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Bartolini-Lucenti S, Cirilli O, Melchionna M, Raia P, Tseng ZJ, Flynn JJ, Rook L. Virtual reconstruction of the Canis arnensis type (Canidae, Mammalia) from the Upper Valdarno Basin (Italy, Early Pleistocene). Sci Rep 2024; 14:8303. [PMID: 38594298 PMCID: PMC11004169 DOI: 10.1038/s41598-024-53073-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 01/27/2024] [Indexed: 04/11/2024] Open
Abstract
Taphonomic deformation, whether it be brittle or plastic, is possibly the most influential process hindering the correct understanding of fossil species morphology. This is especially true if the deformation affects type specimens or applies to or obscures taxonomically diagnostic or functionally significant traits. Target Deformation, a recently developed virtual manipulation protocol, was implemented to address this issue by applying landmark-guided restoration of the original, deformed fossils, using undeformed specimens (or parts thereof) of the same species as a reference. The enigmatic Early Pleistocene canid Canis arnensis provides a typical example of a fossil species in dire need of virtual restoration. Its lectotype specimen is heavily deformed and none of the few known skulls are well preserved, obscuring the recognition of its systematic and phylogenetic position. Our results indicate that the algorithm effectively countered the lectotype skull's laterolateral compression and its concomitant rostrocaudal elongation. Morphometrically, comparison of the retrodeformed cranium (IGF 867_W) with other specimens of the same species, and to other fossil and extant canid material, confirms IGF 867_W consistently clusters within C. arnensis variability. Overall, the evidence presented here confirms that Target Deformation provides a powerful tool to better characterize complex taxa like C. arnensis, whose knowledge is severely affected by the state of preservation of its fossil material.
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Affiliation(s)
- S Bartolini-Lucenti
- Earth Science Department, Paleo[Fab]Lab, University of Florence, via La Pira 4, 50121, Florence, Italy.
- Institut Català de Paleontologia Miquel Crusafont, Universitat Autònoma de Barcelona, Edifici ICTA-ICP, c/Columnes s/n, Campus de la UAB, 08193, Cerdanyola del Vallès, Spain.
| | - O Cirilli
- Institut Català de Paleontologia Miquel Crusafont, Universitat Autònoma de Barcelona, Edifici ICTA-ICP, c/Columnes s/n, Campus de la UAB, 08193, Cerdanyola del Vallès, Spain
- Laboratory of Evolutionary Biology, Department of Anatomy, College of Medicine, 520 W St. N.W., Washington, DC, 20059, USA
| | - M Melchionna
- Dipartimento di Scienze della Terra, dell'Ambiente e delle Risorse, Università degli Studi di Napoli Federico II, Via Cinthia 21, 80126, Naples, Italy
| | - P Raia
- Dipartimento di Scienze della Terra, dell'Ambiente e delle Risorse, Università degli Studi di Napoli Federico II, Via Cinthia 21, 80126, Naples, Italy
| | - Z J Tseng
- Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, CA, 94720, USA
| | - J J Flynn
- Division of Paleontology, American Museum of Natural History, 200 Central Park West, New York, NY, 10024, USA
| | - L Rook
- Earth Science Department, Paleo[Fab]Lab, University of Florence, via La Pira 4, 50121, Florence, Italy.
- Changes Foundation, Sapienza Università di Roma, Piazzale Aldo Moro 5, 00185, Rome, Italy.
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2
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Tseng ZJ. Bending performance changes during prolonged canine eruption in saber-toothed carnivores: A case study of Smilodon fatalis. Anat Rec (Hoboken) 2024. [PMID: 38588019 DOI: 10.1002/ar.25447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 03/19/2024] [Accepted: 03/19/2024] [Indexed: 04/10/2024]
Abstract
The canine of saber-toothed predators represents one of the most specialized dental structures known. Hypotheses about the function of hypertrophied canines range from display and conspecific interaction, soft food processing, to active prey acquisition. Recent research on the ontogenetic timing of skull traits indicates the adult canine can take years to fully erupt, but the consequences of prolonged eruption on inferences of canine functional morphology are missing from current discourse and have not been quantified. Here I evaluate hypotheses about adult canine bending strength and stiffness, respectively, during eruption in the felid Smilodon fatalis. Simulated eruption sequences of three adult canines were generated from specimen models to assess shifting cross-sectional geometry properties, and bending strength and stiffness under laterally directed loads were estimated using finite element analysis. Consistent with beam theory expectations, S. fatalis canine cross-sectional geometry is optimized for increased bending strength with increased erupted height. However, canine cross-sectional geometry changes through eruption exaggerate rather than minimize lateral deflection. Spatial constraint for maximum root length from adjacent sensory structures in the maxilla and the recently identified universal power law are hypothesized to limit the growth capacity of canine anteroposterior length and, consequently, maintenance of bending stiffness through eruption. Instead, the joint presence of the deciduous and adult canines for >50% of the adult canine eruption period effectively increases canine mediolateral width and brings bending strength and stiffness estimates closer to theoretical optima. Similarly prolonged retention of deciduous canines in other sabertooths suggests dual-canine buttressing is a convergently evolved strategy to maximize bending strength and stiffness.
