Sex Change Mystery Probed

[Shana A]

Sex Change Mystery Probed

by Abram Katz | March 19, 2009 3:40 PM

http://www.newhavenindependent.org/archives/2009/03/almost_all_orga.php

A strange group of molluscs, crustaceans, worms and fish have found a way to switch sexes to meet their mating needs. Why don't more of us follow suit?

A pair of Yale scientists used mathematical models to tackle that question — and reached a surprising conclusion that challenges conventional wisdom on the topic.

Many bluehead wrasse, for example, are born female. Some of the largest of the fish eventually turn into males and maintain a "harem," ensuring mating success.

That may sound bizarre, but Yale evolutionary biologists have studied organisms that can change sex (technically called "sequential hermaphroditism") and this month published their puzzling results. Their paper is in the March issue of The American Naturalist. (Read it here.)