Theory of the Evolution of Sexes Tested with Algae (image) University of Adelaide Share Print E-Mail Caption Volvocine alga enabled a test of the theory of evolution of the sexes because of their varied differences in gamete size. This one is Gonium pectorale which has same-sized gametes. Credit Image credit: Environmental Protection Agency Usage Restrictions For use with this story only Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.