Some investigators have hypothesized that estrogens and other hormonally active agents
found in the environment might be involved in breast cancer increases and sperm count …

In many vertebrate species, sex is determined at fertilization of zygotes by sex chromosome
composition, knows as genotypic sex determination (GSD). But in some species—fish …

Recent studies suggest that freshwater turtle populations are becoming increasingly male‐
biased. A hypothesized cause is a greater vulnerability of female turtles to road mortality. We …

Cytochrome P450 aromatase (CYP19) is the key steroidogenic enzyme responsible for
conversion of androgens to estrogens which play a critical role in developmental sex …

This book presents a comparative view of chelonian reproduction and discusses
ecophysiological implications for their captive breeding. Chelonians, with their protective …

This book is comprised of 12 chapters covering topics in reptilian incubation. The chapters
are written by several authors. This book is aimed at serving as a valuable reference text for …

SYNOPSIS. Egg size and nest site selection are two potential effects that can have a
persistent influence on the phenotype of offspring. In this paper, I develop the maternal …

Sex determination is the product of coordinated gene expression. Mutational analyses have
yielded great progress in our understanding of mammalian sex determination, and insight …

Channel catfish have an XX female‐XY male sex determination system. Although genetic
males of this species are readily feminized with exogenous steroid, the pattern of gonadal …

In many species of reptiles, sex is determined at fertilization by zygotic sex chromosome
composition. In other species, including all crocodilians, most turtles and some lizards, sex is …