Sexual selection is different than what is "needed" by a species. Males who are able to fight off others and therefore are the exclusive mates of a large group of females will propagate the genes that reinforce their physical prowess and aggressive behavior.
This also benefits the females if they will have sons who are more likely to win their own harems.
But there are also competing strategies. Sneaky males who can mate with another male's group without fighting him off will also propagate their genes. Females in the group benefit if they will have sneaky male offspring who will be similarly successful.
"Strong" is not the default for "most likely to have offspring." There are many strategies, including monogamous species which invest together in their offspring. Evolutionary psychology can get oversimplified and misapplied, especially by beta males whose mothers hurt their feelings and now lash out at women whenever they get the chance. That last bit was an attempt at irony, btw.
numberfour002@lemmy.world 2 months ago
Just thought I’d mention that there are species of fish and other animal groups that are all female or close enough to it that their populations do not rely on males to propagate. For example, Amazon mollies. I couldn’t tell you if any species of betta are capable of parthenogensis, but as a general statement “If you would have only females, the entire fish species dies out” isn’t universally true.
Although it’s possible that female bettas want strong males, I’m certainly not a female betta and don’t want to get too far into the territory of anthropomorhpism and there are certainly other possible motivations and processes going on than simply wanting “strong males”.
But really, all this seems to be veering oddly away from the original topic and my first comment, so I’m just going to leave it at that.
1984@lemmy.today 2 months ago
Of course. Never intended my comment to be a book on the subject. :)