Dancing to the beat makes fiddler crab sexual… failures.

New Scientist turns our human expectations upside down once in the world of fiddler crabs. They seem musical (thus the name, after all), and they use that rhythm to win mates. But on closer inspection, the better they dance, the less of a catch they are for the opposite sex:

In the cut-throat world of sex, where animals try to get noticed rather than blend in, this synchronised mating dance is unique. So why do the crabs do it?

One theory is that this coordination may be a special brand of crustacean camaraderie, with groups banding together for the greater good.

But this romantic ideal just doesn’t have legs, according to Australian National University researchers led by Andrew Kahn, who found that mavericks dancing to their own tune get twice as much attention from females as their conformist neighbours.

This means that crabs are probably not waving together on purpose, because animals are unlikely to evolve traits that make them sexually unattractive.

Fiddlers, Kahn’s team says, are actually trying to outfox each other like any other selfish animal – they just aren’t very good at it.

Crab-style dancers, there’s hope for us yet….