Investigating the reliability of metapodials as taxonomic Indicators for Beringian horses.
Abstract: The metapodials of extinct horses have long been regarded as one of the most useful skeletal elements to determine taxonomic identity. However, recent research on both extant and extinct horses has revealed the possibility for plasticity in metapodial morphology, leading to notable variability within taxa. This calls into question the reliability of metapodials in species identification, particularly for species identified from fragmentary remains. Here, we use ten measurements of metapodials from 203 specimens of four Pleistocene horse species from eastern Beringia to test whether there are significant differences in metapodial morphology that support the presence of multiple species. We then reconstruct the body masses for every specimen to assess the range in body size within each species and determine whether species differ significantly from one another in mean body mass. We find that that taxonomic groups are based largely on the overall size of the metapodial, and that all metapodial measurements are highly autocorrelated. We also find that mean body mass differs significantly among most, but not all, species. We suggest that metapodial measurements are unreliable taxonomic indicators for Beringian horses given evidence for plasticity in metapodial morphology and their clear reflection of differences in body mass. We recommend future studies use more reliable indicators of taxonomy to identify Beringian horse species, particularly from localities from which fossils of several species have been recovered. Unassigned: The online version contains supplementary material available at 10.1007/s10914-022-09626-4.
© The Author(s) 2022.
Publication Date: 2022-09-21 PubMed ID: 36438779PubMed Central: PMC9684255DOI: 10.1007/s10914-022-09626-4Google Scholar: Lookup
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- Journal Article
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
This research is attempting to verify the reliability of metapodials (long bones in the foot of a horse) as indicators for identifying different extinct horse species in the Beringia region. The study points out that while these skeletal features have been traditionally used for species identification, recent research suggests significant variability within taxa, making such identification difficult and unreliable.
Research Methodology
- The researchers measured the metapodials of 203 specimens from four different extinct horse species found in the eastern Beringia region.
- They studied whether significant differences in metapodial morphology supported the presence of multiple species.
- They reconstructed body masses for all specimens to understand the range in body size within each species and to determine if species significantly differed from one another in average body mass.
Findings
- The research found that taxonomic groups tend to base their classification largely on the overall size of the metapodial.
- However, all metapodial measurements were found to be highly interrelated, or autocorrelated.
- The research also discovered that mean body mass did significantly differ among most, but not all, species.
Recommendations
- Given the finding of significant morphological variability in metapodials that may be mistaken for species difference, the researchers do not consider them reliable taxonomic indicators for extinct Beringian horses.
- They recommend future studies to use more reliable indicators for identifying species, especially in instances where fossils from several different species have been recovered from the same locality.
Cite This Article
APA
Landry Z, Roloson MJ, Fraser D.
(2022).
Investigating the reliability of metapodials as taxonomic Indicators for Beringian horses.
J Mamm Evol, 29(4), 863-875.
https://doi.org/10.1007/s10914-022-09626-4 Publication
Researcher Affiliations
- Department of Earth Sciences, University of Ottawa, 25 Templeton Street, Ottawa, ON K1N 6N5 Canada.
- Beaty Centre for Species Discovery, Canadian Museum of Nature, PO Box 3443, Station D., Ottawa, ON K1P 6P4 Canada.
- Beaty Centre for Species Discovery, Canadian Museum of Nature, PO Box 3443, Station D., Ottawa, ON K1P 6P4 Canada.
- Department of Earth Sciences, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6 Canada.
- Beaty Centre for Species Discovery, Canadian Museum of Nature, PO Box 3443, Station D., Ottawa, ON K1P 6P4 Canada.
- Department of Earth Sciences, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6 Canada.
- Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6 Canada.
- Paleobiology Smithsonian National Museum of Natural History, DC 20560 Washington, USA.
Conflict of Interest Statement
Competing interestsAuthor DF is the Director for the Beaty Centre for Species Discovery and receives a salary from the Canadian Museum of Nature. Author DF is an Associate Editor for the Journal of Mammalian Evolution. The authors have no other competing interests to declare.
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