Carole Hooven, Ph.D.

very difficult to tell apart.

The females are very difficult to tell apart from the males.

They have this clitoris that looks exactly like a penis and experts often can't even tell the difference.

They're highly aggressive.

And that seems not to be mediated in the adult, at least by comparable levels of testosterone.

There seems to be potentially something going on in early development.

But I don't know of good evidence that testosterone acts similarly in females to mediate, say, aggression.

We'll say mating aggression.

No.

The males would be higher.

The males would be higher.

I believe they're either just as aggressive, if not more so.

I believe that they're dominant to the males.

Got it.

And there's something going on with potentially maternal adrenal androgens when the fetus is developing that becomes the aggressive female, but I don't think it's completely worked out.

I haven't looked at the literature on that in ages.

So phenotypic, we'll just stick to the body and then we can also talk about the behavior.

And I just want to say right at the outset that we have a sex determination system that relies on chromosomes, but not every animal does.

So chromosomes do not equal sex.

And birds have used chromosomes, but they have a different system where the female is the one that has heterozygotic chromosomes.