By Susan Milius
A champion sex molecule has turned up in an analysis of sea lampreys, and it may inspire new ways to defend trout and other Great Lakes fish against the invading bloodsuckers.
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Long and skinny, the adolescent sea lamprey goes through a parasitic phase in which it clamps its toothy mouth onto another fish and feeds on the host’s blood for weeks. The sea lamprey is native to the Atlantic coast but wriggled westward in the past 200 years as shipping channels opened. Sea lampreys “have been the most devastating invasive species ever to move into the Great Lakes,” says Weiming Li of Michigan State University in East Lansing.