Hmm . Life tends to do some weird things . I don ' t think you ' re being fair to umasteroforion . How about An environment where it is important to be able to sense magnetic fields for example , a desert full of big magnetic rocks that can be used as landmarks , and it has become ubiquitous among the species in the area . Then , just like we can communicate via sight , sound , and touch , and some creatures even communicate via smell , I bet that communication via magnetic field would arise . And THEN , just like how animals ended up using voice for more than communication within a species i . e . growls , roars and so on , this magnetic communication might become multiuse , too . And . perhaps after a while , there might be an evolutionary arms race based on the magnetic organ sexual selection prefers animals with a very powerful organ or something until we reach a point where there ' s an animal that can move magnetic dust or something , to camouflage . or something . As for how it would actually work , well , dunno , but electric eels can do electromagnetic things , so , shrug .