The Two-Way
3:51 pm
Thu January 5, 2012

Researchers Say Male Spiders 'Eavesdrop' To Steal Opponents' Dance Moves

A new discovery suggests that the behavior of spiders may be as complex as some vertebrates. In the study, published in this month's issue of the journal Biology Letters, scientists showed that male wolf spiders will eavesdrop on a male opponent to learn their mating dance moves and in some cases improve on them.

Wired explains how the scientists came to the conclusion:

"The researchers put male wolf spiders (Schizocosa ocreata) in front of tiny television sets and made them watch videos of other males perform a sexy, leg-tapping mating dance. The test spiders copied the on-screen males, adjusting the rate of leg-tapping to match and even outperform their rivals.

"The spiders used in this study were collected from the field. Naïve, lab-raised spiders who weren't exposed to male courtship toward females didn't understand the dance and the results were inconclusive. But spiders from the field, who knew what the leg-tapping was all about, behaved as if their on-screen rival was courting a nearby female."

Here's a video of the experiment:

And while this may all sound like silly high school prom games, the findings do tell us something. Here are a couple of points from the scientists that we took from the press release:

-- David Clark, a professor of biology at Alma College, said, "Eavesdropping on the communication of others is widespread among animals and often serves as a means of obtaining information. For example, studies of birds, mammals and fish have shown that male bystanders observing male-male contests can learn about the strengths of potential opponents, while female observers may copy the mate choices of others. This new discovery shows that male wolf spiders also eavesdrop on the visual signals of courting males."

-- George W. Uetz, a professor of biological sciences at the University of Cincinnati, adds, "This 'signal matching' behavior has only been seen before in vertebrate animals like birds or fish, and suggests that invertebrates like spiders may have more sophisticated behaviors than previously known. The closer we look at spiders, the more complex we see they are. Their capacity for learning, memory and decision-making is far greater than we ever would have thought."

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