Evolution of growth strategy in alligators and caimans informed by osteohistology of the late Eocene early‐diverging alligatoroid crocodylian Diplocynodon hantoniensis DOI Creative Commons
Devin K. Hoffman, Erika R. Goldsmith, Alexandra Houssaye

et al.

Journal of Anatomy, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 9, 2025

Among living crocodylians, alligatoroids exhibit a wide range of body sizes and biogeographic distribution that spans tropical-to-subtropical climates. The fossil record alligatoroids, however, reveals even greater diversity, including multiple examples gigantism broader extends into polar latitudes. Osteohistological studies on extant show alligators caimans both seasonal growth, with roughly comparable growth rates. However, diverged from one another over 60 million years ago; the dearth extinct makes it unclear if shared condition in taxa reflects convergent responses to rapid climatic changes recent past or represents ancestral alligatoroids. Additionally, sample are often limited two individuals, especially obscuring any intraspecific variation present. To address this uncertainty, we conducted largest monospecific osteohistological study an crocodylian date, based nine femora, providing unique insight early-diverging alligatoroid Diplocynodon hantoniensis late Eocene UK. bone microanatomy D. shows moderate compactness, well-defined medullary cavity, features generally consistent those Samples vary greatly along continuum degree remodelling vascularity, highlighting importance evaluating limitations basing histological assessments singleton samples. Ontogenetic assessment indicates our captures skeletally immature mature approximately corresponding femoral size, but notable exceptions possibly driven by sexual dimorphism. Body size estimates for (1.2-3.4 m) fall within typical American (Alligator mississippiensis). Reconstruction cyclical marks similar overall rate between A. mississippiensis. As more generally, is determinate, seasonally-controlled growth. Femoral circumference scales positively length hantoniensis, demonstrating allometry This differs some other crocodylians (e.g. Crocodylus niloticus johnstoni) suggests conservation allometric relationships in-depth look early diverging seasonality rates present members were established near base clade. Furthermore, highlights larger samples singular species order capture potential when making clade-wide interpretations.

Language: Английский

Evolution of growth strategy in alligators and caimans informed by osteohistology of the late Eocene early‐diverging alligatoroid crocodylian Diplocynodon hantoniensis DOI Creative Commons
Devin K. Hoffman, Erika R. Goldsmith, Alexandra Houssaye

et al.

Journal of Anatomy, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 9, 2025

Among living crocodylians, alligatoroids exhibit a wide range of body sizes and biogeographic distribution that spans tropical-to-subtropical climates. The fossil record alligatoroids, however, reveals even greater diversity, including multiple examples gigantism broader extends into polar latitudes. Osteohistological studies on extant show alligators caimans both seasonal growth, with roughly comparable growth rates. However, diverged from one another over 60 million years ago; the dearth extinct makes it unclear if shared condition in taxa reflects convergent responses to rapid climatic changes recent past or represents ancestral alligatoroids. Additionally, sample are often limited two individuals, especially obscuring any intraspecific variation present. To address this uncertainty, we conducted largest monospecific osteohistological study an crocodylian date, based nine femora, providing unique insight early-diverging alligatoroid Diplocynodon hantoniensis late Eocene UK. bone microanatomy D. shows moderate compactness, well-defined medullary cavity, features generally consistent those Samples vary greatly along continuum degree remodelling vascularity, highlighting importance evaluating limitations basing histological assessments singleton samples. Ontogenetic assessment indicates our captures skeletally immature mature approximately corresponding femoral size, but notable exceptions possibly driven by sexual dimorphism. Body size estimates for (1.2-3.4 m) fall within typical American (Alligator mississippiensis). Reconstruction cyclical marks similar overall rate between A. mississippiensis. As more generally, is determinate, seasonally-controlled growth. Femoral circumference scales positively length hantoniensis, demonstrating allometry This differs some other crocodylians (e.g. Crocodylus niloticus johnstoni) suggests conservation allometric relationships in-depth look early diverging seasonality rates present members were established near base clade. Furthermore, highlights larger samples singular species order capture potential when making clade-wide interpretations.

Language: Английский

Citations

0