Male Sex Ornaments Are Fishing Lures, Literally

ScienceDaily (July 12, 2012) — Talk about a bait-and-switch. Male representatives of the tropical fish known as swordtail characins have flag-like sex ornaments that catch mates just like the bait on a fishing rod would. What's more, a study reported online on July 12 in Current Biology, a Cell Press publication, shows just what any good fly-fisherman would know: Lures work best if they mimic the foods that fish most often eat. For some characins in the study, that means males are waving pretend ants around in hopes of getting a bite.

"This is a natural example of a fishing lure designed to maximize the chance to catch a fish," said Niclas Kolm of Uppsala University. "In this case, it is not just any fish, however -- it is a fish of the opposite sex that the lure is designed to catch."

The findings also lend support to the notion that sensory drive can encourage fish and other animals to diversify and ultimately to become separate species. Sensory drive is the idea that communication signals will work best when they are a good match for their surroundings and that they will diversify when those surroundings vary.

Continued:   http://www.sciencedaily.com/releases/2012/07/120712131709.htm