Ever been so scared you thought you were going to throw up? Well, that would be something you have in common with a sea cucumber! When a sea cucumber is scared or stressed it literally throws its guts up! This process is known as evisceration and is used as a defense mechanism. When threatened by a predator, the sea cucumber will expel its intestines in an attempt to distract the predators. The predators turn their attention to the internal organs and feast on them while the sea cucumber escapes!
|Sea Cucumber Anatomy:
What is often seen as a result of evisceration is the expulsion of many of the organs depicted in this picture above including the gonads, respiratory tree, circulatory system and intestines.
Thereare two forms of evisceration: In the first the cloaca ruptures and the internal organs are expelled. In the second form the entire anterior end of the sea cucumber’s body ruptures and the organs are expelled. But how can an animal rupture its own tissue on a whim? The answer lies in the sea cucumber’s unique connective tissue. Sea cucumbers have a huge amount of this connective tissue in the dermal part of their body wall. Within this tissue is a collagen compound that can transform from one state to another. Collagen is a fibrous protein, and in sea cucumbers the fibers are discontinuous which allows them to slide past one another. Controlled by the organism’s nervous system, in one state the collaged is stiff and non-elastic which provides strong support. In the opposite state, the collagen is soft and fluid like allowing the sea cucumber to be flexible and squeeze through tiny cracks.
What do you do with half a sea cucumber?
If a sea cucumber ruptures half its body in a last ditch effect to survive how can it survive with only half its body? Well, luckily sea cucumbers belong to the phylum Echinodermata which have remarkable powers of regeneration. Studies have shown that nerve and organ regeneration completes in 3-5 weeks after evisceration. Sea cucumbers can be thought of the oddest superhero with the strangest super powers: the ability to lose part of its body and grow it right back!
Video graphic Evidence!