The Paradox of the Lizard Tail, Solved
The New York Times
It can break off in an instant but also stay firmly attached. Scientists have figured out the microscopic structures that make this survival skill possible.
When choosing between life and limb, many animals willingly sacrifice the limb. The ability to drop appendages is known as autotomy, or self-amputation. When backed into a corner, spiders let go of legs, crabs drop claws and some small rodents shed clumps of skin. Some sea slugs will even decapitate themselves to rid themselves of their parasite-infested bodies.
But lizards may be the best-known users of autotomy. To evade predators, many lizards ditch their still-wiggling tails. This behavior confounds the predator, buying the rest of the lizard time to scurry away. While there are drawbacks to losing a tail — they come in handy for maneuvering, impressing mates and storing fat — it beats being eaten. Many lizards are even capable of regenerating lost tails.
Scientists have studied this anti-predator behavior meticulously, but the structures that make it work remain puzzling. If a lizard can shed its tail in an instant, what keeps it attached in non-life-threatening situations?