Starfish: the incredible secret of their self-amputation

Starfish can shed their arms to survive. How do they manage this feat?

Scientists from Queen Mary University of London have identified a neurohormone that triggers this phenomenon. This discovery could pave the way for new approaches in regenerative medicine.


When a predator approaches, some animals resort to a radical method: abandoning a part of their body. In starfish, this process is known as autotomy, a strategy that remains largely misunderstood.

By analyzing the common starfish Asterias rubens, researchers discovered that a neurohormone, closely related to the human hormone cholecystokinin (CCK), plays a crucial role. Released in response to stress, this hormone triggers a muscular contraction at the base of the arm, causing it to detach.

This seemingly extreme mechanism proves to be a significant evolutionary advantage. The starfish escapes from its predator by shedding an arm, which it can then regenerate thanks to its cellular regeneration abilities. The research, published in Current Biology, suggests that other factors are at play. Dr. Ana Tinoco, co-author of the study, indicates that other neurohormones might also be involved in this complex process.

The implications extend beyond the simple biological phenomenon. Understanding how some species regenerate their limbs can provide valuable insights for regenerative medicine, aimed at improving the treatment of human injuries.

According to Professor Maurice Elphick, this discovery "opens the door to exploring the regenerative potential of other animals, including humans." By unraveling the secrets of voluntary amputation in starfish, significant advancements could emerge.