Sea Pigs, One Of The Weirdest Animals In The Sea
When it comes to odd animals, the sea pig has got to be one of the weirdest in the world — or, at least, the weirdest located some thousands of feet under the ocean.
Sea pigs were first identified by Swedish zoologist Johan Hjalmar Théel during his global mid-19th-century expedition aboard the HMS Challenger. Despite its name, the sea pig is not related to land-dwelling swine. Instead, it got its funny name because of its pinkish hue and strangely shaped "limbs," which make it look as if it has two pairs of ears and walks on four legs like a land pig.
The sea pig is considered a type of sea cucumber or echinoderm, and this weird animal lives deep below the ocean's surface between 4,000 and 16,000 feet. It possesses a pair of "antennae" on its feet.
These tubular appendages are connected to a "water vascular system," which allows the sea pig to move about the ocean floor by sucking in and releasing water, essentially gliding through the water via hydraulic pressure. Sea pigs also possess tentacles near their mouths. These strange physical features enable the squiggly creature to scoop their food into their mouths and feed.
Besides its bizarre appearance, the sea pig's breathing system is also astonishing. These strange creatures rhythmically expand and contract their bodies to pump water into their anuses, which they then filter through a lung-like structure called the respiratory tree, allowing them to breathe in oxygen.
Because they scavenge the ocean floor, sea pigs are considered "living vacuums." And while they have very few enemies in the deep ocean, sea pigs still maintain a fairly potent defense mechanism: their poisonous skin.
The skin of a sea pig contains a toxic chemical known as holothurian, which is so poisonous that some fishermen in the Indo-Pacific use it to knock out fish in local reefs.
However, little else is known about these odd marine animals. Researchers have a difficult time studying these strange animals because they are unable to be brought up to the surface for examination. The sea pig is a delicate creature that is used to the high-pressure habitat on the ocean floor. They would effectively melt when out of the water.
As such, scientists are forced to observe the species from the surface using high-tech equipment such as remotely operated vehicles or ROVs.
