Determination of sex from the femur measurements has been attempted in several populations and various studies have demonstrated the importance of population specific standards in the metric assessment of sex. The present study attempts to establish metric standards for sex determination by using femur measurements for ancient Japanese populations. Osteometric data were obtained from 151 adult ...

The transcription factors SF-1 and WT1 play pivotal roles in mammalian gonadal development and sexual differentiation. In human embryos, both SF-1 and WT1 are expressed when the indifferent gonadal ridge first forms at 32 days post-ovulation. As the sex cords develop - providing morphological evidence of testis differentiation - SF-1 localises predominantly to developing Sertoli cells in the se...

Electrocommunication signals of electric fish vary across species, sexes and individuals. The diversity of these signals and the relative simplicity of the neural circuits controlling them make them a model well-suited for studying the mechanisms, evolution and sexual differentiation of behavior. In most wave-type gymnotiform knifefishes, electric organ discharge (EOD) frequency and EOD modulat...

Brain development diverges in males and females in response to androgen production by the fetal testis. This sexual differentiation of the brain occurs during a sensitive window and induces enduring neuroanatomical and physiological changes that profoundly impact behavior. What we know about the contribution of sex chromosomes is still emerging, highlighting the need to integrate multiple facto...

A combination of analytical and simulation models is used to explore the initial evolution of genic sex determination from polygenic sex determination. Prior studies have indicated that polygenic sex determination is rare or absent in extant species but that it has likely played an important intermediate role in the evolution of other genetic sex-determination systems. This study explores why p...

Reptiles have a wide diversity of sex-determining mechanisms and types of sex chromosomes. Turtles exhibit temperature-dependent sex determination and genotypic sex determination, with male heterogametic (XX/XY) and female heterogametic (ZZ/ZW) sex chromosomes. Identification of sex chromosomes in many turtle species and their comparative genomic analysis are of great significance to understand...

Many aspects of social behavior are controlled by sex-specific pheromones. Gender-appropriate production of the sexually dimorphic transcription factors doublesex and fruitless controls sexual differentiation and sexual behavior. miR-124 mutant males exhibited increased male-male courtship and reduced reproductive success with females. Females showed a strong preference for wild-type males over...

In reptiles with temperature-dependent sex determination (TSD), the temperature at which the eggs are incubated determines the sex of the offspring. The molecular switch responsible for determining sex in these species has not yet been elucidated. We have examined the dynamics of yolk steroid hormones during embryonic development in the snapping turtle, Chelydra serpentina, and the alligator, A...

In contrast to our understanding of testicular differentiation, ovarian differentiation is less well understood in vertebrates. In mammals, R-spondin1 (Rspo1), an activator of Wnt/β-catenin signaling pathway, is located upstream of the female sex determination pathway. However, the functions of Rspo1 in ovarian differentiation remain unclear in non-mammalian species. In order to elucidate the d...