According to engineers at the Georgia Institute of Technology, fire ants act like a fabric or a thick liquid when swarming together.
Nobody has really bothered to study fire ants before, having been generally more interested in cursing at them and running quickly away from them, but a couple of mechanical engineers at the Georgia Institute of Technology noticed some pretty incredible properties upon examination. Turns out fire ants, when in groups, grasp onto each other using their mandibles, forming an intricate and precise pattern something like a Gore-Tex fabric.
This fabric-like bunching is even weirder than it sounds: The group of ants can be molded almost like a thick liquid (Wired compares it to honey or ketchup), and it will retain that shape even when manipulated. To undergo a waterproofing test, the engineers simply spun a bunch of ants in a cylinder, forming them into a near-perfect sphere in the same way you might form a meatball, if you used scientific equipment and not your hands while cooking. These ant-balls, with about 500-8,000 stinging bugs per ball, were dropped into a vat of water, where they assuredly did not drown.