If you happen to check the computer screens of most people, you will find that several of them will have pictures of dolphins as their wallpaper. Dolphins are interesting, highly intelligent marine mammals that belong to taxonomic order Cetacea. They are part of the toothed whale family, which include pilot and orca whales. The word dolphin originally came from the Greek word delphís, which is closely related to another Greek word delphus, meaning “womb”. The word dolphin can thus be taken to mean “a fish that has a womb”.
Dolphins are found all over the world. Most species live in shallow waters of temperate and tropical oceans. However, five species live in rivers.
There are approximately forty dolphin species all over the world, mostly found in shallow sea waters. Some species are also found in rivers. The color varies among different species, but most are gray in color, with the backs being darker than the rest body parts.
Dolphins consume are carnivores and they consume a variety of prey, with fish, crustaceans and squid are the most common prey. However, orcas and killer whales also feed on other sea animals, with orcas being known to hunt other large mammals on some occasions. They hunt in a group by surrounding a school of fish, trapping them and then taking turns feeding on the trapped fish. Other feeding methods such as chasing prey into shallow water for an easier catch or following whales, seabirds and fishing boats to feed on the fish they scare also exist.
Dolphins are agile and have a playful behavior, which makes them favorite animals for people who love to watch wildlife. Most people especially love watching them leaping out of the water.
They are very social, and they live in groups called pods. One pod is comprised of about five to several hundred individuals depending on the species, environment and availability of food. In environments where there is a lot of food, several pods can join together to form a superpods of even more than 1,000 individuals.
They have also been found to exude an unselfish behavior. While membership to a pod is not rigid, they can form strong bonds, protecting the injured individuals and nursing them back to health. Some species have also been observed guiding other stranded sea mammals back into the ocean. Other species have been seen protecting swimmers from sharks by surrounding them or charging at sharks to scare them away.
Dolphins mate throughout the year, though in some places the mating season usually peaks during spring and fall seasons. The gestation period of these mammals is around 9-17 months, depending on the species. During birth, the female separates from others in her pod and goes close to the water surface where she gives birth.
Dolphins give birth to one calf. However, some can give birth to twins, but this is rare. When a calf is born, the mother must take it above the water surface to breathe, which is the reason they give birth close to the water surface. The mother then nurses the calf for a period of about 11 months to 2 years.
One of the things that make these animals unique from other sea mammals is their senses. Most species have an acute eyesight, when both in and out of water. They also have a very great hearing ability, and they can process and hear sound frequencies of over ten times the upper limit of a human ear. The hearing ability is used for echolocation, biological sonar that is found on each dolphin. It is believed that their teeth act as antennae, which they use to receive incoming sounds from objects in the water, and then use these sounds to pinpoint the exact location of the objects. Echolocation is mainly used to hunt for their prey.
As already mentioned, dolphins are highly intelligent animals, and are considered one of the most intelligent mammals on earth. They are also very beautiful, and most around the world use dolphins large pictures to decorate their houses or as desktop wallpapers. See our gallery of pictures of dolphins …