsing in those taxa. Comparison with outgroups (Camarasaurus and Brachiosaurus) reinforces the inferences of ground- and mid-height browsing and the existence of both non-selective and selective browsing behaviors in diplodocoids. CONCLUSIONS/SIGNIFICANCE These results reaffirm previous work suggesting the presence of diverse feeding strategies in sauropods and provide solid evidence for two different feeding behaviors in Diplodocoidea. These feeding behaviors can subsequently be tied to paleoecology, such that non-selective, ground-height behaviors are restricted to open, savanna-type environments. Selective browsing behaviors are known from multiple sauropod clades and were practiced in multiple environments.
Collapse
Affiliation(s)
- John A Whitlock
- Museum of Paleontology, University of Michigan, Ann Arbor, Michigan, United States of America.
| |
Collapse
|
28
|
Raia P, Carotenuto F, Meloro C, Piras P, Pushkina D. The shape of contention: adaptation, history, and contingency in ungulate mandibles. Evolution 2009; 64:1489-503. [PMID: 20015238 DOI: 10.1111/j.1558-5646.2009.00921.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Mandibles and teeth of ungulates have been extensively studied to discern the functional significance of their design. Grazing ungulates have deeper mandibles, longer coronoid processes, flatter incisor arcades, and more hypsodont molars in comparison to browsers. If the functional significance of both mandible and teeth shapes is well-established, it remains uncertain to what extent mandible shapes are really adapted to grazing, meaning that they evolved either to serve their current biological function or just as a structural requirement to accommodate higher crowned molars. Here, we address this question by studying the contribution of phylogeny, hypsodonty, and body size to mandibular shape variation. The mandible shape appeared to be significantly influenced by hypsodonty but not by body size. Interestingly, hypsodonty-related changes influenced the tooth row in artiodactyls and perissodactyls significantly but in the opposite directions, which is ultimately related to their different digestive strategies. Yet, we obtained a strong phylogenetic effect in perissodactyls, suggesting that their mandible shape should be strongly inherited. The strength of this effect was not significant within artiodactyls (where hypsodonty explained much more variance in mandible shape). Digestive strategy is deemed to interplay with hypsodonty to produce different paths of adaptation to particular diets in ungulates.
Collapse
Affiliation(s)
- Pasquale Raia
- Dipartimento di Scienze della Terra, Università degli Studi di Napoli Federico II, L.go San, Marcellino 10, 80138, Napoli, Italy.
| | | | | | | | | |
Collapse
|
29
|
|
30
|
Mendoza M, Palmqvist P. Hypsodonty in ungulates: an adaptation for grass consumption or for foraging in open habitat? J Zool (1987) 2008. [DOI: 10.1111/j.1469-7998.2007.00365.x] [Citation(s) in RCA: 143] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
31
|
Clauss M, Kaiser T, Hummel J. The Morphophysiological Adaptations of Browsing and Grazing Mammals. ECOLOGICAL STUDIES 2008. [DOI: 10.1007/978-3-540-72422-3_3] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
|
32
|
Sereno PC, Wilson JA, Witmer LM, Whitlock JA, Maga A, Ide O, Rowe TA. Structural extremes in a cretaceous dinosaur. PLoS One 2007; 2:e1230. [PMID: 18030355 PMCID: PMC2077925 DOI: 10.1371/journal.pone.0001230] [Citation(s) in RCA: 217] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2007] [Accepted: 11/07/2007] [Indexed: 11/25/2022] Open
Abstract
Fossils of the Early Cretaceous dinosaur, Nigersaurus taqueti, document for the first time the cranial anatomy of a rebbachisaurid sauropod. Its extreme adaptations for herbivory at ground-level challenge current hypotheses regarding feeding function and feeding strategy among diplodocoids, the larger clade of sauropods that includes Nigersaurus. We used high resolution computed tomography, stereolithography, and standard molding and casting techniques to reassemble the extremely fragile skull. Computed tomography also allowed us to render the first endocast for a sauropod preserving portions of the olfactory bulbs, cerebrum and inner ear, the latter permitting us to establish habitual head posture. To elucidate evidence of tooth wear and tooth replacement rate, we used photographic-casting techniques and crown thin sections, respectively. To reconstruct its 9-meter postcranial skeleton, we combined and size-adjusted multiple partial skeletons. Finally, we used maximum parsimony algorithms on character data to obtain the best estimate of phylogenetic relationships among diplodocoid sauropods. Nigersaurus taqueti shows extreme adaptations for a dinosaurian herbivore including a skull of extremely light construction, tooth batteries located at the distal end of the jaws, tooth replacement as fast as one per month, an expanded muzzle that faces directly toward the ground, and hollow presacral vertebral centra with more air sac space than bone by volume. A cranial endocast provides the first reasonably complete view of a sauropod brain including its small olfactory bulbs and cerebrum. Skeletal and dental evidence suggests that Nigersaurus was a ground-level herbivore that gathered and sliced relatively soft vegetation, the culmination of a low-browsing feeding strategy first established among diplodocoids during the Jurassic.
