Photographer Lev Fedoseyev captured stunning video of a herd of stampeding reindeer in the Arctic Circle moving in an enormous swirling pattern. When reindeer are threatened they form a massive deer 'cyclone' to protect each individual animal from being targeted. The reindeer ring keeps fawns and does near the center while bucks form a protective wall around them. Similar behavior has been witnessed in other mammals, including elephants, bison, and dolphins.