Hobbies And Interests
Baleen Whales
Cetaceans are divided into two smaller groups and the first are baleen whales. These whales have plates that act as filters in their mouths, rather than teeth. They draw water into their mouths and then separate the plankton from the water by pushing it through their plates. Different species of whales feed on different sizes of prey according to how wide the gaps in their baleen filters are. In this way, they don't all compete directly with each other. The Grey whale, Humpback whale and Blue whale are all examples of baleen whales.
Toothed Whales
Toothed whales have a distinct set of teeth and feed on fish, squid and even larger mammals, such as seals. These whales use sound waves in echolocation to detect objects in the water. These sound waves act as a sonar and bounce off objects, returning to the whale in the form of an echo. This helps the whales determine the size, shape, speed, distance and direction of the object. Toothed whales differ from baleen whales in that they have only one blowhole instead of two and they include Orcas and Sperm whales.
Communication
Whales use sounds and body language to communicate with one another. Communication occurs through low frequency moans, grunts and thumps, as well as high frequency chirps and whistles. Whales may use use a form of song to communicate through the water, which often sounds very high-pitched to the human ear. Baleen whales have vocal cords that allow them to produce the loudest sounds on earth that travel for miles underwater. Whales also communicate by means of gestures and body language, and whale noises such as forceful spouts or the slapping of pectoral flippers may signal aggravation, indicate arousal, excitement or aggression.
Dolphins and Porpoises
Dolphins and porpoises are small whales and are both included in the group of whales known as toothed whales. Dolphin teeth are cone-shaped, and the top and bottom teeth interlock. They have a melon-shaped head with a beak. Most species of dolphins are social and congregate in large numbers feeding on fish, squid and other marine animals. Porpoises have blunt heads, small spade-shaped and do not have the beak and foreheads that dolphins have. They are also considered shy and retiring in comparison to dolphins and usually avoid contact with people.