Collapse
Affiliation(s)
- Paul C Sereno
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois, United States of America.
| | | | | | | | | | | | | |
Collapse
|
33
|
Merceron G, Schulz E, Kordos L, Kaiser TM. Paleoenvironment of Dryopithecus brancoi at Rudabánya, Hungary: evidence from dental meso- and micro-wear analyses of large vegetarian mammals. J Hum Evol 2007; 53:331-49. [PMID: 17719619 DOI: 10.1016/j.jhevol.2007.04.008] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2006] [Revised: 03/17/2007] [Accepted: 04/07/2007] [Indexed: 12/01/2022]
Abstract
The environment of the hominoid Dryopithecus brancoi at Rudabánya (Late Miocene of Hungary) is reconstructed here using the dietary traits of fossil ruminants and equids. Two independent approaches, dental micro- and meso-wear analyses, are applied to a sample of 73 specimens representing three ruminants: Miotragocerus sp. (Bovidae), Lucentia aff. pierensis (Cervidae), Micromeryx flourensianus (Moschidae), and one equid, Hippotherium intrans (Equidae). The combination of meso- and micro-wear signatures provides both long- and short-term dietary signals, and through comparisons with extant species, the feeding styles of the fossil species are reconstructed. Both approaches categorize the cervid as an intermediate feeder engaged in both browsing and grazing. The bovid Miotragocerus sp. is depicted as a traditional browser. Although the dental meso-wear pattern of the moschid has affinities with intermediate feeders, its dental micro-wear pattern also indicates significant intake of fruits and seeds. Hippotherium intrans was not a grazer and its dental micro-wear pattern significantly differs from that of living browsers, which may suggest that the fossil equid was engaged both in grazing and browsing. However, the lack of extant equids which are pure browsers prevents any definitive judgment on the feeding habits of Hippotherium. Based on these dietary findings, the Rudabánya paleoenvironment is reconstructed as a dense forest. The presence of two intermediate feeders indicates some clearings within this forest; however the absence of grazers suggests that these clearings were most likely confined. To demonstrate the ecological diversity among the late Miocene hominoids in Europe, the diet and habitat of Dryopithecus brancoi and Ouranopithecus macedoniensis (Greece) are compared.
Collapse
Affiliation(s)
- Gildas Merceron
- Zoological Institute and Museum, University of Hamburg, Martin-Luther-King Platz 3, 20146 Hamburg, Germany.
