never tell terfs about white-throated sparrow or they will lose their fucking minds

Do you want to hear about white-throated sparrows?!

Of course you do, they’re fantastic. They come in two models, one with tan head stripes and one with white head stripes. But the gene that controls stripe color also has a bunch of other effects! It’s a supergene!

To briefly sum up a grueling amount of fieldwork by people who were probably not getting paid nearly enough, basically the tan-stripes are nurturers and the white-stripes are fighters, across both males and females. White-stripes chase away intruders more, tan-stripes bring more food to the nest. Tan-stripe females bring more bugs to their chicks than white-stripes, white-stripe females are more aggressive and sing more.

There is a reason Jordan Peterson picked lobsters, not sparrows, to get all MRA about, because the sparrow ladies are ALL about the tan-striped males. Sexy nurturing tan-stripe males are immediately grabbed up by the more aggressive white-stripe females (who are also dead sexy if you’re a sparrow.) Then the remaining birds pair off, so you get tan and white couples reproducing in virtually all cases—nurturing male with aggressive female, hyper-aggressive male with hyper-nurturing female.*

And this is good!** Because it turns out that they can have a tough time if they don’t mate across stripes—white x white sparrows often come out undersized if they come out at all. There was some cool recent genetic sequencing and one particular chromosome is way funky, inverted, and scrambled in the white-stripes. So now every white-stripe has a funky chromosome and a normal one, and every tan-stripe has two normal ones.***

This is all really unique and means that white-throated sparrows effectively have four sexes, because they now only reproduce with a member of the opposite stripe and sex chromosome, and their offspring may be any one of the four sexes. The stripes have essentially become a second sex chromosome.

The geneticists involved think the funky chromosome probably showed up as a weird import from somebody gettin’ jiggy with another sparrow species. Presumably this created a hypersexy female whose white head stripes brought all the boys to the yard, and very unusually, that bred true.

Is that cool or what?!

*No word on whether there is a resulting sparrow tradwife media genre.

**Leaving aside the impact on the emotional health of the non-sexy sparrows.

**A population solely of tan-stripes can reproduce safely, they’re just not that into each other.

I reblogged this a minute ago but I’m going to reblog it again, because I want to add another non-binary bird species: the ruff.

First of all, look at it.

That’s a male ruff, specifically. You can see how they get their name. The females don’t have that fancy collar. They just look like sandpipers, which is what they are.

Like other sandpipers, these are wading birds, but they live in wet meadows and marshes instead of by the seashore. During the breeding season they gather together and the males hold territories, called leks, in which they display to attract females.

At least, some of them do.

Some male ruffs do not display in leks. They have plainer, often white, neck ruffs, and they sort of wander around the display grounds courting the females wherever. The interesting thing is that the territorial males tolerate this. Research suggests it’s because females are more interested in a display ground that has both kinds of males. The ladies like variety, it seems.

But it gets even more complicated. In 2006, a third male form was discovered. This form is extremely rare, and doesn’t have male display plumage at all. It looks just like a female ruff in the field. The other birds, however, can tell the difference, judging by their behavior. These female mimics travel with other males when the sexes split for the winter, and during homosexual mountings (which are common, as they are in many other animals), they often top.

What’s really interesting about these ‘cryptic males’, or faeders, is that they are apparently super sexy. Seriously. Females and males both prefer mating with them. And it’s believed that, like the satellite males, the presence of a faeder attracts more females to the area, which benefits all three forms.

And the thing about these forms is they are fundamentally different from one another. The plumage and behavior differences last throughout a bird’s life, and are determined by genetics. They are functionally three different genders - one of which shows natural intersex characteristics. All three can breed with females, and females are more interested in breeding when all three are present. They know that diversity is the good shit. Which makes them much, much smarter than TERFs.