SREL Reprint #1022
Skink
Reproduction and Sexual Dimorphism: Eumeces
fasciatus in the Southeastern United States, with Notes on Eumeces
inexpectatus
Laurie
J. Vitt and William E. Cooper, Jr.
Abstract
The morphology and reproductive biology of Eumeces fasciatus
and E. inexpectatus were studied in the southeastern United
States. Eumeces
inexpectatus are slightly larger in body size than E. fasciatus.
Males are larger than females in E. inexpectatus but not in
E. fasciatus. In both
species there is sexual dimorphism in head size (males larger) independent of
body size among sexually mature adults, apparently as a consequence of sexual
selection.
Individuals of both species reach sexual maturity in their
second spring at an age of 21 months. Females
of E. fasciatus lay eggs in nests constructed in hardwood logs,
trees, and stumps, often in proximity to nests of other females.
Eggs deposited in late May and early June are brooded by females and
hatch in late July or early August. Clutches
brooded in the laboratory revealed that eggs increase in mass considerably
during development, but offspring hatch at a size much smaller than eggs at
deposition. In addition, significant differences were found in hatchling
size among clutches. Brooding
behavior and the potential significance of variable offspring size are
discussed.
SREL Reprint #1022
