Jumpin' Gecko Tails!

"Severed Lizard Tail Has a Mind of Its Own"
LiveScience (September 9, 2009)

"It's amazing enough that lizards can shed their tails as a decoy for predators and entertainment for young boys. But a new study of geckos documents an incredible set of acrobatics that these severed tails perform.

"Though it might seem as though a lizard loses its tail because it's pulled off, in fact the lizards control the severing, apparently when they sense they're about to become dinner.

"The tails exhibit not only rhythmic but also complex movements, including flips, jumps and lunges, after the tails are shed, Anthony Russell of the University of Calgary and Tim Higham of Clemson University report in the journal Biology Letters...."

The tail may have a brain of its own, although that's not quite the same as a "mind." Clever headline, though.

It looks like a bit of the spinal cord, at the other end from where the tail was attached, controls the separated tail's complicated motions. When the tail is on the lizard, presumably the signals are overridden by instructions coming from the brain.

I didn't know this: Gecko tails don't get pulled off. According to this article, the lizard controls the separation. How, it doesn't say.

Aside from finding out more about gecko tails, the studies outlined in this article may help scientists learn more about how spinal cords in general - including ours - work, and what happens when they're injured.