There's only two sexes. It's literally in our DNA and our chromosomes.

They're equally identified themselves as a third gender.

There are only three sexes.

I was one in the wrong body.

We're also seeing the consequences of what happens when we deny basic biological truths.

We're seeing men competing in women's sports.

That has, you know, very serious consequences for fellow competitors.

I'll lead up from police.

Maine knows that he's biologically male, but has decided to suppress that and continue punching women in the ring at the highest level.

Hello, I'm Fraser Myers-Tepsy, editor of Spikes. I'm absolutely thrilled to be joined by Colin Wright,

evolutionary biologist and editor

of the reality's last stand. Substac, welcome. Thanks for having me here. Colin, we live in a world,

incredible as it sounds. I'm going to ask you to explain whether biological sex is on a spectrum

or whether it's binary and whether humans can change sex,

because it seems an oddly contentious topic at the moment.

Yeah, yeah. It's really contentious and it shouldn't be. I mean, we've all known since we've

existed as a species that there's only two sexes. It's literally in our DNA and our chromosomes.

I mean, fundamentally, when we talk about the sex of an individual, it has, it boils down to

like the type of sex cell or gamete, sperm, or ova that you have the function to produce.

So just based on that alone, there's only two types of gametes that a person could make.

There's only sperm or ova.

There's no third, so there can't be a third sex.

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