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Affiliation(s)
- Z Jack Tseng
- Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, California, USA
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3
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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4
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Fostowicz-Frelik Ł, Tseng ZJ. The mammalian skull: development, structure and function. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220077. [PMID: 37183895 PMCID: PMC10184243 DOI: 10.1098/rstb.2022.0077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023] Open
Abstract
The mammalian skull is an informative and versatile study system critical to research efforts across the broad spectrum of molecular, cellular, organismal and evolutionary sciences. The amount of knowledge concerning mammalian skull continues to grow exponentially, fuelled by the advent of new research methods and new material. Computed microtomography, including X-ray imaging using synchrotron radiation, proved to be an important tool for the descriptive and quantitative analysis of cranial anatomy. A major conceptual change, namely combining genetics and development with evolution into 'evo-devo' studies, also contributed to our knowledge of the mammalian skull enormously. These advances, coupled with novel techniques now allow researchers to integrate the process of cranial development with data from the fossil record, which is also augmented by seminal discoveries from Africa, Asia and both Americas. However, for decades, there has been no comprehensive source covering fundamental aspects of this vibrant field of evolutionary biology. To address this gap, we offer in this theme issue a balanced mix of research papers and reviews from leading experts in the field and a younger generation of scientists from five continents. This article is part of the theme issue 'The mammalian skull: development, structure and function'.
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Affiliation(s)
- Łucja Fostowicz-Frelik
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, IL 60637, USA
- Institute of Paleobiology, Polish Academy of Sciences, 00-818 Warsaw, Poland
| | - Z Jack Tseng
- Department of Integrative Biology, University of California, Berkeley, CA 94720-3200, USA
- University of California Museum of Paleontology, Berkeley, CA 94720, USA
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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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] [What about the content of this article? (0)] [Affiliation(s)] [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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8
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Chatar N, Fischer V, Tseng ZJ. Many-to-one function of cat-like mandibles highlights a continuum of sabre-tooth adaptations. Proc Biol Sci 2022; 289:20221627. [PMID: 36475442 PMCID: PMC9727663 DOI: 10.1098/rspb.2022.1627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Cat-like carnivorans are a textbook example of convergent evolution, with distinct morphological differences between taxa with short or elongated upper canines, the latter often being interpreted as an adaptation to bite at large angles and subdue large prey. This interpretation of the sabre-tooth condition is reinforced by a reduced taxonomic sampling in some studies, often focusing on highly derived taxa or using simplified morphological models. Moreover, most biomechanical analyses focus on biting scenarios at small gapes, ideal for modern carnivora but ill-suited to test for subduction of large prey by sabre-toothed taxa. In this contribution, we present the largest three-dimensional collection-based muscle-induced biting simulations on cat-like carnivorans by running a total of 1074 analyses on 17 different taxa at three different biting angles (30°, 60° and 90°) including both morphologies. While our results show a clear adaptation of extreme sabre-toothed taxa to bite at larger angles in terms of stress distribution, other performance variables display surprising similarities between all forms at the different angles tested, highlighting a continuous rather than bipolar spectrum of hunting methods in cat-like carnivorans and demonstrating a wide functional disparity and nuances of the sabre-tooth condition that cannot simply be characterized by specialized feeding biomechanics.
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Affiliation(s)
- Narimane Chatar
- Evolution and Diversity Dynamics lab, UR Geology, Université de Liège, Building B18, Quartier Agora, Allée du Six Août 14, Liège, 4000, Belgium
| | - Valentin Fischer
- Evolution and Diversity Dynamics lab, UR Geology, Université de Liège, Building B18, Quartier Agora, Allée du Six Août 14, Liège, 4000, Belgium
| | - Z. Jack Tseng
- Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, CA 94720, USA
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Wang X, Li Q, Tseng ZJ. Primitive Tibetan antelope, Qurliqnoria hundesiensis (Lydekker, 1881) (Bovidae, Artiodactyla), from Pliocene Zanda and Kunlun Pass basins and paleoenvironmental implications. J MAMM EVOL 2022. [DOI: 10.1007/s10914-022-09632-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Bertrand OC, Shelley SL, Williamson TE, Wible JR, Chester SGB, Flynn JJ, Holbrook LT, Lyson TR, Meng J, Miller IM, Püschel HP, Smith T, Spaulding M, Tseng ZJ, Brusatte SL. Brawn before brains in placental mammals after the end-Cretaceous extinction. Science 2022; 376:80-85. [PMID: 35357913 DOI: 10.1126/science.abl5584] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Mammals are the most encephalized vertebrates, with the largest brains relative to body size. Placental mammals have particularly enlarged brains, with expanded neocortices for sensory integration, the origins of which are unclear. We used computed tomography scans of newly discovered Paleocene fossils to show that contrary to the convention that mammal brains have steadily enlarged over time, early placentals initially decreased their relative brain sizes because body mass increased at a faster rate. Later in the Eocene, multiple crown lineages independently acquired highly encephalized brains through marked growth in sensory regions. We argue that the placental radiation initially emphasized increases in body size as extinction survivors filled vacant niches. Brains eventually became larger as ecosystems saturated and competition intensified.
