Current theories explain simultaneous hermaphroditism gives advantage those organisms that are widely scattered and slow, resulting in low reproductive frequency of contacts. It is hard to see why hermaphroditism is more widespread unless there is the downside as the counterweight.
It suggests that hermaphrodites suffer an energetic cost, as maintaining two sets of play and the cost due to reduction in number or viability of offspring that may result from accidents of self-fertilization. Behavior is consistent with model Tit-for-Tat cooperation. egg trade has three features rare, but potentially important. First, it almost certainly originated through interactions among unrelated individuals, unlike other ...