|What are some of the most interesting life forms found in the deepest parts of the ocean?
|Question Date: 1998-03-04|
Here are some websites that will direct you to neat pictures of deepsea animals. I think the neatest animals are the gelatinous animals, jellyfish and ctenophores, and the bizarre and scary looking fish that live down deep. Read about bioluminescence on the bioluminescence webpage I've given you second on the list. Almost every single organism that lives in the deep ocean (where there is no light at all) can produce bioluminescence, so it is very important to all those animals down there. I study bioluminescence here at UCSB, so you can email in more questions about
bioluminescence, if you have any. The other neat group of animals is cephalopods, which are squid and octopuses. There are giant squid that live in the deep ocean and some very strange looking other squids and octopuses. You can just imagine all the weird looking creatures that evolved in an environment that is pitch black all the time, very cold, where there are no boundaries (no bottom or sides) and very little food.
Because of the food limitation, many deep sea creatures have to either migrate large distances to obtain food or live without food for up to a year! The other factor in the deep sea to consider is pressure. Have you ever tried to lift a 5 gallon jug of Arrowhead water? It's pretty heavy, right? Imagine how heavy about 2000 of those 5 gallon jugs must feel like! That is what those animals that live in the deep sea have to deal with-living under extreme pressure. This is another force that has caused some bizarre life forms to evolve in the deep.
I think one of the most amazing species is the worm-like one that lives near thermal vents.These organisms don't eat plants or animals and they don't use photosynthesis. They get their energy from breaking down the chemicals released from the vents. They live at extremely high pressures and are basically unlike anything else on Earth.
There are some little creatures that live on thermal vents (undersea volcanoes). They are not plants (they don't do photosynthesis) and they don't even eat other creatures. They get their energy and food directly from the heat of the vents and the chemicals pouring out of them. This makes them different from any other life on earth, because all other life gets its energy from the sun. These creatures are totally disconnected from the normal ecosystem.
Question: In what sense does all other life get its energy from the sun? If the sun disappeared tomorrow, what would happen to us? What would happen to these thermal vent creatures?
Some of the most fascinating creatures that live near "Black Smokers" (vents in the deep ocean) are a type of tube worm that can actually use hydrogen sulfide as a spurce of energy. Bacteria living near these vents also use H2S. You can read about these creatures if you log on to UCSB's website, then link to the Department of Ecology, Evolution and Marine Biology and also the Marine Science Institute. Dr. Jim Childress here studies these vent creatures.
Ah, the deepest part of the ocean!! In general we think of the deepest parts of the ocean to be the Abyssal Plain (2000-6000 meters) and the deep sea trenches such as the Marianas Trench which is 11,022 meters. Remember here in the Abyss there is no sunlight, the sea water temperature is between 32 & 38 DF and the pressure is about 3 1/2 tons per square inch! Mount Everest would have over a mile of water above it if were dropped into the deepest part of the Marianas Trench. So as you can imagine any animal that lives here is an interesting one! A few of the more interesting ones to me as a Marine Biologist are: A bizarre octopus of the Abyss (Opistoteuthis extensa), the ghost sharks or (Chimaeras) and of course all the bizarre deep sea fish such as the Big Mouths, Gulpers and Deep-sea angler fish. If you would like to learn more about the Abyss check out the book "Abyss The Deep Sea & the Creatures that live in it" By S.C.. Idyll
I can't tell you about the creatures in the deepest, deepest parts of the oceans but I can tell you about a few of the ones in a very special place in the deep ocean. Imagine yourself in small submarine only big enough to fit three people and you only have a small porthole to look through to view the water around you. You sink through the blackness of the cold water for an hour and a half to a depth of 2500 meters or about a mile and a half. You have reached your destination along a part of the global mid-ocean ridge system, a chain of undersea volcanoes which creates the oceanic crust.
You turn on the lights of the submarine to find a garden of life before you, white tubes with red tufts at the end, white crabs scurrying across the black seafloor, white eel-like fish darting out of the way of the sub. In the middle of all this you notice a tall chimney-like rock with a black smoke rapidly escaping. What you have found is a hydrothermal vent. What do you think hydro-thermal means?
What you have here is extremely hot water squirting out of the seafloor. The heat comes from the volcanic activity along the mid-ocean ridge. The water is black when it comes out because there are minerals in the water that become solid when they hit the cold ocean water and make the water cloudy. So what does this have to do with the animals??
The animals I'm going to describe to you depend on the hot water that is escaping from the seafloor. One of the materials that is in the water is hydrogen sulfide (H2S). There are bacteria that use H2S as food and energy. They are like plants that use sunlight and carbon dioxide to grow, they are photosynthesisers. These bacteria are chemosynthesisers, they use chemicals to live. They are the base of the foodchain in these hydrothermal vent communities. The crabs and shrimp eat the bacteria, the mussels and clams filter in the bacteria but what about these long white tubes?
Imagine a long while tube about an inch in diameter but is 5 or 6 feet long with a red tuft coming out of the end, this is a giant tubeworm often called Riftia. If you touch one the red tufts with the arm of the submarine it will disapear into the tube. These creatures have a special relationship with the bacteria. Inside the tubeworm lots of these bacteria live. The tubeworm collects the H2S from the water then takes it to the bacteria inside of it. The bacteria use the H2S to live and the tubeworm gets as food what the bacteria makes. It's like how we grow and eat plants. There is a special name for this kind of relationship, it's called a symbiontic relationship where each animal helps the other to survive. Oh, look at the time, you need to return to the surfice before you run out of air and power in the submarine. The pilot drops the weights that keep the sub at the bottom and you slowly ascend to the surface. I hope you enjoyed your brief journey into the depths of the ocean and I hope you learned a little along the way. If you are interested in these creatures or hydrothermal vents then I encourage you to find out more about them. Good luck with your science adventures!
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