Here's an overview of the main sex determination systems found in nature, which I've covered in recent posts.

This covers *determination*, but not the *definition* of the sexes. So what do all males and females have in common?
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There's a common notion that sex is always determined at conception, but that's not the case for turtles, crocodilians, and a variety of other reptiles and fish.
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feeling excited for spring and felt inspired to draw some plants (and bugs of course)

#bugsky

Fungus sex is super weird. Fungi can reproduce asexually or sexually, but there are NO male or female sexes in this kingdom. Instead, fungi evolved a wide variety of reproductive strategies. Broadly, species can be categorized as homothallic or heterothallic.
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Plant sex is weird. Like animals, plants evolved two types of sex cells: small, mobile sperm and large, immobile ova. Unlike animals, most plants don't produce just one or the other - they produce both!
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Not all animals and plants determine sex the same way. In birds, the familiar XY system is reversed. Having two of the same sex chromosome (ZZ) makes you male, while having two different sex chromosomes (ZW) makes you female.

You've heard of the birds and the bees, but did you know neither have X or Y chromosomes?

In bees, sex is weird. A fertilized egg becomes a female, so females have the normal 2 sets of chromosomes (diploid).

Unfertilized eggs become male (drones) and have only one set of chromosomes (haploid).

I think that the tweet genre of “this person (who might be a bot) had a bizarre opinion that made me think less of humanity and so the right thing by to do is screenshot it and show it to the largest number of people” is silly.

Hello Bluesky. Hoping to find a wholesome and engaging community here. Nice to have a clean slate, let's see what happens.