And I couldn't resist this one, for those that know me I'm sure you'll get a good chuckle (or a groan):
Well Endowed Fish Get the GirlsData in hand, Langerhans exposed about 50 females, one at a time, to video images of a male of average proportions at one end of an aquarium and an outsized male at the other end.
"They chose the larger one over and over," Langerhans said. "All females had the same preference."
Mosquitofish bear their young live, bypassing the whole egg-in-the-gravel hassle. Among such livebearing fish species, gonopodia range from less than 20 percent of a fish's body length to more than 70 percent. Don't ponder that too long, but trust that it fits into an evolutionary puzzle that spawned this study.