It's partly biological but there are still many existing cultural attitudes that discourage husbands from performining traditionally "feminine" roles/tasks when caring for their kids.

The author's point about being over-critical of sexism is well-taken, but by reducing the sexist attitudes towards, for example, stay-at-home dads, it may be possible to help more women in STEM have fully productive careers.

> it's biological

"It's biology" has a long history of being used to justify everything from sexism to racism to genocide. Please provide a source for your claim (and for the implied claim that men do not have the same drive).

The source is looking at nature and all the species?

But that doesn't mean we, the smartest of them all, can't make some changes. Nature is also killing the weaker etc, things that we don't agree on as humans.

And of course you were downvoted, while the one claiming "biology!" based on no arguments wasn't.

It is sexist because you are dismissing women being treated as lesser beings with some armchair analysis.

I disagree with the poster you are replying to, but I also disagree with what seem to be the implications of you comment -- that someone who prefers performing childcare over STEM work is a "lesser being"?

No no, lesser being as in "we decide your duties and remobe your opportunities".