TY - JOUR
T1 - Incubation Temperature Modifies Sex Ratio of Hatchlings in Collared Lizards, Crotaphytus collaris
AU - Santoyo-Brito, Enrique
AU - Anderson, Matthew
AU - Fox, Stanley
N1 - Publisher Copyright:
© Copyright 2017 Society for the Study of Amphibians and Reptiles.
PY - 2017/6/1
Y1 - 2017/6/1
N2 - Increasing evidence indicates that sex-determination mechanisms in reptiles (genotypic sex determination GSD and temperature-dependent sex determination TSD) are considerably labile and not mutually exclusive. Environmental factors can override GSD in some reptile species and some species shift from GSD to TSD at certain temperatures. We present data on the effects of incubation temperature on sex ratio in Collared Lizard (Crotaphytus collaris) hatchlings. Eggs were incubated at one of seven constant temperatures. More males were produced at both lower and higher temperatures and more females at intermediate temperatures. Although none of the seven treatments produced only females or only males (nor even differed significantly from an equal sex ratio), incubation at different constant temperatures influenced hatchling sex ratios and produced an overall statistically significant pattern, consistent with TSD pattern II but in an inverse way. Even with a lack of evidence, GSD has been suggested as the sex-determining mechanism in the species. Our results suggest that sex ratio is modified in a consistent pattern depending on incubation temperature; therefore, labeling this species GSD is premature. More research is needed, however, to conclude that C. collaris is a TSD species or a GSD species with temperature interacting with genetic factors.
AB - Increasing evidence indicates that sex-determination mechanisms in reptiles (genotypic sex determination GSD and temperature-dependent sex determination TSD) are considerably labile and not mutually exclusive. Environmental factors can override GSD in some reptile species and some species shift from GSD to TSD at certain temperatures. We present data on the effects of incubation temperature on sex ratio in Collared Lizard (Crotaphytus collaris) hatchlings. Eggs were incubated at one of seven constant temperatures. More males were produced at both lower and higher temperatures and more females at intermediate temperatures. Although none of the seven treatments produced only females or only males (nor even differed significantly from an equal sex ratio), incubation at different constant temperatures influenced hatchling sex ratios and produced an overall statistically significant pattern, consistent with TSD pattern II but in an inverse way. Even with a lack of evidence, GSD has been suggested as the sex-determining mechanism in the species. Our results suggest that sex ratio is modified in a consistent pattern depending on incubation temperature; therefore, labeling this species GSD is premature. More research is needed, however, to conclude that C. collaris is a TSD species or a GSD species with temperature interacting with genetic factors.
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U2 - 10.1670/15-167
DO - 10.1670/15-167
M3 - Article
AN - SCOPUS:85010046566
SN - 0022-1511
VL - 51
SP - 197
EP - 201
JO - Journal of Herpetology
JF - Journal of Herpetology
IS - 2
ER -