Can Orb Weaver Spiders Solve Novel Problems?

The ability to solve problems varies greatly between animal species. Some animals are thought to use insight. Insight is the ability to solve a problem in one attempt after an impasse, which differs from trial-and-error learning or pre-programmed responses in that animals “think” of a solution to a problem before attempting the solution. We analyzed the novel problem-solving abilities, and whether these abilities include insight of two species of orb weaver spiders, Larinioides sclopetarius and Araneus diadematus (Araneidae). These spiders are sit-and-wait predators that might not be expected to possess such abilities given their biology. We first tested the problem-solving hypothesis, which states that these spiders can solve a novel prey capture problem. We then tested the insight hypothesis. Finally, we tested the species differences hypothesis which states that spider species will differ in their likelihood and method of solving the problem. To test these three hypotheses, we subjected wild spiders to the problem of receiving prey directly in their mouthparts as opposed to in their web. In order to solve the novel problem, the spider was required to wrap their prey and secure it to the web. We recorded whether each spider was successful at solving the problem, the behavior used when successful, and whether the spider solved the problem in one attempt. Most spiders of both species solved the problem. Different spiders used different behaviors to solve the problem, but those behaviors occurred with similar frequencies in the two species. Our results provide evidence that these spiders solve problems and have the ability to use insight