The only general definition of "male" vs "female" in biology is smaller gametes vs larger ones (anisogamy)
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Replying to @arthur_affect
We call smaller gametes "sperm" and larger ones "ova" and picture motile sperm competing to fertilize sessile ova but that's not universal
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Replying to @arthur_affect
Plenty of examples where both types of gametes are motile and seek each other out, or both are non-motile and combined by other methods
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Replying to @arthur_affect
And that in turn predicts v little about the macro organisms that make smaller gametes vs bigger ones ("males" and "females")
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Replying to @arthur_affect
There is no rule in the animal kingdom that males are bigger than females, that they have genitals that we'd think of as "male", etc
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Replying to @arthur_affect
We all know that the "male" seahorse provides the smaller gametes but then gestated the fertilized eggs inside itself
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Replying to @arthur_affect
Or that male emperor penguins hatch broods of eggs while the females that laid the eggs roam to forage for food
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Replying to @arthur_affect
FEMALE HYENAS GIVE BIRTH THROUGH 7-INCH LONG CLITORISES
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Replying to @laureneoneal
I mean female hyenas have what looks to us like "male" genitals -- they give birth through a penis (officially "pseudo-penis")
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Replying to @arthur_affect @laureneoneal
It makes giving birth more difficult for them than other mammals but gives them far more control over mating
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Which is probably why it survived as a trait, it increases average fitness of offspring
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