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Affiliation(s)
- Ornella C Bertrand
- School of GeoSciences, University of Edinburgh, Grant Institute, Edinburgh, Scotland EH9 3FE, UK
| | - Sarah L Shelley
- School of GeoSciences, University of Edinburgh, Grant Institute, Edinburgh, Scotland EH9 3FE, UK.,Section of Mammals, Carnegie Museum of Natural History, Pittsburgh, PA, USA
| | | | - John R Wible
- Section of Mammals, Carnegie Museum of Natural History, Pittsburgh, PA, USA
| | - Stephen G B Chester
- Department of Anthropology, Brooklyn College, City University of New York, Brooklyn, NY, USA.,Department of Anthropology, The Graduate Center, City University of New York, New York, NY, USA.,New York Consortium in Evolutionary Primatology, New York, NY, USA
| | - John J Flynn
- Division of Paleontology, American Museum of Natural History, New York, NY, USA.,Department of Earth and Environmental Sciences, Columbia University, New York, NY, USA.,Ecology, Evolutionary Biology, and Behavior subprogram, PhD Program in Biology, The Graduate Center, City University of New York, New York, NY, USA.,PhD Program in Earth and Environmental Sciences, The Graduate Center, City University of New York, New York, NY, USA
| | - Luke T Holbrook
- Department of Biological Sciences, Rowan University, Glassboro, NJ, USA
| | | | - Jin Meng
- Division of Paleontology, American Museum of Natural History, New York, NY, USA
| | - Ian M Miller
- Denver Museum of Nature & Science, Denver, CO, USA.,National Geographic Society, Washington, DC, USA
| | - Hans P Püschel
- School of GeoSciences, University of Edinburgh, Grant Institute, Edinburgh, Scotland EH9 3FE, UK
| | - Thierry Smith
- Directorate Earth and History of Life, Royal Belgian Institute of Natural Sciences, Brussels, Belgium
| | - Michelle Spaulding
- Department of Biological Sciences, Purdue University Northwest, Westville, IN, USA
| | - Z Jack Tseng
- Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, CA, USA
| | - Stephen L Brusatte
- School of GeoSciences, University of Edinburgh, Grant Institute, Edinburgh, Scotland EH9 3FE, UK.,New Mexico Museum of Natural History and Science, Albuquerque, NM, USA
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Tseng ZJ, Wang X, Li Q, Xie G. Qurliqnoria (Mammalia: Bovidae) fossils from Qaidam Basin, Tibetan Plateau and deep-time endemism of the Tibetan antelope lineage. Zool J Linn Soc 2022. [DOI: 10.1093/zoolinnean/zlab117] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
The Tibetan antelope (Pantholops hodgsonii) is an endemic bovid of the Tibetan Plateau, which was, until recently, considered an endangered species. Researchers have long speculated on the evolutionary origin of Pantholops, suggesting a connection to the rare fossil bovid Qurliqnoria. However, the lack of adequate fossil samples has prevented the testing of this deep-time endemism hypothesis for eight decades. Here, we report new fossils of Qurliqnoria cheni from the northern Tibetan Plateau, substantially increasing the amount of morphological data that can be brought to bear on the question of Tibetan antelope evolution. Phylogenetic analysis supports a Pantholops–Qurliqnoria clade and suggests that this lineage has been endemic to the Plateau for 11 Myr. Recent morphological and molecular studies that support the outgroup position of Pantholops relative to caprins (goats and relatives) and the fossil record of stem bovids from Europe together suggest that the Qurliqnoria–Pantholops lineage is likely to have dispersed to the Tibetan Plateau 15–11 Mya. Furthermore, the harsh environmental conditions to which Pantholops has adapted are likely to extend back to the time of its evolutionary origin. These findings provide an important new context for conservation management and research into the near-threatened Tibetan antelope, as the longest-living endemic member of the Tibetan Plateau fauna.
