Reconstructing the body sizes of Quaternary lizards using Pholidoscelis Fitzinger, 1843, and Anolis Daudin, 1802, as case studies

ABSTRACT

Estimating the size of fossil organisms is essential for most paleontological studies, including studies of fossil squamates. Paradoxically, few works about the methods used to achieve this goal have been published. This study focuses on two genera of lizards found in the Lesser Antilles: Pholidoscelis and Anolis. We produced sets of size estimation equations based on skeletal measurements taken on modern specimens. We tested the effect of the anatomical part used and of the species composition of the comparative sample in order to produce reliable and statistically significant equations. We then compared our results with previously published estimates of fossil size for Anolis lizards. We found that past studies were inconsistent with each other in how body size was estimated even if the same value for a measurement was obtained independently. Further, we found that what others have described as Holocene dwarfism for Anolis bimaculatus is likely to reflect a methodological bias, and fossil representatives of this species likely had a similar size to modern individuals. Many conclusions made in previous studies could not be challenged, however, because even though body size estimates are given, the actual measurements made on skeletal elements remain largely unreported in the literature. These results show that more transparency and reproducibility are needed for studies concerning the body size of fossil squamates.

Citation for this article: Bochaton, C., and M. E. Kemp 2016. Reconstructing the body sizes of Quaternary lizards using Pholidoscelis Fitzinger, 1843, and Anolis Daudin, 1802, as case studies. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2017.1239626.

ACKNOWLEDGMENTS

We are first grateful to all institutions and curators who allow us to access the specimens stored in their collections: Muséum national d'Histoire naturelle (S. Bailon and S. Grouard), National Museum of Natural History (K. de Queiroz), Museum of Comparative Zoology (J. P. Rosado), PACEA laboratory and BIVAAG project (A. Lenoble), and Edgar Clerc Museum (S. Guimaraes). We also thank I. Ineich and E. Hadly for their help in the administrative aspects of this work and G. K. Pregill for his useful advice regarding available comparative specimens. Finally, we thank the editor Jack Conrad and the two anonymous reviewers who helped us improve the quality of this paper.

ORCID

Corentin Bochaton http://orcid.org/0000-0003-4954-0019