Red, White and Blue Crabs: These Tree-Climbing, Bird-Killing Crabs Come in Multiple Colors and No One Knows Why

Scientists are trying to solve the mystery of these big crabs' colorful differences. Photo Credit: John Tann Coconut crabs (Birgus latro) are gigantic land-dwelling crabs found on islands throughout the Indo-Pacific. They can live for decades, and can grow to be more than 3 feet wide (legs outstretched) and weigh in at more than 6 pounds. So that name isn't because they're the size of a coconut—it's because they can actually tear open coconuts to eat their tender meat. "If a coconut falls out of a tree, they'll clamp onto it on the top and then drag it back to their husking ground," explained Victoria Morgan, a PhD Candidate in the Department of Evolution and Ecology at University of California, Davis. You can always tell where a crab hides out by the piles of coconut husks lying around. And it just so happens that out these massive, tree-climbing crabs come ...