| | | | | | | |
Collapse
|
34
|
Ozaki M, Suwa G, Kaji K, Ohba T, Hosoi E, Koizumi T, Takatsuki S. Correlations between feeding type and mandibular morphology in the sika deer. J Zool (1987) 2007. [DOI: 10.1111/j.1469-7998.2006.00264.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
35
|
Bovid postcranial ecomorphological survey of the Laetoli paleoenvironment. J Hum Evol 2007; 52:663-80. [PMID: 17353031 DOI: 10.1016/j.jhevol.2007.01.001] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2006] [Revised: 12/03/2006] [Accepted: 01/03/2007] [Indexed: 10/23/2022]
Abstract
Here we report on a bovid postcranial ecomorphological survey of the fossil assemblages from the Plio-Pleistocene site of Laetoli, Tanzania. A global sample of extant bovids (n=205), cervids (n=14), and tragulids (n=5) from seven known habitat types constitutes the comparative data set. All long bones, carpals, tarsals, and phalanges were measured. Discriminant function analyses (DFA) were conducted in order to evaluate the ability of each element to accurately predict habitat affiliation. The baseline of chance accuracy for DFAs (i.e., the percentage of correct predictions that can be expected when habitat assignments are randomized) served as the cut-off point between good and bad habitat predictors. A total of 22 elements yielded percentages of correct classification over the baseline of accuracy, and these were extended to the Laetoli fossil assemblages. Summaries of the number of specimens predicted to belong to each habitat type were used to reconstruct the paleoenvironment. The results indicate that, at the time of the deposition of the Laetolil Beds, the area had heavy woodland-bushland cover with some lighter tree and bush cover and grass available. These results lend strong support to recent suggestions that the area was on the more wooded end of the habitat spectrum, contra initial conclusions that it represented a mosaic of more open habitats. The results also indicate that, during the deposition of the Ndolanya Beds, the environment had become more open and the grassland component of the environment had increased significantly. Light woodland-bushland and an abundance of grass cover dominated the landscape, although tracts of land with denser vegetation likely existed. This conclusion agrees with earlier suggestions that the area was a semiarid bushland.
Collapse
|
36
|
Trophic ecology of two savanna grazers, blue wildebeest Connochaetes taurinus and black wildebeest Connochaetes gnou. EUR J WILDLIFE RES 2006. [DOI: 10.1007/s10344-006-0070-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
37
|
Bargo MS, Toledo N, Vizcaíno SF. Muzzle of South American Pleistocene ground sloths (Xenarthra, Tardigrada). J Morphol 2006; 267:248-63. [PMID: 16315216 DOI: 10.1002/jmor.10399] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Sloths are among the most characteristic elements of the Cainozoic of South America and are represented, during the Pleistocene, by approximately nine genera of gigantic ground sloths (Megatheriidae and Mylodontidae). A few contributions have described their masticatory apparatus, but almost no attention has been paid to the reconstruction of the muzzle, an important feature to consider in relation to food intake, and particularly relevant in sloths because of the edentulous nature of the muzzle and its varied morphology. The relationship between dietary habits and shape and width of the muzzle is well documented in living herbivores and has been considered an important feature for the inference of alimentary styles in fossils, providing an interesting methodological tool that deserves to be considered for xenarthrans. The goal of this study was to examine models of food intake by reconstructing the appearance and shape of the muzzle in five species of Pleistocene ground sloths (Megatherium americanum, Glossotherium robustum, Lestodon armatus, Mylodon darwini, and Scelidotherium leptocephalum) using reconstructions of the nasal cartilages and facial muscles involved in food intake. The preservation of the nasal septum, and the scars for muscular attachment in the rostral part of the skulls, allow making a conservative reconstruction of muzzle anatomy in fossil sloths. Wide-muzzled ground sloths (Glossotherium and Lestodon) had a square, nonprehensile upper lip and were mostly bulk-feeders. The lips, coupled with the tongue, were used to pull out grass and herbaceous plants. Narrow-muzzled sloths (Mylodon, Scelidotherium, and Megatherium) had a cone-shaped and prehensile lip and were mixed or selective feeders. The prehensile lip was used to select particular plants or plant parts.
Collapse
Affiliation(s)
- M Susana Bargo
- División Paleontología Vertebrados, Museo de La Plata, and CIC-CONICET La Plata, Argentina.
| | | | | |
Collapse
|
38
|
Eronen JT, Rook L. The Mio-Pliocene European primate fossil record: dynamics and habitat tracking. J Hum Evol 2004; 47:323-41. [PMID: 15530351 DOI: 10.1016/j.jhevol.2004.08.003] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2003] [Accepted: 08/13/2004] [Indexed: 11/21/2022]
Abstract
We present here a study of European Neogene primate occurrences in the context of changing humidity. We studied the differences of primate localities versus non-primate localities by using the mammal communities and the ecomorphological data of the taxa present in the communities. The distribution of primates is influenced by humidity changes during the whole Neogene, and the results suggest that the primates track the changes in humidity through time. The exception to this is the Superfamily Cercopithecoidea which shows a wider range of choices in habitats. All primate localities seem to differ from non-primate localities in that the mammal community structure is more closed habitat oriented, while in non-primate localities the community structure changes towards open-habitat oriented in the late Neogene. The differences in primate and non-primate localities are stronger during the times of deep environmental change, when primates are found in their preferred habitats and non-primate localities have faunas better able to adapt to changing conditions.
