In the interest of studying another species (other than newts) that mates multiply, stores sperm, and has a longer breeding season I began studying livebearing fish (Poeciliidae). I began by examining male and female mate preference in sailfin mollies, Poecilia latipinna. I have subsequently moved on to more evolutionarily based questions for my postdoctoral research. For my NSF postdoctoral research with Professor Mike Ryan, I examined the hypothesis of reproductive character displacement using a unisexual-bisexual complex of mollies (Poeciliidae). Amazon mollies, Poecilia formosa, are unisexual hybrids that arose from a mating between a male sailfin molly, P. latipinna, and a female Atlantic molly, P. mexicana. They reproduce by gynogenesis by eliciting sperm transfer from their parental species but inheritance is strictly maternal. Male sailfin mollies from the sympatric populations show a significantly greater strength of preference for conspecific females than do males from allopatric populations. Male sailfin mollies also produce more sperm in the presence of conspecifics vs Amazon mollies. Much more work has been done and is in progress - see my CV. Male P. mexicana, P. formosa, female P. latipinna , male P. latipinna