Here's a story about a fish. And this fish isn't staying where it's supposed to be. We'll get to that in a moment. First, the basics. The climbing perch is a fresh-water fish native to Papua New Guinea, olive green color and about 10 inches long. So not too big, but it's kind of a tough guy. Dr. Nathan Waltham, a researcher at James Cook University in Queensland, Australia, says its gills cover both sides of its head. "It can extend that out and it can lock those into place. And along the edge of those gill plates are sharp spines," he says. Waltham is an expert on the climbing perch and what its fierce-looking gills can do. "They can flex out those gill plates on the side of the head, which means they can actually — with the sharps spines — leverage themselves across land," Waltham says. "So if you can visualize a water hole that's drying up, conditions becoming unfavorable — and this fish can detect that and decide then to move out of that water. So by using those sharp spines [it ca
