The Itsy-Bitsy Spider

Has very big eyes and is a lot smarter than you think

Comments (0) By Margaret Wertheim Wednesday, Mar 1 2006

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Spider researchers still use lures, but there is only so much cobbling you can do under a microscope. (The making of the lures is so “fiddly,” Pollard says, that he depends on a man in Kenya just for the purpose.) These days scientists supplement actual lures with virtual ones, using movie-industry animation software to concoct mutant horrors for their arachnid audience. Their silver screen is about the size of a 35 mm frame, and it’s generally placed at the top of a ramp. “Jumping spiders like to climb things,” Pollard notes, “so if you give them a ramp, they’ll run up it. And if they encounter what they think is prey, they will begin stalking.”

The reason to study jumping-spider vision, Pollard adds, is not merely to understand what the spider sees, but to try to get a handle on how the spider’s mind works. The goal, he says, is “to know the mind of a spider.” Harland has recently been awarded a large research grant to develop computer models of the vision systems of a particularly cunning spider known as Portia. Roboticists are especially interested in the work, which may shed light on how to build better robots. “Something with a brain this small shouldn’t be able to do these kinds of things,” Harland says. Portia’s ability to strategize an attack, to work out complex paths to reach a target, or even to engage in tactics of deception go well beyond our usual view of an insect’s capabilities. “Our normal understanding of brains doesn’t allow this kind of behavior,” says Harland. “So how do they do it?”

Spider TV: Portia attacks virtual prey. Courtesy Dr. Duane Harland

Bug-eyed: Jumping spiders feature a big lens plus a smaller one at the rear � the same principle as the Galilean From Complex Worlds, Ed. Frederick R. Prete

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Harland is now beginning to model Portia’s vision with virtual robots; he will program these agents to see as the spider does and fine-tune the software as he learns more. The traditional view of spiders, Pollard writes in a forthcoming book, is that, “being so small and primitive,” they must be automatons. In view of recent research, that conclusion has to be re-evaluated. “It is clear to us,” he continues, “that when we look into Portia’s dark, bulging eyes, the lights are on, somebody’s at home, and a lot more than an eight-legged automaton is staring back.”?