Sea cucumber - Wikipedia
While thesea cucumber–pearlfish relationship has beenwell known for many years Theleopard sea cucumber grows to up to50 centimetreslong and the. A Theme from In Praise of Old Haiku, with Many More Poems and Fine Elaboration are not talking symbiosis, it injures the moray)! To return to our subject, the fish does not “Backing into its garage, a pearlfish parks inside a sea cucumber. There are over 1, species of sea cucumbers that can be found in oceans throughout the world. Studying sea cucumbers can be a good review of echinoderms. Except . The famous example is Pearl Fish. This is a good example of "Symbiotic Relationship", too! . Lesson 9: [Poem] Song of the Sea.
Butler suggests that their behavioral change is an adaptation to thwart the spread of a lethal disease, and that it may be the only known example of this sort of "shunning" in the animal kingdom. Even with their crushing claws, spiny swords, shield-like carapace, and of course, Super Soaker pee blasters, lobsters are not invulnerable to predators.
For those of you who like to eat the disgusting gooey green stuff inside a lobster's body, the tomalley, it is the liver and pancreas combined, which acts as a filter and can accumulate pollutants or toxins over time. It is probably best to forgo this rather questionable delicacy. Shape-Shifters The humble sea cucumber sits like a log on the ocean floor and may resemble its namesake from the garden or grocery store, but this creature is far from a simple lackadaisical lump; it is endowed with some very special abilities.
Sea cucumbers are tube-shaped and come in various colors, such as tan, green, or black, with bumpy, leathery skin, growing to a typical length of about 15 to 25 centimeters 6 to 10 inches. That's the garden-variety sea cucumber. In fact, there are more than a thousand described species, and many of them are more of a nature-gone-wild version of their fruit look-alike.
That's right, cucumbers are in fact a fruit, not a vegetable — one never knows what interesting fact will turn up when researching a book! Sea cucumbers may be dressed in psychedelic hues of electric blue, vivid purple, or shocking red, and sport spikes or frills or appear almost furry. The giant red or California sea cucumber is the largest of its kind, reaching a monstrous length of nearly a meter 30 inches.
My favorite is the chocolate chip sea cucumber, covered with tan skin folds resembling that of a shar-pei puppy and speckled with black-brown spots. Sea cucumbers are found worldwide, ranging from the deep sea to shallow shores, and can live in mud, in sand, on rocks, or in coral reefs. They attach to the bottom or move about sluggishly on five rows of small tube feet, which are extended or retracted using an internal hydraulic system of seawater.
For sea cucumbers life is all about finding yummy particles of organic matter.
Some sea cucumbers filter seawater to acquire these tasty bits; others use mucus-covered tentacles that they raise up or sweep over the seabed. They bring their tentacles into their mouths, lick off the entrapped particles, and then re-release their sticky collectors to gather more food.
There are also some slurpers; these sea cucumbers crawl over the seafloor slurping in sand or mud to sift out the organic matter. It is when threatened that the sea cucumber reveals its truly odd nature. Sea cucumbers are real-life shape-shifters; if predators near they can morph their skin from hard and lumpy into something a bit less appetizing, akin to a gelatinous slime. When danger looms they literally turn to mush!
Sea cucumbers have another very effective and rather disgusting means to deter predators: Some sea cucumbers eject a sticky spaghetti of white tubules, while others release their actual internal organs. A predator such as a fish or sea star may become entangled in the slimy mass or be distracted long enough for the sea cucumber to slowly crawl away. Imagine the shock on a mugger's face if on demand you could let loose of your insides.
Amazingly, not only does the sea cucumber survive, but in just three to five weeks it also regenerates its internal organs. Unless you like a handful of guts, it is unwise to pick up or harass a sea cucumber. Some sea cucumbers also exude a toxin, which can leave aquarists baffled when they add this seemingly peaceful creature to their tank and a mass mortality ensues.
Relatively recent research has also discovered that in the deep ocean there are strange, translucent sea cucumbers that can swim—well, sort of swim; actually it looks more like flying.
Pearlfish and Sea Cucumber Symbiosis
This adaptation is thought to allow them to more efficiently find food in the deep sea, where dining options are often quite limited and may come in periodic windfalls from above. I queried a group of graduate students studying marine biology at the University of Miami's Rosenstiel School of Marine and Atmospheric Science about what creature they thought was the oceans' most unusual.
One young woman responded immediately: The pearlfish's association with the sea cucumber hinges on the fact that the sea cucumber breathes through its butt. Water flows in through the "back entrance" and washes over the animal's respiratory organs, wherein oxygen is consumed and carbon dioxide is released.
The water then flows back out the way it came in. The tiny pearlfishes have handily evolved the ability to detect the chemical signature of the sea cucumbers' respiratory outflow. This becomes useful for a pearlfish after a night of foraging, when seeking a protective daytime shelter. Like a heat- I mean butt- seeking missile, the pearlfish uses its detecting skills to find a sea cucumber and enter via the backdoor.
