Intelligent marine mammals

Today we feature yet another unique marine mammal which is facing serious problems due to us humans. It is the lovable dolphin, a cousin of the famous dolphin

named Flipper in the popular TV series which was telecast sometime ago. Let's check out the lifestyle, habits, and physical features of these cute-faced marine creatures who are known to be very intelligent when compared to most other marine animals,These intelligent mammals are found in our country too. There have been several reports of dolphins being caught in the nets of our fishermen and being injured or killed, eventually.

Dolphins belong to the family Delphinidae, which is the largest and most diverse family of the cetacean order and include 26 living species. Several species of dolphins are found in the Hawaiian waters. However, it is not only in this area that they are found. Dolphins inhabit the oceans worldwide, mostly in the shallower seas of the continental shelves. The family Delphinidae is considered a relatively recent addition to the cetacean family, having evolved more recently than the others of its family. Most species of dolphins are larger than porpoises, with the males usually being larger than the females.

The name is originally from the Ancient Greek word (delphs; "dolphin"), which was related to the Greek word (delphys; "womb"). The name can therefore be interpreted as meaning "a 'fish' with a womb.

Dolphins are extremely social creatures and they depend on their social relations even while hunting as well as in reproduction. Unlike the humpback whales and other species of baleen whales, dolphins live in tightly knit groups - smaller groups are called pods which range between two to forty members, and larger groups called schools or herds. These groups can include more than one species, because each species has its own niche. Spotted and Spinner dolphins are constantly found living in such groups. Researchers believe that this is possible because spotted dolphins usually prey on larger creatures closer to the surface, while the Spinner dolphins tend to feed in deeper waters on smaller prey.

They are carnivores, maintaining a diet of mainly fish and squid.

Dolphins are some of the most intelligent animals, and their playful behaviour and friendliness have made them very popular among humans.

Dolphins are adapted extremely well to the sea. Even though their hind limbs have disappeared, their front limbs have developed into flippers. Their powerful tail is the main instrument for them to move forward. Dolphins possess a distinct beak. Their teeth are conical in shape Dolphins usually breathe through what is called the blowhole on the top of their heads. They can empty their lungs and refill them in one fifth of a second. As they breathe, the air leaves the blowholes at speeds of over 100mph. But how do they know when to open their blowholes, because if they open them in the water, they could die?. Well, as we know by now, all creatures are built with special features needed to help them survive in the habitats they live in. So, dolphins too have such special features and they know exactly when the surface is near so that they could open their blowholes. Water in a dolphin's blowhole will definitely drown it, therefore powerful muscles close the blowhole as soon as it dives under the water after taking in a breath of air.

Its eyes produce a slippery liquid which protects the dolphin from unknown substances as well as the water. Like whales the dolphin can only sleep with one brain resting at a time or else it can drown. Dolphins take short cat-naps, floating just below the surface, and then slowly rising to breathe, because breathing is a voluntary procedure for the cetaceans. Often dolphins are very active during night time, and for some, this is their main feeding time.

The skin is completely smooth unlike that of most other mammals, and this allows the dolphin to move faster in the water.

Their bodies are built in a way they could swim at high speeds through the water, and an example of this is their ears. Dolphin's ears are barely noticeable marked only by a small hole just behind the eye. In a bottlenose dolphin, the ear is about 5-6 cms behind the eye and only 2-3 mm in diameter.

Because dolphins feed on schools of prey, most species have developed communal and cooperative hunting practices, as searching for food as a group is more efficient than searching individually. The exception to this rule is the river dolphin who usually feeds on individual prey on the river bottom. They are often found living alone or in very small groups.