Dolphins interact with humans since their existence is known. Since then, its most dangerous predator, and the only one that has drastically reduced its population is the man. Although we all agree that dolphins are wonderful, very intelligent and kind, we remain a great threat to them.
Characteristics, food, origin, habitat, species and reproduction of the dolphin
The dolphin, also called Oceanic Dolphin, is an amazing mammal that is part of cetaceans, and is considered one of the animals with more intelligence on the others. It belongs to the family of the Delphinidae and is located in the order of the odontocetes (sea animals with teeth) in this group also enter the whale, the sperm whale and the porpoise.
Similarly, dolphins have a common kinship with platanistoideos, generally known as river dolphins. For a time it was assumed that the cetaceans came from a species of terrestrial placentae already extinct, called Mesoniquios, however, at present it has been possible to show that the Dolphins have an ancestral past in the Artiodactyla. In the Miocénico period, the odontocetes appeared on the planet, and by that time the primitive dolphins were not very different from the current specimens.
Generally, the dolphins measure between one and nine meters long.
Its weight ranges from 70 to 110 kilos. The color of his body is grayish.
Because of their elongated body these animals are usually extraordinary swimmers, and through the hole that has on the top of their head, they are able to breathe out of the water.
They can reach depths of up to 260 meters.
Thanks to the caudal fin can be moved at high speed under water, on the other hand, use the pectoral fins to direct the movement, they can move at will.
The dolphins have a slender and elongated snout that can contain between 20 and 50 pieces of teeth, they are called: dentition Homodonta, since each of their teeth are exactly the same.
They are often very sociable, playful in spirit and have a lot of energy thanks to their developed brain that has evolved in a surprising way over the years have the ability to understand and communicate with each other.
They have their own vocabulary, through studies it has been proven that they use compound phrases by coupling syllables and consonants. This vocabulary is based on the emission of different tonalities of sound to say what they want.
These mammals are able to express among themselves feelings of affection, communicate when they are in danger and even when they need help to do something in particular.
The reproduction of dolphins is based on two stages: courtship and mating, this characteristic is common in all subspecies. Ovulation of females usually occurs about four or five times a year, but this may vary depending on the temperature of the water, how well they feel in the habitat where they are and other outside conditions.
The dolphins are usually bisexual and polygamous, so they are not tied for life with a specimen of their kind of opposite gender. Like any mammal, the Dolphins copulate through the penetration of the male to the female, a process that occurs during the spring, twelve months after copulation, the female will have a gestation period of 10 to 18 months and will give only a single calf, then should Wait until two years to conceive again.
Something characteristic in the dolphins during the reproductive stage is that they are very respectful of themselves, the younger ones let choose the female first the male chief Alfa without coming confrontations between them. The longevity of these specimens is 29 to 60 years of age.
Currently, some 46 types of dolphins are recognized, all of them included within the suborder of the odontocetes cetaceans. Since they have existed more than 30 million years ago, a process of speciation has been given with very different varieties in anatomy, habitat and behavior. Here we will mention the most representative types of dolphins within this family according to their gender.
Common coastal Dolphin, genus: Delphinus.
Common Oceanic Dolphin, genus: Delphinus delphis.
Bottlenose dolphin, genus: Tursiops truncatus.
Spotted Dolphin, genus: Stenella frontalis.
Dark Dolphin, genus: Lagenorhynchus obscura.
Southern Dolphin, genus: Lagenorhynchus australis.
White Dolphin, genus: Albirostris Lagenorhynchus.
Pink Dolphin, Genus: Inia geoffrensis.
The dolphin can be regarded as a universal mammal as it lives in all the seas of any existing ocean, with the exception of the polar oceans. Because they are so intelligent animals they choose to live in a social way with others of their same species creating numerous populations that come to surpass the thousand specimens for each group. Dolphins are also usually located in river areas.
However, there are oceanic and marine dolphins, although in general terms it is a species that widely inhabit the world, it is always conditioned by basic necessities such as food and safety.
One finds the river dolphin (Platanistoideo), it is very common in the mouths of the rivers and river courses. However, this species does not live in all rivers, although it is normal to find it in regions of India such as Ganges and in South America, specifically in the Amazon.
Among the most common foods are small fish and generally squid, easy-to-digest crustaceans that easily devours. They also usually eat cod or herring, mackerel, sardines, crabs. Commonly, small animals that can then digest as they do not chew food.
The daily intake of food of the dolphins implies a consumption of approximately 10% of its own size, being a very restless animal, spend enough energy, that is why they usually ingest fish and crustaceans of high energy value.
On the other hand, the offspring feed only on the milk supplied by the mother, which contains all the nutrients needed in both proteins and fats. Later, as the calf grows, he will walk away from his mother to find his own food.
Its main food is carnivorous, they are excellent hunters so the capture of prey to be able to feed is the order of the day. The dolphin hunting system is very interesting, they are even capable of hunting being more than 60 meters deep, since, despite the absence of light, they are usually guided by a technique of geolocation very developed that allows them even to detect the Size of the dam.
If on the one hand, the orca used to hit the ice banks to disorient and make their prey lose balance and make them fall into the sea, dolphins use employ more practical and ingenious methods.
For example, when there is a shoal of fish, the dolphins will swim around them at a certain speed to make a kind of sphere, where the fish will be caught without being able to leave. At different intervals, each of the Dolphins will cross this «sphere» to catch the fish they can, while the other dolphins continue swimming around.
Another technique used is aquaplanning, where they push their prey to surface water to be able to submit them without any problems. Another widely used hunting maneuver is the so-called mud curtain, this technique is to drag the prey to surface waters, specifically to the edges where a mud curtain is created and it prevents the prey from getting out or moving easily. The dolphin is an animal with many skills and hunting is one of them.