Successful species have two main drives- survival and reproduction. In many species of the jumping spider, these two drives create a biological tug-of-war for males, because female jumping spiders can be cannibals. To survive that battle between fear and lust, male jumping spiders have developed signal adaptations to be attractive to females for mating and repellant for eating. In the Taylor Lab at the University of Florida, researchers go the extra mile to sort those signals out.
So what might those signals be? Well, they’re mixed: Habronattus pyrrithrix males have enchanting red faces, which happens to be a color that signals toxicity in prey. But an especially rosy complexion can also signal that a male is healthy. “If we give them a really good diet, their faces become brighter,” says Lisa Taylor, a behavioral ecologist who runs the lab. “That all suggests that females should be paying attention to color.”
To figure out whether they were noticing, the researchers presented female spiders with male suitors who were either bare-faced or painted over with black liquid eyeliner (Urban Decay, if you must know). The data is still trickling in, but Taylor is finding that female spiders are indeed less likely to attack males with red faces versus their face-painted peers.
This suggests a red face is a kind of double signal. Well-fed males are redder, which may be a sign of their fitness. But red also acts as a deterrent, tapping into a female’s aversion to a color that typically screams I’m toxic. “One is like, I have to tell you how good I am, and the other one is, OK, I’m going to do all these things so you don’t eat me,” says UC Berkeley behavioral ecologist Damian Elias, who also studies jumping spiders.
Other species do it differently, which means, for example, gluing false eyelashes onto spiders to make them look bigger from a distance. Read about the business of altering how spiders look at Wired. -via Digg
(Image credit: Taylor Lab/University of Florida)