Collapse
Affiliation(s)
- Jussi T Eronen
- Department of Geology, University of Helsinki, P.O. Box 64, FIN-00014, Finland.
| | | |
Collapse
|
39
|
Wood B, Strait D. Patterns of resource use in early Homo and Paranthropus. J Hum Evol 2004; 46:119-62. [PMID: 14871560 DOI: 10.1016/j.jhevol.2003.11.004] [Citation(s) in RCA: 132] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2002] [Accepted: 11/04/2003] [Indexed: 11/21/2022]
Abstract
Conventional wisdom concerning the extinction of Paranthropus suggests that these species developed highly derived morphologies as a consequence of specializing on a diet consisting of hard and/or low-quality food items. It goes on to suggest that these species were so specialized or stenotopic that they were unable to adapt to changing environments in the period following 1.5 Ma. The same conventional wisdom proposes that early Homo species responded very differently to the same environmental challenges. Instead of narrowing their niche it was the dietary and behavioral flexibility (eurytopy) exhibited by early Homo that enabled that lineage to persist. We investigate whether evidence taken across eleven criteria supports a null hypothesis in which Paranthropus is more stenotopic than early Homo. In six instances (most categories of direct evidence of dietary breadth, species diversity, species duration, susceptibility to dispersal, dispersal direction, and non-dietary adaptations) the evidence is inconsistent with the hypothesis. Only one line of indirect evidence for dietary breadth-occlusal morphology-is unambiguously consistent with the null hypothesis that Paranthropus' ability to process tough, fibrous food items (e.g., leaves) was reduced relative to early Homo. Other criteria (habitat preference, population density, direct and indirect evidence of dietary breadth related to incisor use) are only consistent with the hypothesis under certain conditions. If those conditions are not met, then the evidence is either inconsistent with the hypothesis, or ambiguous. On balance, Paranthropus and early Homo were both likely to have been ecological generalists. These data are inconsistent with the conventional wisdom that stenotopy was a major contributing factor in the extinction of the Paranthropus clade. Researchers will need to explore other avenues of research in order to generate testable hypotheses about the demise of Paranthropus. Ecological models that may explain the evolution of eurytopy in early hominins are discussed.
Collapse
Affiliation(s)
- Bernard Wood
- CASHP and Department of Anthropology, The George Washington University, 2110 G St. NW, Washington, DC 20052, USA
| | | |
Collapse
|
40
|
Kaiser TM, Fortelius M. Differential mesowear in occluding upper and lower molars: opening mesowear analysis for lower molars and premolars in hypsodont horses. J Morphol 2003; 258:67-83. [PMID: 12905535 DOI: 10.1002/jmor.10125] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A new approach of reconstructing ungulate diet, the mesowear method, was recently introduced by Fortelius and Solounias ([2000] Am Mus Novitat 3301:1-36). Mesowear is based on facet development on the occlusal surfaces of the teeth. Restricting mesowear investigation to maxillary cheek teeth would allow mesowear investigation only in assemblages of large numbers of individuals and therefore would generally restrict this method to relatively few assemblages of recent and fossil ungulates. Most of the fossil, subfossil, and recent ungulate osteological assemblages that may be assigned to a single taxon have smaller numbers of individuals. This results in a demand to extend the mesowear method to further tooth positions in order to obtain stable dietary classifications of fossil taxa. The focus of this article is to test if a consistent mesowear classification is obtainable for mandibular as well as for maxillary teeth. For statistical testing, large assemblages of isolated cheek teeth of the Vallesian hipparionine horse Hippotherium primigenium and of the recent zebra Equus burchelli were employed as models. The upper tooth positions P4, M1, M2, and M3 as suggested by Kaiser and Solounias (2003) as the model for the "extended" mesowear method and the lower tooth positions P4-M3 were tested for their consistency in classification of the mesowear variables. We found a considerable shift of the mesowear signature towards the grazing edge of the mesowear continuum in lower cheek teeth. In order to adjust the signal of lower teeth to the signal of the upper teeth, a calibration factor was introduced which allowed incorporation of lower cheek teeth into the same model of mesowear investigation together with upper cheek teeth. We propose that this model is particularly suited for the reconstruction of paleodiets in hypsodont hipparionine and equine equids. We further investigated the functional relation between the mesowear profiles and the distribution of dental tissues along the course of the occlusal contact. We therefore correlated mesowear profiles with enamel distribution profiles and found the mesowear profile to be strongly controlled by the attritional environment encountered by a given apex area. The differential signal observed in cusp apex morphology between upper and lower cheek teeth was found to be more closely related to attrition by the antagonistic tooth than to the distribution of dental tissues in the tooth under consideration. The results suggest a general extension of the mesowear method of paleodiet reconstruction and a basic scenario for the evolution of anisodont dentitions.
