How can sea cucumbers expel and regrow internal organs?

Many species of sea cucumbers possess the remarkable ability to expel their internal organs through the anus, a process known as autoevisceration. This action may serve as a defense mechanism to escape from predators, or it may occur due to unfavorable environmental conditions or on a seasonal basis. Some species also discharge specialized sticky filaments to further confuse or ensnare potential threats.12

Following this expulsion, sea cucumbers are capable of regenerating a new set of internal organs within several weeks. This process is a testament to the well-developed regeneration abilities found throughout the phylum Echinodermata, which allow these animals to recover lost or destroyed body parts. While the exact triggers for this regrowth are complex, regeneration in animals is often stimulated by physiological needs, ensuring the recovery of essential bodily functions.23