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Affiliation(s)
- Z Jack Tseng
- Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, CA 94720, California, USA
- Department of Vertebrate Paleontology, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007, California, USA
| | - Xiaoming Wang
- Department of Vertebrate Paleontology, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007, California, USA
- Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijng 100044, China
| | - Qiang Li
- Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijng 100044, China
- CAS Center for Excellence in Life and Paleoenvironment, Beijing 100044, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Guangpu Xie
- Natural Science Department, Gansu Provincial Museum, No. 3 Xijingxi Road, Lanzhou 730050, Gansu, China
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12
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Tseng ZJ. Polar bear diet in the face of Arctic climate change. Glob Chang Biol 2021; 27:3004-3005. [PMID: 33735467 DOI: 10.1111/gcb.15599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 03/12/2021] [Indexed: 06/12/2023]
Affiliation(s)
- Z Jack Tseng
- Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, CA, USA
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13
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Peterson JE, Tseng ZJ, Brink S. Bite force estimates in juvenile Tyrannosaurus rex based on simulated puncture marks. PeerJ 2021; 9:e11450. [PMID: 34141468 PMCID: PMC8179241 DOI: 10.7717/peerj.11450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 04/22/2021] [Indexed: 11/20/2022] Open
Abstract
Background Bite marks attributed to adult Tyrannosaurus rex have been subject to numerous studies. However, few bite marks attributed to T. rex have been traced to juveniles, leaving considerable gaps in understanding ontogenetic changes in bite mechanics and force, and the paleoecological role of juvenile tyrannosaurs in the late Cretaceous. Methods Here we present bite force estimates for a juvenile Tyrannosaurus rex based on mechanical tests designed to replicate bite marks previously attributed to a T. rex of approximately 13 years old. A maxillary tooth of the juvenile Tyrannosaurus specimen BMR P2002.4.1 was digitized, replicated in dental grade cobalt chromium alloy, and mounted to an electromechanical testing system. The tooth was then pressed into bovine long bones in various locations with differing cortical bone thicknesses at varying speeds for a total of 17 trials. Forces required to replicate punctures were recorded and puncture dimensions were measured. Results Our experimentally derived linear models suggest bite forces up to 5,641.19 N from cortical bone thickness estimated from puncture marks on an Edmontosaurus and a juvenile Tyrannosaurus. These findings are slightly higher than previously estimated bite forces for a juvenile Tyrannosaurus rex of approximately the same size as BMR P2002.4.1 but fall within the expected range when compared to estimates of adult T. rex. Discussion The results of this study offer further insight into the role of juvenile tyrannosaurs in late Cretaceous ecosystems. Furthermore, we discuss the implications for feeding mechanisms, feeding behaviors, and ontogenetic niche partitioning.
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Affiliation(s)
- Joseph E Peterson
- Department of Geology, University of Wisconsin Oshkosh, Oshkosh, Wisconsin, United States of America
| | - Z Jack Tseng
- Department of Integrative Biology and Museum of Paleontology, University of California Berkeley, Berkeley, California, United States of America
| | - Shannon Brink
- Department of Geological Sciences, East Carolina University, Greenville, North Carolina, United States of America
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Abstract
In the past 15 years, the finite element (FE) method has become a ubiquitous tool in the repertoire of evolutionary biologists. The method is used to estimate and compare biomechanical performance implicated as selective factors in the evolution of morphological structures. A feature common to many comparative studies using 3D FE simulations is small taxonomic sample sizes. The time-consuming nature of FE model construction is considered a main limiting factor in taxonomic breadth of comparative FE analyses. Using a composite FE model dataset, I show that the combination of small taxonomic sample sizes and comparative FE data in analyses of evolutionary associations of biomechanical performance to feeding ecology generates artificially elevated correlations. Such biases introduce false positives into interpretations of clade-level trends. Considering this potential pitfall, recommendations are provided to consider the ways FE analyses are best used to address both taxon-specific and clade-level evolutionary questions.
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Affiliation(s)
- Z Jack Tseng
- Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, CA, USA
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15
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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. Sci Adv 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] [What about the content of this article? (0)] [Affiliation(s)] [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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16
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Santaella BL, Tseng ZJ. Hole in One: an element reduction approach to modeling bone porosity in finite element analysis. PeerJ 2019; 7:e8112. [PMID: 31875143 PMCID: PMC6925947 DOI: 10.7717/peerj.8112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 10/28/2019] [Indexed: 11/20/2022] Open
Abstract
Finite element analysis has been an increasingly widely applied biomechanical modeling method in many different science and engineering fields over the last decade. In the biological sciences, there are many examples of FEA in areas such as paleontology and functional morphology. Despite this common use, the modeling of trabecular bone remains a key issue because their highly complex and porous geometries are difficult to replicate in the solid mesh format required for many simulations. A common practice is to assign uniform model material properties to whole or portions of models that represent trabecular bone. In this study we aimed to demonstrate that a physical, element reduction approach constitutes a valid protocol for addressing this problem in addition to the wholesale mathematical approach. We tested a customized script for element reduction modeling on five exemplar trabecular geometry models of carnivoran temporomandibular joints, and compared stress and strain energy results of both physical and mathematical trabecular modeling to models incorporating actual trabecular geometry. Simulation results indicate that that the physical, element reduction approach generally outperformed the mathematical approach: physical changes in the internal structure of experimental cylindrical models had a major influence on the recorded stress values throughout the model, and more closely approximates values obtained in models containing actual trabecular geometry than solid models with modified trabecular material properties. In models with both physical and mathematical adjustments for bone porosity, the physical changes exhibit more weight than material properties changes in approximating values of control models. Therefore, we conclude that maintaining or mimicking the internal porosity of a trabecular structure is a more effective method of approximating trabecular bone behavior in finite element models than modifying material properties.