Collapse
Affiliation(s)
- Thomas M Kaiser
- Zoological Institute and Museum, University Greifswald, D-17489 Greifswald, Germany.
| | | |
Collapse
|
41
|
MITCHELL G, Skinner JD. On the origin, evolution and phylogeny of giraffes Giraffa camelopardalis. ACTA ACUST UNITED AC 2003. [DOI: 10.1080/00359190309519935] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
42
|
Characterizing complex craniodental patterns related to feeding behaviour in ungulates: a multivariate approach. J Zool (1987) 2002. [DOI: 10.1017/s0952836902001346] [Citation(s) in RCA: 147] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
43
|
SOLOUNIAS NIKOS, SEMPREBON GINA. Advances in the Reconstruction of Ungulate Ecomorphology with Application to Early Fossil Equids. AMERICAN MUSEUM NOVITATES 2002. [DOI: 10.1206/0003-0082(2002)366<0001:aitrou>2.0.co;2] [Citation(s) in RCA: 314] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
44
|
MacFadden BJ. Cenozoic Mammalian Herbivores From the Americas: Reconstructing Ancient Diets and Terrestrial Communities. ACTA ACUST UNITED AC 2000. [DOI: 10.1146/annurev.ecolsys.31.1.33] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Bruce J. MacFadden
- Florida Museum of Natural History, University of Florida, Gainesville, Florida 32611; e-mail:
| |
Collapse
|
45
|
Cerling TE, Harris JM, Ambrose SH, Leakey MG, Solounias N. Dietary and environmental reconstruction with stable isotope analyses of herbivore tooth enamel from the Miocene locality of Fort Ternan, Kenya. J Hum Evol 1997; 33:635-50. [PMID: 9467773 DOI: 10.1006/jhev.1997.0151] [Citation(s) in RCA: 133] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Tooth enamel of nine Middle Miocene mammalian herbivores from Fort Ternan, Kenya, was analyzed for delta 13C and delta 18O. The delta 18O values of the tooth enamel compared with pedogenic and diagenetic carbonate confirm the use of stable isotope analysis of fossil tooth enamel as a paleoenvironmental indicator. Furthermore, the delta 18O of tooth enamel indicates differences in water sources between some of the mammals. The delta 13C values of tooth enamel ranged from -8.6(-)-13.0/1000 which is compatible with a pure C3 diet, though the possibility of a small C4 fraction in the diet of a few of the specimens sampled is not precluded. The carbon isotopic data do not support environmental reconstructions of a Serengeti-typed wooded grassland with a significant proportion of C4 grasses. This study does not preclude the presence of C3 grasses at Fort Ternan; it is possible that C3 grasses could have had a wider geographic range if atmospheric CO2 levels were higher than the present values.
Collapse
Affiliation(s)
- T E Cerling
- Department of Geology and Geophysics, University of Utah, Salt Lake City 84103, USA
| | | | | | | | | |
Collapse
|