Children develop a rudimentary gender identity by age three, having learned to classify themselves and others as either males or females.
It is therefore difficult to classify such users as either males or females.
Individuals of this species mature initially as either males or females.
But male mice with no copies of TRP2 tried to mate with either males or females.
The metabolite 8-OH-NVP was not detected in the intraluminal media from either males or females.
Relative growth in the service sector, by contrast, bears little relationship to relative wage changes for either males or females.
There were no group differences in risk factors for males or in protective behavioral strategies for either males or females.
One of the most enduring and controversial questions in the neuroscience of sexual behaviour surrounds the mechanisms which produce sexual attraction to either males or females.
The best fossils are once again those of the Rhynie cherts, which preserve the internal anatomy, including specimens that have the reproductive organs of either males or females (Dunlop et al. 2003).
Vasey thinks that this would have provided an evolutionary benefit, and that females--who masturbate when they mount either males or females--discovered they could get similar sexual gratification out of mounting females.
This is different from South American squirrel monkey species, where either males disperse from their natal group or both sexes disperse.