Its hiding spot within the sea cucumber comes with an added benefit; it is already well stocked with provisions. The pearlfish nibbles on its host's respiratory or reproductive organs. Understandably, some sea cucumbers are not willing hosts and will eject their respiratory or digestive organs to deter the sneaky little fishes.
One species of sea cucumber goes even further, as it has evolved a deterrent: Why They Matter Sea cucumbers, hagfishes, and lobsters all play important roles in the ocean ecosystem and have both obvious as well as more subtle connections to our everyday lives. Within the sea's web of life, hagfishes and lobsters play duel roles, as both scavengers and predators.
As predators, these animals keep prey populations in check and remove the weak or sick from the gene pool. As consumers, they also transfer energy in the form of carbon organic material up through the ocean ecosystem.
Lobsters and hagfishes also provide sustenance for the organisms that eat them, such as fishes, sharks, or marine mammals. Sea cucumbers provide nourishment for other organisms as well, including sea turtles, sea stars, some crustaceans, and many fishes. As scavengers, the lobster, hagfish, and sea cucumber are part of the oceans' cleanup crew. The hagfishes are probably the best of the bunch, providing a rapid and effective means of cleaning up the dead and rotting of the sea, anything from a ton whale to the discards from an industrial fishing ship.
In fact, the practice of dumping fishery discards, the unwanted or too small, is believed to have fueled an increase in some hagfish populations. Sea cucumbers tidy up both the water and the sediments. Where filtering sea cucumbers are abundant, they play an especially important role in promoting water clarity and quality.
Slurping sea cucumbers strain organic matter from the sediments. Much like earthworms in a garden, sea cucumbers and other creatures that burrow or feed within the sediments of the seafloor also help to keep the bottom aerated and well mixed.
Food For most of us, lobster certainly sounds more appetizing than a nice plate of hagfish or sliced-up sea cucumber. In Asia, however, people eat both hagfishes and sea cucumbers. Imagine the eel-like hagfish skewered in s-shaped folds and then roasted-slime hag on a stick.
Or how about a nice dinner of braised sea cucumber or a side order stir-fried in black pepper sauce? The fermented viscera of sea cucumbers, aka pickled gonads and intestines, is considered a delicacy in Japan.
People tell me that sea cucumber is rather plain tasting, and that much like tofu it sucks up the flavor of whatever it is cooked in. One culinary advisor even suggests that no gourmet should go without experiencing the succulent jelly-like texture of a sea cucumber. I have to question such advice on a whole number of levels. When it comes to more popular seafood, the lobster is a tasty icon. The variety of ways in which it is served seems endless — the classic steamed lobster, the lobster roll, baked, stuffed, on the grill, covered in a rich cream sauce, stir-fried, poached, and now, as a means to make mac and cheese an epicurean delight.
Lobsters are sold throughout the world; they can even be shipped directly to your home. It is a must-have for luxury hotels, restaurants, and cruise lines. Lobster meat is also low in fat and cholesterol — it's the butter for dipping that will go to your waistline and block your arteries. But lobster has become more than just a simple food; eating this ocean animal has become synonymous with being able to afford the best and an important part of a cultural, regional culinary experience.
No matter how it is cooked or served, lobster is about much more than just food. The state of Maine accounts for most of the lobster caught in the United States, with landings in valued at more than three hundred million dollars.
Dr. Ellen Prager — Sex, Drugs and Sea Slime: The Oceans' Oddest Creatures and Why They Matter : NPR
A drive along Maine's coast is all that is needed to see the importance of lobster to the region. Images of the clawed crustacean are everywhere, on signs for roadside seafood shacks and fancy restaurants or hotels, decorating windows, doors, and mailboxes. In this area of the world, lobsters are like hot dogs to baseball or chips to salsa; they are the underpinning of tradition, culture, and tourism.Sea cucumber with crab in its butt
People from around the world travel to Maine to partake of lobster pulled fresh from the sea. Thousands of people are employed directly and indirectly by the industry in fishing, processing, marinas, shipping, hotels, souvenir shops, and in restaurants. And here, lobstering is serious business: For the fishermen involved it is a way of life that has passed from one generation to the next and which they fiercely protect.
I was fortunate enough in to spend a day out on a lobster boat off the coast of Maine with Tommy, a seventy-eight-year-old fisherman. As he pulled his traps, I was the bander of the lobsters' claws and helped with rebaiting. It was a rainy, rough, windswept day on the seas, which in no way deterred Tommy or his love for the job.
I asked what kept him going day in and day out, hauling hundreds of traps each day for so many years. He said it was simple for him and many others like him; it was a love for the sea and a curiosity to see what each trap would reveal.
Midway through the day I understood his calling, peering eagerly over the boat's rail as each trap was hauled up. Would there be a fish, crabs, big lobsters, small lobsters, or females with eggs that needed to be thrown back to preserve the population?
It was an endlessly fascinating and productive day. Hopefully, lobsters will continue to provide for this ocean-going, ocean-loving way of life, one that so defines and supports coastal Maine.
Additional vessels surround the respiratory trees, although they contact them only indirectly, via the coelomic fluid. Phagocytic coelomocytes, somewhat similar in function to the white blood cells of vertebratesare formed within the haemal vessels, and travel throughout the body cavity as well as both circulatory systems.
