Some males of new species have one limb bigger than the other
Unlike the guy with two left feet, males of a new species of dance fly from Japan’s Mt. Fuji often grow feet that don’t match at all.
Dance flies are named for their erratic flight moves in mating swarms. Males of the new dance fly species can grow asymmetric front legs, one an unsurprising slim fly leg and the other ornamented with what looks like a little tufted balloon, says Christophe Daugeron of the French national research agency CNRS and the National Museum of Natural History in Paris. He and his colleagues give the fly an official scientific name, Empis jasch