What is the term for a lizard's ability to shed its tail?

A lizard’s ability to shed its tail is called autotomy, more specifically caudal autotomy. It is a defensive adaptation that can let a lizard escape after a predator grabs its tail.

Many lizards have weakened areas in the tail that allow it to break at a controlled location. Muscles can constrict blood vessels, and surrounding tissues help close the wound. In some species, the detached tail continues to wriggle, distracting the predator while the lizard runs away.

Tail loss is not cost-free. A tail can store fat, assist with balance and locomotion, and play a role in social or mating behavior. Regrowth may take weeks or months, and the replacement is often shorter and supported by cartilage rather than a complete series of original vertebrae.

Autotomy should not be confused with molting, which is the shedding of skin, or regeneration, which describes regrowing lost tissue. Decapitation is unrelated and is not a normal escape mechanism. Not every lizard can shed its tail, and some species lose it only when the tail is firmly grasped.