It occurs to me that unless someone else posts before I finish writing this, I'll have two posts in a row. I don't mean to spam, honest I don't guv'nor. But since my previous post was made 16 hours ago and there hasn't been another since, I suppose I can get away with it.

Where was I? Right. Sea cucumbers.

The sea cucumber is a name that encompasses roughly 1150 species of animal that can be found on sea floors throughout the world. On deep ocean floors they are by far the most numerous animal, and can also be found in extremely shallow waters only a few feet deep. Wherever you go in the ocean, there's a decent chance you'll find a sea cucumber nearby. The harder part will be knowing what you're looking at.

Sea cucumbers come in all sorts of colours and shapes and sizes, but most of them look like debris, poop, or psychadelic poop. They are simple creatures with no true brain, only a ring of neurons, but even if this ring is cut out of them they can still function just fine. They can be less than an inch to several feet long, depending on the species. They have a mouth, often filled with tiny tentacles to catch food like plankton and organic detritus, and they have a cloaca on the other end, which ejects all of its waste. Some species don't even have a stomach in between.

They don't have lungs, and they don't have gills. A sea cucumber breathes through what are called cuvierian tubules, which are thin, sticky strands that exist inside its cloacal opening. That's right. The sea cucumber breathes by sucking water into its butt.

When threatened, several species of sea cucumber will defend itself by shooting a number of these tubules out of its ass and entangling its predator in them. They are unpleasant and sticky, and often a distasteful chemical is ejected into the water at the same time. Some small animals, crabs and fishes, live inside a sea cucumber's butt to take advantage of the protection offered by these tubules. It takes the sea cucumber several weeks to grow new ones after ejecting them.

The act of ejecting its poo-lungs is known as evisceration.

They can move around on the ocean floor, and are capable of adjusting their bouyancy to float elegantly through the water like a slow motion fish. In some places they congregate in enormous numbers. One area of rocky shore on the southern coast of New Zealand contains up to 1000 Strawberry Sea Cucumbers per square metre, and is thus known as the Strawberry Fields.

But wait, they get even weirder. The sea cucumber is capable of tightening or loosening its entire structure. It can essentially liquify its own body and slip through small cracks and crevices to escape danger. Once safely tucked into any sort of cramped, twisted space, it can tighten its structure back up again and sit there, now solid in a completely different shape than normal, and wait until it feels like liquifying up again and slipping back outside.

The sea cucumber is used as food and medicine in China, where they raise sea cucumbers in farms of water that can be up to 1000 acres large. Sea cucumbers are fished up from the waters of Alaska as well, and these larger, more nutritional Alaskan versions compete with the homegrown critters in the Chinese market.

In one final weird note, the Japanese have written thousands upon thousands of haikus to sea cucumbers over the years. Their name for the sea cucumber translates as "sea mice", and they have also been known as sea slugs, even though that name is now more commonly reserved for a different, specific sort of animal. There has even been a book published of a thousand such haikus translated into English, called Rise, Ye Sea Slugs! If that's not awesome, nothing is.

Bonus picture: sea cucumbers are our friends! http://www.thenakedscientists.com/HTML/uploads/RTEmagicC_Sea_Cucumber_small.jpg.jpg