Even in harem species, on average, each male gets exactly the same number of offspring as a female. If say 75% of the specimen would be female, being a male wou

Even in harem species, on average, each male gets exactly the same number of offspring as a female. If say 75% of the specimen would be female, being a male would yield on average thrice as much children compared to a female, so it would be evolutionary beneficial to be male. The only species where the ratio is different are those where sex is determined with different genetic mechanisms. For example, in hymenoptera (ants and wasps), males are born from unfertilized eggs, which results in a 1:3 ratio between females and males.