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Affiliation(s)
- Beatriz L Santaella
- Department of Pathology and Anatomical Sciences, Jacobs School of Medicine and Biomedical Sciences, State University of New York, Buffalo, NY, United States of America
| | - Z Jack Tseng
- Department of Pathology and Anatomical Sciences, Jacobs School of Medicine and Biomedical Sciences, State University of New York, Buffalo, NY, United States of America.,Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, CA, United States of America.,Division of Paleontology, American Museum of Natural History, New York, NY, United States of America
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17
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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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18
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Wang X, White SC, Balisi M, Biewer J, Sankey J, Garber D, Tseng ZJ. First bone-cracking dog coprolites provide new insight into bone consumption in Borophagus and their unique ecological niche. eLife 2018; 7:34773. [PMID: 29785931 PMCID: PMC5963924 DOI: 10.7554/elife.34773] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 04/16/2018] [Indexed: 11/13/2022] Open
Abstract
Borophagine canids have long been hypothesized to be North American ecological 'avatars' of living hyenas in Africa and Asia, but direct fossil evidence of hyena-like bone consumption is hitherto unknown. We report rare coprolites (fossilized feces) of Borophagus parvus from the late Miocene of California and, for the first time, describe unambiguous evidence that these predatory canids ingested large amounts of bone. Surface morphology, micro-CT analyses, and contextual information reveal (1) droppings in concentrations signifying scent-marking behavior, similar to latrines used by living social carnivorans; (2) routine consumption of skeletons; (3) undissolved bones inside coprolites indicating gastrointestinal similarity to modern striped and brown hyenas; (4) B. parvus body weight of ~24 kg, reaching sizes of obligatory large-prey hunters; and (5) prey size ranging ~35-100 kg. This combination of traits suggests that bone-crushing Borophagus potentially hunted in collaborative social groups and occupied a niche no longer present in North American ecosystems.
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Affiliation(s)
- Xiaoming Wang
- Department of Vertebrate Paleontology, Natural History Museum of Los Angeles County, Los Angeles, United States.,Department of Vertebrate Paleontology, American Museum of Natural History, New York, United States.,Department of Ecology and Evolutionary Biology, University of California, Los Angeles, United States
| | - Stuart C White
- School of Dentistry, University of California, Los Angeles, United States
| | - Mairin Balisi
- Department of Vertebrate Paleontology, Natural History Museum of Los Angeles County, Los Angeles, United States.,Department of Ecology and Evolutionary Biology, University of California, Los Angeles, United States
| | - Jacob Biewer
- Department of Geological Sciences, California State University, Fullerton, United States.,Department of Geology, California State University Stanislaus, Turlock, United States
| | - Julia Sankey
- Department of Geology, California State University Stanislaus, Turlock, United States
| | - Dennis Garber
- Department of Vertebrate Paleontology, Natural History Museum of Los Angeles County, Los Angeles, United States
| | - Z Jack Tseng
- Department of Vertebrate Paleontology, Natural History Museum of Los Angeles County, Los Angeles, United States.,Department of Vertebrate Paleontology, American Museum of Natural History, New York, United States.,Department of Pathology and Anatomical Sciences, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, United States
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19
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Tseng ZJ, Flynn JJ. Structure-function covariation with nonfeeding ecological variables influences evolution of feeding specialization in Carnivora. Sci Adv 2018; 4:eaao5441. [PMID: 29441363 PMCID: PMC5810607 DOI: 10.1126/sciadv.aao5441] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 01/08/2018] [Indexed: 05/06/2023]
Abstract
Skull shape convergence is pervasive among vertebrates. Although this is frequently inferred to indicate similar functional underpinnings, neither the specific structure-function linkages nor the selective environments in which the supposed functional adaptations arose are commonly identified and tested. We demonstrate that nonfeeding factors relating to sexual maturity and precipitation-related arboreality also can generate structure-function relationships in the skulls of carnivorans (dogs, cats, seals, and relatives) through covariation with masticatory performance. We estimated measures of masticatory performance related to ecological variables that covary with cranial shape in the mammalian order Carnivora, integrating geometric morphometrics and finite element analyses. Even after accounting for phylogenetic autocorrelation, cranial shapes are significantly correlated to both feeding and nonfeeding ecological variables, and covariation with both variable types generated significant masticatory performance gradients. This suggests that mechanisms of obligate shape covariation with nonfeeding variables can produce performance changes resembling those arising from feeding adaptations in Carnivora.
