Male water fleas observed for first time

University of Buffalo researchers say they have observed the first male water fleas scientists have ever seen.

The UB scientists say their discovery opens a new window on the biological diversity of several species of water fleas, including those in the genus Daphnia and the genus Bosmina, that play major roles in freshwater food webs.

Water fleas are nearly microscopic organisms with transparent bodies. Found in lakes, ponds and other bodies of fresh water, they are crustaceans, like lobsters, and not insects, as their name suggests.

In stable environments, female water fleas generally reproduce asexually, essentially cloning themselves and resulting in populations of females that are practically impossible to tell apart. Water flea populations grow much faster when they reproduce asexually than when they do so sexually, Derek Taylor, associate professor of biological sciences and co-author of the paper, explained.

He said the practice of rarely producing males has likely existed for 100 million years or more in a large group of freshwater crustaceans.

The study appeared in November's Proceedings of the Royal Society: Biological Sciences.

Copyright 2005 by United Press International