Hawaiian stick spiders re-evolve the same three guises every time they island hop. We don't usually expect evolution to be predictable. But Hawaiian stick spiders of the Ariamnes genus have repeatedly evolved the same distinctive forms, known as ecomorphs, on different islands, researchers report. Ecomorphs -- which look similar and live in similar habitats, but aren't as closely related as they appear -- are surprisingly rare. The researchers hope that these newly described ones might help us understand this strange evolutionary pattern. Source 9iImage from Science Daily by George Roderick.