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Affiliation(s)
- Z. Jack Tseng
- Department of Pathology and Anatomical Sciences, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14203, USA
- Division of Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA
- Corresponding author.
| | - John J. Flynn
- Division of Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA
- Richard Gilder Graduate School, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA
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20
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Tseng ZJ, Su DF, Wang X, White SC, Ji X. Feeding capability in the extinct giant Siamogale melilutra and comparative mandibular biomechanics of living Lutrinae. Sci Rep 2017; 7:15225. [PMID: 29123190 PMCID: PMC5680181 DOI: 10.1038/s41598-017-15391-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 10/26/2017] [Indexed: 11/09/2022] Open
Abstract
At 50 kg in estimated weight, the extinct Siamogale melilutra is larger than all living otters, and ranks among the largest fossil otters. The biomechanical capability of S. melilutra jaws as related to their large size is unknown but crucial to reconstructing the species' potentially unique ecological niche. Here we compare the mandibular biomechanics of S. melilutra using engineering-based performance measures against ten extant otter biomechanical models. Despite a wide range of feeding preferences from durophagy to piscivory, living otter species exhibit a linear relationship between mandible stiffness and volume, as expected in isometric model scaling. In contrast, S. melilutra models exhibit a six-fold increase in stiffness from expected stiffness-volume relationships calculated from extant species models. Unlike stiffness, mechanical efficiency of biting is conserved among living otters and in S. melilutra. These findings indicate that although similar to living bunodont otters in morphology and biting efficiency, jaw strength in S. melilutra far surpasses molluscivores such as sea otters and Cape clawless otters, even after accounting for size. Therefore, Siamogale represents a feeding ecomorphology with no living analog, and its giant size and high mandibular strength confer shell-crushing capability matched only by other extinct molluscivores such as the marine bear Kolponomos.
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Affiliation(s)
- Z Jack Tseng
- Department of Pathology and Anatomical Sciences, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York, 14214, USA. .,Division of Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, New York 10024, USA. .,Department of Vertebrate Paleontology, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, California, 90007, USA.
| | - Denise F Su
- Department of Paleobotany and Paleoecology, Cleveland Museum of Natural History, 1 Wade Oval Drive, University Circle, Cleveland, Ohio, 44106, USA
| | - Xiaoming Wang
- Division of Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, New York 10024, USA.,Department of Vertebrate Paleontology, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, California, 90007, USA.,Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, 100044, China
| | - Stuart C White
- School of Dentistry, University of California, Los Angeles, 10833 Le Conte Ave., Los Angeles, California, 90095, USA
| | - Xueping Ji
- Yunnan Institute of Cultural Relics and Archaeology, 15-1, Chunmingli, Chunyuan Xiaoqu, Kunming, Yunnan, 650118, China
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21
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Tseng ZJ, Pacheco-Castro A, Carranza-Castañeda O, Aranda-Gómez JJ, Wang X, Troncoso H. Discovery of the fossil otter Enhydritherium terraenovae (Carnivora, Mammalia) in Mexico reconciles a palaeozoogeographic mystery. Biol Lett 2017; 13:rsbl.2017.0259. [PMID: 28615353 DOI: 10.1098/rsbl.2017.0259] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Accepted: 05/23/2017] [Indexed: 11/12/2022] Open
Abstract
The North American fossil otter Enhydritherium terraenovae is thought to be partially convergent in ecological niche with the living sea otter Enhydra lutris, both having low-crowned crushing teeth and a close association with marine environments. Fossil records of Enhydritherium are found in mostly marginal marine deposits in California and Florida; despite presence of very rich records of fossil terrestrial mammals in contemporaneous localities inland, no Enhydritherium fossils are hitherto known in interior North America. Here we report the first occurrence of Enhydritherium outside of Florida and California, in a land-locked terrestrial mammal fauna of the upper Miocene deposits of Juchipila Basin, Zacatecas State, Mexico. This new occurrence of Enhydritherium is at least 200 km from the modern Pacific coastline, and nearly 600 km from the Gulf of Mexico. Besides providing further evidence that Enhydritherium was not dependent on coastal marine environments as originally interpreted, this discovery leads us to propose a new east-to-west dispersal route between the Florida and California Enhydritherium populations through central Mexico. The proximity of the fossil locality to nearby populations of modern neotropical otters Lontra longicaudis suggests that trans-Mexican freshwater corridors for vertebrate species in riparian habitats may have persisted for a prolonged period of time, pre-dating the Great American Biotic Interchange.
