Male pregnancy is restricted to seahorses, pipefishes and their relatives, in which young are nurtured in the male's brood pouch. It is now clear that the brood pouch has a further function. Studies of Gulf pipefish show that males can selectively abort embryos from females perceived as less attractive, saving resources for more hopeful prospects later. This is the only known example of post-copulatory sexual conflict in a sex-reversed species.
- Kimberly A. Paczolt
- Adam G. Jones
