Module 10
Pipefish, along with seahorses, are both species in which the female deposits her eggs into the male, who carries and incubates them during gestation. In this case, the males must invest much more time and energy into their task of carrying the eggs than the female does. In a system such as this, with the "normal" sex roles reversed, sexual selection is also reversed. Therefore, we still see sexual dimorphism between the male and female, but it is the female who displays more of the related secondary sex traits, is visually more flamboyant, and participates in the courting of the male.
However, despite the divergence from what we normally observe, this mating system still proves the sexual selection hypothesis. The sex of the species who invests the most in the offspring is usually the one who chooses their mate, while the sex of the species who invests least in the offspring is the one who normally does the courting.
https://onlinelibrary.wiley.com/doi/10.1002/ece3.4459
https://www.sciencedaily.com/releases/2017/01/170104103555.htm
Caroline, great blog post! Both of our module 10 blog posts had similar ideas. However, a quote from your blog post that stood out to me was the very last sentence: "However, despite the divergence from what we normally observe, this mating system still proves the sexual selection hypothesis. The sex of the species who invests the most in the offspring is usually the one who chooses their mate, while the sex of the species who invests least in the offspring is the one who normally does the courting." I had never really thought of courtship and mating that way before. Overall, great blog post!
ReplyDeleteI agree with your comment that these species do still follow the sexual selection hypothesis--we just had to realize as humans that it's not about sex, it's about who invests more into the offspring! I enjoyed your post and the visual aid to see the difference in a pregnant male pipefish and the normal size of one.
ReplyDeleteCaroline,
ReplyDeleteIsn't it crazy how the male carries the babies in some species!! I wish it were the same for humans! I like how you talk about how males have to invest more time into the raising the young which is why they would be more selective for their offspring. Great work!