For most animals the natural world is a rough place. The danger of being eaten by predators is always present. Some animals can detach a tail or a limb along a point of weakness to escape the grasp of a predator. The phenomenon is called autotomy, and scorpions are a good example.
Though scorpions can ward off most predators with its venomous sting, its self-defense system isn’t fool-proof. So, it moves to plan B. In 2015, an international team of biologists reported discovering that when tropical scorpions are grasped by the tail, they break it off and escape.
The tail is an important part of a scorpion’s anatomy. It contains the sting that it uses to subdue prey and defend itself from predators. Even more importantly, it contains the anus, without which the scorpion can’t poop. How could it possibly live without it?
The researchers found that the tail scar quickly sealed itself up against fluid loss. Without a sting, scorpions couldn’t capture large prey, but they could still catch and devour small crickets well enough to live on for at least eight months. Scorpions don’t produce much bodily waste, but what they did produce accumulated in a swollen mass at the end of the animal’s tail stump. They sometimes rid themselves of this load by losing another tail segment.
The ability to lose their tail really benefits scorpions, because afterwards, they can still mate and pass on their genes. If they had been eaten by the predator, they couldn’t reproduce. That makes autotomy an evolutionarily adaptive trait.
Find Out More:
- “Scorpion Sheds ‘Tail’ To Escape: Consequences and Implications of Autotomy in Scorpions” (PLoS ONE video)
- “Tail Autotomy of a Japanese Grass Lizard” (YouTube)
- “Lizard Behavior and Life History—Tail Loss (Caudal Autotomy)” (CaliforniaHerps.com)
- “A Guide to the Amphibians and Reptiles of California Scorpion” (National Geographic)
- “Scorpions Break Off Their Tail (With Anus) To Escape Predators” (IFL Science)