How do marine creatures like crabs and lobsters regenerate their claws and legs?

Marine creatures such as crabs and lobsters have the ability to regenerate their claws and legs through a process called autotomy. Autotomy is the voluntary shedding of a body part, such as a limb, to escape from a predator or a dangerous situation.

After shedding a limb, a complex biological process takes place in the creature's body to regenerate the lost body part. The process involves the formation of a blastema, which is a mass of undifferentiated cells that can differentiate into various cell types needed for regeneration. The blastema grows and differentiates into the appropriate tissue types, such as muscles, nerves, and exoskeleton, to replace the lost limb.

Interestingly, researchers have found that some species of crabs and lobsters can regenerate limbs multiple times in their lifetime, while others can only do it once. The exact mechanism behind this difference is not fully understood and is still an active area of research.