Dolphins or Dolphin
Dolphin, common name that receives any from some species of cetáceos of the family of the Delphinidae. Also called dolphin. They are animal of round head great e, with the robust front, the dorsal wing bending and developed and the general coloration of the dark body. They can dive sufficient the depth and if they feed over all of squids. They are animals that can identify ones to the others in individual way. As other cetáceos, they use the ecolocalização to investigate the outskirts and to dislocate themselves in its environment.
Scientific classification: Globicephala sort, family of the Delphinidae, subordem of the Odontocetos, order of the Cetáceos.
Orca is member of so great greater of the family of the dolphins or dolphins and, possibly, the cetáceo who present ampler world-wide distribution. It has a great, situated dorsal wing in average position throughout the back. Its feeding consists of fish, sea squids, birds, pinípedes and other cetáceos. These animals tend to cooperate between itself in the hunting, in special when if they feed of animals of hot blood, as penguins. They use a ecolocalização system that consists of the emission of similar sounds the small dry blows high-frequency, that they strike in its canine tooth or other objects, and whose echoes allow them to locate the canine tooth. They are communicated enters itself by means of the emission of a fast series of dry blows that sound as tow-car.
Scientific classification: family of the Delphinidae, subordem Odontocetos (whales provided with teeth), order of the Cetáceos. It is the classified species as Orcinus calculates.
The dolphins of the oceans
This is without a doubt the biggest family of dolphins, is more than 12 different species. Many of the oceanic dolphins pass most of the time, dislocating themselves in the ocean, covering vast areas of sea, far from the coast. Many species are distributed by the World. Some of these species, 0ccasionally, cover the rivers and live side by side with the true dolphins of river. The oceanic dolphins, typically bigger that of river, differ in agreement size the species. The oceanic dolphin of so great minor has 1,4 the 1,8 length m and weighs between 36kg and 45kg. The bigger oceanic dolphin is Orca, that measures 9.8m more than and weighs about 5000Kg, being bigger of what some species of whales. The factors that these dolphins threaten are several and vary of species for species. The ones that lives close to the coast suffer the effect from the pollution, the danger of the navigation of boats and the nets of fish. Those that live far from the coast, also have problems… most serious of all are the nets of fish of the tuna, since the dolphins travel many times with this fish. We are unaware of the population tax of these mammals, however exactly that a group of these dolphins is threatened, it always has another group that if keeps healthful!
The dolphins of the rivers
The river dolphins are adapted for the cool water, and for this reason, they obtain to live constantly in the rivers. Its bodies are flexible and ideal to pursue its canine tooth, some of the times in sufficiently narrow rivers and of winding volume. These mammals hunt alone or in groups of 2 or 3, and feed themselves basically of fish. These dolphins possess a long tooth line, that the aid to chew the fish, some possess molar proper to jam small shellfishes. Three of the species of river dolphins are almost blind, and they only count on its sonar to find food and to sail. The main threat for these dolphins, is the pollution of the rivers where they live. In many of the countries where these mammals if find - China, India, Pakistan and South America - the population was taking possetion itself of lands to the return of the rivers, and removed most of its resources, however the dolphins survive only for the beliefs of these same people. These mammals are considered legends, and omens.
Turtle, common name of certain reptiles (quelônios) that if they characterize for one carapaça rigid, that recovers its internal agencies. They are forms of very old lives. The identified fósseis oldest as turtles retrace to the Triássico, have one 200 million years. Today, they exist about 360 species, terrestrial and aquatic, in the whole world. In Brazil, it has 40 species approximately.
The order the one that belongs the turtles if divides in two subordens: the first one understands species capable to inside retract the head for of the shell with a movement by telescope (to strain and to shrink) the neck; e second includes the water species candy, that hide the head folding the neck for a side. In the majority, they are adapted hábitats of terrestrial water candy or and a small group, to the life in the sea.
The superior part of carapaça also receives the name from espaldar; the inferior, plain part, is called chest. The structure and the size of carapaça and the chest vary of a species for another one.
Typically, carapaça of the turtles is formed by two layers: interior, óssea one, whose sections are called plates, and one superior, córnea, formed for the calls shields. Although she is rigid, carapaça of the turtles is a very sensible structure, had to the great number of nervous terminations that contains.
Of the eight species and subspecies of turtle-navies, five costumam to frequent the coasts Brazilian. They are: turtle-green; cabeçuda; turtle-of-leather; turtle-of-comb; e turtle-bastard. All are in the official list of extinguishing animals at risk, although the work developed in the Tamar Project (Turtle-Navy Project), that, operating in the coast of the Bahia since 1979, already it returned to the sea 2 million younglings. It enters the quelônios of water candy, is part of the list cágado-of-hogei, endemic of the state of the River.
In the Amazônia, even so it does not have no turtle considered in risk situation, is great the pressure on the Podocnemis species expansa, Podocnemis unifilis, Geochelone denticulata and Teltocefalus tumerilianus, due to hunting and to the egg collection.
The turtle alaúde is the greater of the seven species of sea turtles. Kg arrives to weigh 540. It is differentiated of the other aquatic and terrestrial turtles for its incapacity to retract the head for inside of the hoof and for the modification of the legs in paddles. It is only fed of jellyfishes.