 A test in a deliberately artificial environment explored P. labiata ′ s ability to solve a novel problem by trial and error . A little island was set up in the middle of a miniature atoll , and the space between with them was filled with water . The gap was too wide for the spiders to jump all the way , and the spiders ' options were to leap and then swim or to swim only . The testers encouraged some specimens by using a small scoop to make waves toward the atoll when the spiders chose the option the testers preferred ( leap and then swim for some spiders , and swim only for others ) , and discouraged some specimens by making waves back toward the island when the spiders chose the option the testers did not want – in other words , the testers " rewarded " one group for " successful " behaviour and " penalised " the other group for " unwanted " behaviour . : 284 – 286 Specimens from Sagada almost always repeated the first option they tried , even when that was unsuccessful . When specimens from Los Baños were unsuccessful the first time , about three quarters switched to the other option , irrespective of whether the first attempt was by leaping and then swimming or by swimming only . : 287 – 288 
