The sea cucumber is at the bottom of the oceanic food chain, quite literally. The cylinder shaped invertebrate, ranging in sizes up to a couple of meters, travels the bottom of the sea, from warm tropical climes, to the deep, cold clefts of the polar regions.

Far from being the pretty green vegetable we toss into our salads, but drawing their name from its shape, the sea cucumber possesses multiple modes of locomotion, the better to drift over the seabed and eat decaying vegetation and other material. 

Five double rows of tiny tube feet run the length of its body, their suction cups enabling them to travel along the rocks and sand. They can also use the 30 tentacles surrounding their mouth, which are modified tube feet, to drag themselves along in their scavenging for food.

Unattractive as they are, the sea cucumber does have enemies, including turtles, crustaceans, fish, and humans. They are said to be quite a tasty dish, if your appetite has not been ruined by their primary defense mechanism- ejecting all their internal organs, in an attempt to confuse and distract predators, so they can escape. The organs will re-grow, later.