why did they evolve to split aggressiveness/parentalness this way, rather than by sex?pic.twitter.com/v2ceXKHMYy
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Just read up about it. It is very, *very* unusual! (though, imho, the term 4 sexes is slightly misleading, but I understand why they chose it). The evolution of sex is still rather poorly understood, so I understand the excitement about this find
* 4 sexes is misleading, since there are still 2 genders: male and female. It is just that having m&f makes it so that a potential mate is 50% of the population. Then 50% out of that, to account for the dissociative mating (white/tan) so it becomes 25% potential mates
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