Crab

Crab is a beast of decapod crustaceans from Infraorder Brachyura, which is known to have a "tail" is very short (Greek: brachy = short, ura = tail), or the belly (abdomen) was hidden under the chest (thorax). Crab's body is protected by the outer frame of a very hard, composed of chitin, and armed with a pair of tweezers. Crabs and small crab is also included in the Infraorder Brachyura.

Crabs found in all oceans of the world. There is also a freshwater crabs and land, particularly in areas tropis.Kepiting varied in size, from crab beans, which only a few millimeters wide, until the crab Japanese spider, with leg spans up to 4 m.

True crabs have five pairs of legs; the first pair of legs modified into a pair of claws and are not used to moving. In almost all kinds of crabs, except a few only (eg, Raninoida), abdomen folded under the cephalothorax. Crab's mouth parts are covered by a flat maxilliped, and the front of the carapace does not form a long rostrum. Formed from crab gill plates are flat ( "phyllobranchiate"), similar to the gills of shrimp, but with a different structure.

Walrus

Walrus is a large mammal of the order carnivores that live in cool regions. At first, seals belonging to the suborder Pinnipedia, suborder category but now it has shifted into Superfamily category. Currently, the seal is inserted into the suborder Caniformia with families Odobenidae (sea bear / walrus), Otariidae (sea lions), and Phocidae. Recent molecular analysis has shown that the seal bears the closest relatives. Another hypothesis to say that the seals are polifiletik with true seals ancestors came from a animal like a beaver, while the other seal species originated from a common ancestor of animals such as bears, but recent molecular studies mentioned earlier assured that all types of seals is monofiletik, which is derived from a common ancestor.
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Seals are generally smooth-bodied and big enough. His body was well adapted to habitat akuatiknya, where they spent most of his life. As a hand, large front legs and shaped like fins, and his narrow back. Smallest seals, Arctocephalus galapagoensis ie weighs about 30 kg for adult size and length of 1.2 meter. Largest seal, which is the southern elephant seal (Mirounga leonina) has a maximum length up to 4 meters and weight of 2200 kg.

All types of seals are carnivores that eat fish, squid and other marine animals. Hydrurga leptonyx is probably the largest predators of the types of other seals, which eat a variety of animals from krill to penguins to other seals.

Dolphin

The dolphins are marine mammals are highly intelligent, but it was a complete natural system is very complex body. So much technology inspired by dolphins. One example is the skin of dolphins that can reduce friction with the water, so the dolphins can swim with a little water resistance. This is used by swimmers to design swimsuits that resemble the skin of dolphins.

The dolphins have a system that is used to communicate and receive stimuli called sonar system, this system can avoid objects in front of the dolphin, so avoid the collision. This technology is then applied in the manufacture of submarine radar. The dolphins are mammals. They live in the sea and rivers around the world. Dolphins and whales are kerebat Irrawaddy Dolphin. There are more than 40 types of dolphins.

Baby dolphin newborns will be brought to the surface by the parent to bias air. The dolphins need up to the surface to breathe to stay alive. Dolphins breathe through air holes located in the kepalnya. Her body is sleek and slim, very suitable for swimming. Dolphin Mother breastfeeding her child with a tasty milk and provides the energy for his son to a big fast. Every child dolphins always near its mother, so his mother could protect from danger. The dolphins are always keeping in touch with her son to grow even larger. Mother dolphins call their children with special whistles that they can identify with.

The dolphins live and work in groups called flocks. They often played together. A dolphin can not sleep well under water. He could drown. Therefore, he was half asleep some time in a day. Dolphins eat squid and fish such as fish gray mullet. Sometimes dolphins herd fish leads to easy arrest. The dolphins to find a way to send sound in water. If the sound of an object, the voice will be reflected back as echoes. Sometimes, the noise in the sea due to oil drilling can be confusing dolphin. They will have difficulty in sending and receiving messages.

Humans always interested in the story of dolphins. The Romans have made the image mosaic dolphin about 2,000 years ago. Now, people like to swim in the ocean with the animals as intelligent and friendly dolphins. The dolphins have to watch out for sharks that might attack them at any time. They protect themselves with teeth teeth, sometimes they use the beak as a ramrod. Humans can be catching lots of fish for the dolphins for food. Sometimes, the dolphins caught by fishing nets. They can not breathe on the surface, as a result they sink. When hazardous chemicals dumped into the sea, the waste can poison the food you eat dolphin. Construction of reservoirs on rivers and lakes drying, leaving little room for animals such as dolphins to live in Brazil.

The dolphins are classified as intelligent mammals. The dolphins could help humans, when the dolphins are trained, even the ring of fire they were able to breakthrough. Sea lions, species of primates, whales and dogs also includes an intelligent animal. Dolphins that are trained to perform a variety of attractions and they can also count, but the wild dolphins can not do many attractions. Today, dolphins and whales are rare, the dolphins and whales should be protected. Dolphins and whales have begun to be protected throughout the world.