Size Matters: Narwhals With Longer Tusks Have Bigger Testicles

Narwhals grow long tusks, if they have the balls to do it. The spear at the end of the male sea unicorn has been variously thought to be a sensory organ, a device for battling other males, or an elaborate reproductive signal. New evidence shows they're the whale version of peacock feathers. » 9/22/14 8:04pm Yesterday 8:04pm

These fish lure unsuspecting mates with genitals camouflaged by fake…

Evolution seems to know no bounds when it comes to shaping organisms in a way that's meant to help them survive and reproduce — a process that often leads to some pretty bizarre characteristics and behaviors. And now, thanks to the work of biologists Niclas Kolm and Göran Arnqvist, we can add another example to the… » 7/12/12 3:40pm 7/12/12 3:40pm