Singing fish take their cues from melatonin.

Jumping spiders (Salticidae) are renowned dancers, but until recently, the music of their courtship was thought to fall on deaf ears. No one had heard of spiders being able to perceive sounds until a recent serendipitous finding published in Current Biology by Ronald Hoy and colleagues from Cornell University, USA. Having previously shown that the spiders rely heavily on vision as they strut their stuff, Hoy’s colleagues, Paul Shamble and Gil Menda, were intrigued when they noticed that the spiders also reacted to sounds made by a creaky lab chair: the noises triggered nerve signals in the spider’s brain. This led to subsequent experiments where clapping elicited more brain activity, and eventually the researchers designed a more detailed series of experiments designed to test the spiders’ hearing more thoroughly.