12.8 Why is homosexuality an evolutionary “problem?”

Some biologists have referred to the evolutionary problem with homosexuality, because same-sex sexual behavior is non-reproductive, yet homosexuality occurs in relatively high numbers—enough to support an adaptive function for homosexuality. So the big question is: how can natural selection work on a trait that seems unable to increase an individual’s fitness?

  Points to Ponder

What do you think? How can a trait that is associated with non-reproductive sex be selected for? How could homosexual preferences increase an individual’s fitness? Answer in full sentences.


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The Evolution and Biology of Sex Copyright © 2020 by Sehoya Cotner and Deena Wassenberg is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License, except where otherwise noted.