An additional form of coelomocyte, not found in other echinoderms, has a flattened discoid shape, and contains hemoglobin. As a result, in many though not all species, both the blood and the coelomic fluid are red in colour. However, because of their posture, they have secondarily evolved a degree of bilateral symmetry. For example, because one side of the body is typically pressed against the substratum, and the other is not, there is usually some difference between the two surfaces except for Apodida.
Like sea urchinsmost sea cucumbers have five strip-like ambulacral areas running along the length of the body from the mouth to the anus. The three on the lower surface have numerous tube feetoften with suckers, that allow the animal to crawl along; they are called trivium. The two on the upper surface have under-developed or vestigial tube feet, and some species lack tube feet altogether; this face is called bivium.
Those of the order Apodida have no tube feet or ambulacral areas at all, and burrow through sediment with muscular contractions of their body similar to that of worms, however five radial lines are generally still obvious along their body.
These are highly modified into retractile tentaclesmuch larger than the locomotive tube feet. Depending on the species, sea cucumbers have between ten and thirty such tentacles and these can have a wide variety of shapes depending on the diet of the animal and other conditions. Endoskeleton Echinoderms typically possess an internal skeleton composed of plates of calcium carbonate. In most sea cucumbers, however, these have become reduced to microscopic ossicles embedded beneath the skin.
A few genera, such as Sphaerothuriaretain relatively large plates, giving them a scaly armour.
Pearlfish and Sea Cucumber Symbiosis
The body of some deep water holothurians, such as Enypniastes eximia, Peniagone leander and Paelopatides confundens,  is made of a tough gelatinous tissue with unique properties that makes the animals able to control their own buoyancy, making it possible for them to either live on the ocean floor or to actively swim  or float over it in order to move to new locations,  in a manner similar to how the group Torquaratoridae floats through water.
Holothurians appear to be the echinoderms best adapted to extreme depths, and are still very diversified beyond 5, m deep: For this reason, one such area in Fiordland is called the strawberry fields.
Most of them have specific swimming appendages, such as some kind of umbrella like Enypniastesor a long lobe on top of the body Psychropotes. Ruminants and Micro-organisms In the animal world a good example of mutualism is that between a ruminant and the many millions of micro-organisms which live in its rumen.
You will remember that a ruminant, such as a giraffe, has a sac called a rumen situated just before the stomach in its gut. When a ruminant swallows its food, which is vegetation, the food goes into the rumen.
Here the plant material is digested by the microorganisms. The micro-organisms make a special chemical which can break down the plant cells but the ruminant is not able to make this chemical. The micro-organisms digest the plant material for both themselves and the ruminant.
In return the ruminant provides them with a constant supply of vegetation as well as a safe and a warm place in which to live. Often, mutualism joins forces in such a way that humans, observing these interactions, see in them object lessons, or stories illustrating the concept that the meek sometimes provide vital assistance to the mighty. One example of this is purely fictional, and it is a very old story indeed: Aesop's fable about the mouse and the lion.
In this tale a lion catches a mouse and is about to eat the little creature for a snack when the mouse pleads for its life; the lion, feeling particularly charitable that day, decides to spare it. Before leaving, the mouse promises one day to return the favor, and the lion chuckles at this offer, thinking that there is no way that a lowly mouse could ever save a fierce lion.
Then one day the lion steps on a thorn and cannot extract it from his paw. He is in serious pain, yet the thorn is too small for him to remove with his teeth, and he suffers hopelessly—until the mouse arrives and ably extracts the thorn. The oxpecker, of the genus Buphagus, appears in two species, B. It feeds off ticks, flies, and maggots that cling to the rhino's hide. Thus, this oddly matched pair often can be seen on the African savannas, the rhino benefiting from the pest-removal services of the oxpecker and the oxpecker enjoying the smorgasbord that the rhino's hide offers.
One of the most intriguing is the arrangement that exists between ants and aphids, insects of the order Homoptera, which also are known as plant lice. In return, ants protect aphid eggs during the winter and carry the newly hatched aphids to new host plants.
The aphids feed on the leaves, and the ants receive a supply of honeydew. This particular mutualism involves the butterfly Glaucopsyche lygdamus when it is still a caterpillar, meaning that it is in the larval, or not yet fully developed, stage.
Like the aphid, this creature, too, produces a sweet "honeydew" solution that the ants harvest as food. In return, the ants defend the caterpillar against parasitic wasps and flies.
It is a classic instance which can be noticed in stony corals regions of Oman sees; it is the symbiotic relation between Sea anemones and Clownfish. The answer is that clownfish are protected by the mucous substance which covers their body and acts as an absorbent layer and reduces severity of stings.
In this manner it gets a safe place to live; and while not appearing to gain any benefit from the relationship, the cucumber is not harmed.
When approached by a predator it waves these around presenting the stinging tentacles so as to deter the marauder.
The anemones benefit from the small particles of food dropped by the crab during feeding. In some cases, notably with many of the Wrasses, it is just the juvenile of a fish species that is a cleaner, while the mature fish progress onto a diet of larger invertebrates.