What is the dolphin's  outer skin covering?
147760
The core of a dolphin’s body is well insulated by a thick layer of blubber. Generally, a blubber layer is anywhere between 3/4" to 1-1 /4" thick. The thickness is related to the type of environment the dolphin lives in. Colder waters require a thicker blubber layer. The blubber is actually the modified 3rd layer or "hypodermis" of a dolphin’s skin. Skin is made up of three layers: an epidermis (top layer), a dermis (middle layer) and a hypodermis (bottom layer). The surface layer or epidermis of a dolphin’s skin is ten times thicker than any land mammal, and serves as protection against the elements. Additionally, the entire top layer of skin sloughs off every two to four hours, helping the dolphin stay streamlined, moist and while free of external attachments while traveling through the water.\n\nUpon close examination of a dolphin’s skin, micro dermal ridges are visible. Micro dermal ridges are small ridges that trap water molecules at the surface of the skin. This allows the dolphin to pass through its environment with less resistance because liquid moves more easily past another liquid than past a solid object. Micro dermal ridges allow a dolphin to travel more like a liquid through water with less resistance. A famous sail boat competitor used the idea of micro dermal ridges to his advantage to win the World’s Cup. He had Dupont design a skin for the bottom of his boat based on a dolphin’s micro dermal ridges. This technology increased his boating speed by a half-knot. Many wet suit companies use the principle of micro dermal ridges, as well.\n\nIn addition to micro dermal ridges, a dolphin has very pliant skin. When a dolphin reaches a certain speed while traveling through water, the typical smooth flow of water becomes more turbulent. A dolphin’s skin will actually ripple at accelerated speeds to counter the effect of turbulence as they travel through the water.
638413
The cells in your outer layer of skin absorb water and puff up.
745467
Dolphins do breathe air, but their skin/eyes/other stuff would dry out and eventually they would die
864207
Yes, it is called a wolphin. Part common bottlenosed dolphin, part false killer whale. I believe. Here's a link to be sure.
305663
whatt mahi mahi? a dolphin?
571640
Both dolphins and porpoises are mammals. Even though they both live in the ocean, they are not fish. They do not have breathing gills. They have lungs and breathe air. Both also give birth to live young and nurse those young. A mammal is also characterized by having the presence of hair: when dolphins and porpoises are small, there are small hair follicles. \n\nDolphins and porpoises belong to the same scientific order, Cetacea. This order includes all whales, even the great whales, to which both dolphins and porpoises are related. All cetaceans are completely aquatic mammals, have a streamlined body, a tail fluke, and a blowhole (which is what these air-breathing animals use to breathe). The dolphins and porpoises are also classified in the scientific suborder, Odontoceti, which are the toothed whales. All odontocetes also have the ability to echolocate, the ability to detect objects in their underwater environment using the echoes of a sound, much like sonar. \n\nPorpoises and dolphins are classified into two different families. The porpoises are in the family Phocoenidae and the dolphins are in the family Delphinidae. When separated at the family level, dolphins and porpoises are as physically different as cats and dogs.
193147
The hard, rigid outer covering of certain animals is called a shell. While many animals, particularly those that live in the sea, produce exoskeletons, usually only those of mollusks are considered to be shells. It is sometimes erroneously claimed that shells are made of chitin, but these are unrelated materials (except for their hardness and use as a covering by animals).\n\nThe shell is usually made of nacre, an organic mixture of outer layers of horny conchiolin (a scleroprotein), followed by an intermediate layer of calcite oraragonite, and then a layer of calcium carbonate (CaCO3) in the form of platy crystals.\n\nNacre is secreted by the epithelial cells (formed by the germ layer ectoderm) of the mantle tissue of certain species of mollusk. Mollusk blood is rich in a liquid form of calcium. In these mollusks the calcium is concentrated out from the blood where it can crystallize as calcium carbonate. The individual crystals of each layer differ in shape and orientation. Nacre is continually deposited onto the inner surface of the animal's shell (the iridescent nacreous layer also known as mother of pearl), both as a means to smoothen the shell itself and as a defense against parasitic organisms and damaging detritus.\n\n \nVarious seashellsWhen a mollusk is invaded by a parasite or is irritated by a foreign object that the animal cannot eject, a process known as encystation entombs the offending entity in successive, concentric layers of nacre. This process eventually forms what we call pearls and continues for as long as the mollusk lives.\n\nShells are very durable and outlast the otherwise soft-bodied animals that produce them by a very long time. Large amounts of shells may form sediment and become compressed into limestone. Shells that wash up on beaches are called seashells, and are collected by some enthusiasts
258028
http://teacher.scholastic.com/dolphin/about.htm
92408
Looks like a cephalopod.
503201
actually, dolphins are the only other animal besides humans who enjoy sex. i was watching the discovery channel and these nasty dolphins were raping a baby orca whale. i cried
403629
The Dolphin as a spices is billions of years old. So to answer your question they evolved from sea dinosaurs.
57828
The whale. It is indeed a mammal.
704627
Check a aquarium. Also, you can check the Internet and if you live near the coast, there is probably going to be some sort of research center nearby that would have people who know a lot of stuff about dolphins.\nCheck www.dolphins.org\nIt's a dolphin research center, I think.
804709
All marine mammals (whales, dolphins) have vestigial rear limbs (small pelvic bones) and they also have remnants of clavicles (collar bones). Therefore, the captured dolphin would represent a "mutation" whereby the bones had greater growth than normal, much like humans can have abnormal growth of the coccyx, looking similar to a tail. \nRemember - with evolution, once you lose something, you can't get it back ,so there isnt any way that you could get "reverse" evolution. Darwin wouldn't be "proud". Darwin would be more happy to think that he was no longer being ridiculed for his findings and that scientists were investigating our natural world rather than just assuming everything happened through divine intervention. Darwin would think this dolphin to be an interesting mutation and further provide evidence of the evolution of mammals. Evolution has no motive, it just happens due to natural selection and selective pressures, so Darwin would not think that something is being achieved by this and would simply see it for what it is.
517976
Dolphins might also have an itch, and that's the best way they can deal with it since they don't have hands.
950158
A dolphin's brain is approximately 1700 grams and a chimp brain is approximately 420 grams
574261
Reptiles breath through thier skin.