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Affiliation(s)
- Z Jack Tseng
- Department of Pathology and Anatomical Sciences, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14214, USA .,Department of Vertebrate Paleontology, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007, USA.,Division of Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA
| | - Adolfo Pacheco-Castro
- Centro de Geociencias, Universidad Nacional Autónoma de México, Boulevard Juriquilla 3001, Juriquilla, Querétaro 76230, Mexico
| | - Oscar Carranza-Castañeda
- Centro de Geociencias, Universidad Nacional Autónoma de México, Boulevard Juriquilla 3001, Juriquilla, Querétaro 76230, Mexico
| | - José Jorge Aranda-Gómez
- Centro de Geociencias, Universidad Nacional Autónoma de México, Boulevard Juriquilla 3001, Juriquilla, Querétaro 76230, Mexico
| | - Xiaoming Wang
- Department of Vertebrate Paleontology, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007, USA.,Division of Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA
| | - Hilda Troncoso
- Centro de Geociencias, Universidad Nacional Autónoma de México, Boulevard Juriquilla 3001, Juriquilla, Querétaro 76230, Mexico
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22
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Tseng ZJ, Grohé C, Flynn JJ. A unique feeding strategy of the extinct marine mammal Kolponomos: convergence on sabretooths and sea otters. Proc Biol Sci 2016; 283:20160044. [PMID: 26936242 DOI: 10.1098/rspb.2016.0044] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Mammalian molluscivores feed mainly by shell-crushing or suction-feeding. The extinct marine arctoid, Kolponomos, has been interpreted as an otter-like shell-crusher based on similar dentitions. However, neither the masticatory biomechanics of the shell-crushing adaptation nor the way Kolponomos may have captured hard-shelled prey have been tested. Based on mandibular symphyseal morphology shared by Kolponomos and sabre-toothed carnivores, we hypothesize a sabretooth-like mechanism for Kolponomos prey-capture, whereby the mandible functioned as an anchor. Torque generated from jaw closure and head flexion was used to dislodge prey by prying, with prey then crushed using cheek teeth. We test this hypothesized feeding sequence using phylogenetically informed biomechanical simulations and shape analyses, and find a strongly supported, shared high mandibular stiffness in simulated prey-capture bites and mandibular shape in Kolponomos and the sabre-toothed cat Smilodon. These two distantly related taxa converged on using mandibles to anchor cranial torqueing forces when prying substrate-bound prey in the former and sabre-driving forces during prey-killing in the latter. Simulated prey-crushing bites indicate that Kolponomos and sea otters exhibit alternative structural stiffness-bite efficiency combinations in mandibular biomechanical adaptation for shell-crushing. This unique feeding system of Kolponomos exemplifies a mosaic of form-function convergence relative to other Carnivora.
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Affiliation(s)
- Z Jack Tseng
- Division of Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA
| | - Camille Grohé
- Division of Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA
| | - John J Flynn
- Division of Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA Richard Gilder Graduate School, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA
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23
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Tseng ZJ, Flynn JJ. An integrative method for testing form-function linkages and reconstructed evolutionary pathways of masticatory specialization. J R Soc Interface 2016; 12:rsif.2015.0184. [PMID: 25994295 DOI: 10.1098/rsif.2015.0184] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Morphology serves as a ubiquitous proxy in macroevolutionary studies to identify potential adaptive processes and patterns. Inferences of functional significance of phenotypes or their evolution are overwhelmingly based on data from living taxa. Yet, correspondence between form and function has been tested in only a few model species, and those linkages are highly complex. The lack of explicit methodologies to integrate form and function analyses within a deep-time and phylogenetic context weakens inferences of adaptive morphological evolution, by invoking but not testing form-function linkages. Here, we provide a novel approach to test mechanical properties at reconstructed ancestral nodes/taxa and the strength and direction of evolutionary pathways in feeding biomechanics, in a case study of carnivorous mammals. Using biomechanical profile comparisons that provide functional signals for the separation of feeding morphologies, we demonstrate, using experimental optimization criteria on estimation of strength and direction of functional changes on a phylogeny, that convergence in mechanical properties and degree of evolutionary optimization can be decoupled. This integrative approach is broadly applicable to other clades, by using quantitative data and model-based tests to evaluate interpretations of function from morphology and functional explanations for observed macroevolutionary pathways.
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Affiliation(s)
- Z Jack Tseng
- Division of Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA
| | - John J Flynn
- Division of Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA Richard Gilder Graduate School, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA
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Grohé C, Tseng ZJ, Lebrun R, Boistel R, Flynn JJ. Bony labyrinth shape variation in extant Carnivora: a case study of Musteloidea. J Anat 2015; 228:366-83. [PMID: 26577069 DOI: 10.1111/joa.12421] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/25/2015] [Indexed: 02/06/2023] Open
Abstract
The bony labyrinth provides a proxy for the morphology of the inner ear, a primary cognitive organ involved in hearing, body perception in space, and balance in vertebrates. Bony labyrinth shape variations often are attributed to phylogenetic and ecological factors. Here we use three-dimensional (3D) geometric morphometrics to examine the phylogenetic and ecological patterns of variation in the bony labyrinth morphology of the most species-rich and ecologically diversified traditionally recognized superfamily of Carnivora, the Musteloidea (e.g. weasels, otters, badgers, red panda, skunks, raccoons, coatis). We scanned the basicrania of specimens belonging to 31 species using high-resolution X-ray computed micro-tomography (μCT) to virtually reconstruct 3D models of the bony labyrinths. Labyrinth morphology is captured by a set of six fixed landmarks on the vestibular and cochlear systems, and 120 sliding semilandmarks, slid at the center of the semicircular canals and the cochlea. We found that the morphology of this sensory structure is not significantly influenced by bony labyrinth size, in comparisons across all musteloids or in any of the individual traditionally recognized families (Mephitidae, Procyonidae, Mustelidae). PCA (principal components analysis) of shape data revealed that bony labyrinth morphology is clearly distinguishable between musteloid families, and permutation tests of the Kmult statistic confirmed that the bony labyrinth shows a phylogenetic signal in musteloids and in most mustelids. Both the vestibular and cochlear regions display morphological differences among the musteloids sampled, associated with the size and curvature of the semicircular canals, angles between canals, presence or absence of a secondary common crus, degree of lateral compression of the vestibule, orientation of the cochlea relative to the semicircular canals, proportions of the cochlea, and degree of curvature of its turns. We detected a significant ecological signal in the bony labyrinth shape of musteloids, differentiating semi-aquatic taxa from non-aquatic ones (the taxa assigned to terrestrial, arboreal, semi-arboreal, and semi-fossorial categories), and a significant signal for mustelids, differentiating the bony labyrinths of terrestrial, semi-arboreal, arboreal, semi-fossorial and semi-aquatic species from each other. Otters and minks are distinguished from non-aquatic musteloids by an oval rather than circular anterior canal, sinuous rather than straight lateral canal, and acute rather than straight angle between the posterior and lateral semicircular canals - each of these morphological characters has been related previously to animal sensitivity for detecting head motion in space.
