To cut a long tail short: a review of lizard caudal autotomy studies carried out over the last 20 years

Reviews twenty years of work on lizard tail loss, covering when tails are shed, what shedding costs in locomotion, energy storage, growth, reproduction and social status, and how regeneration differs from the original.

Studied in

Squamata

Sample size

review of two decades of autotomy studies

Tail loss carries measurable costs: reduced sprint and climbing performance, loss of stored fat, slower growth, reduced reproductive output and lowered social status in several species. Regenerated tails are cartilaginous rather than vertebrate-boned, and are typically shorter and functionally inferior. Shedding thresholds vary with the value of the tail and with how threatening the encounter is.

• A review across many species using different measures, so costs are not directly comparable between studies.
• Most cost measurements come from captive animals, where the ecological consequence of reduced performance cannot be observed.

• Autotomy

  Shedding a body part works — the animal escapes. What follows is worse locomotion, lost energy stores, slower growth, reduced breeding and, in several species, a drop in social standing.

• Autotomy

  A lizard does not drop its tail whenever it is frightened. The threshold rises and falls with how dangerous the situation is and what the tail is currently worth — and what regrows is a cartilage rod, not a tail.