Haig, David2016-08-232014Haig, David. 2014. “Sexual Selection: Placentation, Superfetation, and Coercive Copulation.” Current Biology 24 (17) (September): R805–R808. doi:10.1016/j.cub.2014.07.039.0960-9822http://nrs.harvard.edu/urn-3:HUL.InstRepos:27867248The evolution of placentas in poeciliid fishes is associated with conception of overlapping litters and male mating strategies becoming more coercive. Sperm competition in ovaries of multiply-inseminated females may favor fertilization of immature eggs during ongoing pregnancies.en-USJournal Article2015-10-08David Haig2016-08-2310.1016/j.cub.2014.07.039