Lizards take the term fight-or-flight to a whole new level. When pulled by predators, lizards shed their tails in response. This self-amputation is called autotomy.
The severed tail continues to wiggle for about 30 minutes. It follows an elaborate repetitive and diverse motion. Which includes flips up to 3 cm in height. This distracts the predator enabling the lizard to escape.
Researchers at Aarhus University have found what allows lizards to shed their tails easily. They looked at the mechanism of tail autotomy in the nocturnal lizard Tokay gecko. It occurs at pre-formed horizontal fracture planes or areas of weakness.
The tail gets fractured or split within the vertebra at this area. Lizards aid the process by contracting muscles around the fracture planes. The pulling apart of the muscles causes the tail to fall off along the line of weakness.
Some species of lizards then regenerate the broken tails over six months to a year. Autotomy is also found among certain worms, salamanders, and spiders.