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Affiliation(s)
- Camille Grohé
- Division of Paleontology, American Museum of Natural History, New York, NY, USA.,Institut des Sciences de l'Évolution de Montpellier (ISE-M UMR-CNRS 5554) - Université Montpellier II, Montpellier, France
| | - Z Jack Tseng
- Division of Paleontology, American Museum of Natural History, New York, NY, USA
| | - Renaud Lebrun
- Institut des Sciences de l'Évolution de Montpellier (ISE-M UMR-CNRS 5554) - Université Montpellier II, Montpellier, France
| | - Renaud Boistel
- Institut de Paléoprimatologie, Paléontologie Humaine: Évolution et Paléoenvironnements (IPHEP UMR-CNRS 7262) - Université de Poitiers, Poitiers, France
| | - John J Flynn
- Division of Paleontology, American Museum of Natural History, New York, NY, USA.,Richard Gilder Graduate School, American Museum of Natural History, New York, NY, USA
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25
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Tseng ZJ, Wang X, Slater GJ, Takeuchi GT, Li Q, Liu J, Xie G. Himalayan fossils of the oldest known pantherine establish ancient origin of big cats. Proc Biol Sci 2014; 281:20132686. [PMID: 24225466 PMCID: PMC3843846 DOI: 10.1098/rspb.2013.2686] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 10/18/2013] [Indexed: 11/12/2022] Open
Abstract
Pantherine felids ('big cats') include the largest living cats, apex predators in their respective ecosystems. They are also the earliest diverging living cat lineage, and thus are important for understanding the evolution of all subsequent felid groups. Although the oldest pantherine fossils occur in Africa, molecular phylogenies point to Asia as their region of origin. This paradox cannot be reconciled using current knowledge, mainly because early big cat fossils are exceedingly rare and fragmentary. Here, we report the discovery of a fossil pantherine from the Tibetan Himalaya, with an age of Late Miocene-Early Pliocene, replacing African records as the oldest pantherine. A 'total evidence' phylogenetic analysis of pantherines indicates that the new cat is closely related to the snow leopard and exhibits intermediate characteristics on the evolutionary line to the largest cats. Historical biogeographic models provide robust support for the Asian origin of pantherines. The combined analyses indicate that 75% of the divergence events in the pantherine lineage extended back to the Miocene, up to 7 Myr earlier than previously estimated. The deeper evolutionary origin of big cats revealed by the new fossils and analyses indicate a close association between Tibetan Plateau uplift and diversification of the earliest living cats.
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Affiliation(s)
- Z. Jack Tseng
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
- Department of Vertebrate Paleontology, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007, USA
- Division of Paleontology, American Museum of Natural History, New York, NY 10024, USA
| | - Xiaoming Wang
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
- Department of Vertebrate Paleontology, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007, USA
- Division of Paleontology, American Museum of Natural History, New York, NY 10024, USA
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, People's Republic of China
| | - Graham J. Slater
- Department of Paleobiology and Division of Mammals, National Museum of Natural History, The Smithsonian Institution (NHB, MRC 121), PO Box 37012, Washington, DC 20013-7012, USA
| | - Gary T. Takeuchi
- Department of Vertebrate Paleontology, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007, USA
- The George C. Page Museum, 5801 Wilshire Boulevard, Los Angeles, CA 90036, USA
| | - Qiang Li
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, People's Republic of China
| | - Juan Liu
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, People's Republic of China
- Department of Biological Sciences, University of Alberta, Edmonton, CanadaT6G 2E9
| | - Guangpu Xie
- Gansu Provincial Museum, Lanzhou 730050, People's Republic of China
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