Animals such as the dolphin, the whale, the dolphin and the whale orca are part of the cetaceans. They all share a number of characteristics: they live in the marine environment, are vertebrate mammals, breathe through their lungs, are warm blooded and have a bifurcated fin at the end of their body.
During the first period of life, the offspring feed on breast milk obtained from the mammary glands and when they become adults they feed on crustaceans, molluscs, small fish and plankton. In this way, cetaceans have aspect of fish, but in reality are mammals.
The term cetacean comes from the Greek word ketus, which literally means sea monster.
From an evolutionary point of view, these animals form terrestrial, but 200 million years ago they began their adaptation to the aquatic environment. As for their habitat, they can be found in oceans, coasts and rivers, both in cold and warm waters.
The communication system of cetaceans
These aquatic mammals have an underdeveloped sense of smell and their eyes are adapted to see both in and out of water. Their hearing is extremely powerful and sophisticated as they are capable of perceiving ultrasound.
They use two types of sounds: some are intended for locating food and detecting dangers and others for communication between members of the same species. This communication system is known by the term echolocation. It consists of emitting all kinds of sounds through bursts or sound impulses. When these impulses return to the cetacean’s brain, it obtains precise information about its surroundings. Therefore, the sound echo provides detailed information about possible prey or danger.
Also, they have low frequency waves and thanks to them cetacean groups can communicate effectively.
In the case of dolphins, hunting-related echolocation has the following phases:
1) the dolphin rises to the surface of the water and opens the spiracle to allow air to enter;
2) as soon as the lungs have air, their nose swells and their phonic lips open and close to emit a vibration;
3) sound waves are formed with different frequencies;
4) these sound waves travel through the water and then repulse objects or animals;
5) the waves return to the dolphin in the form of an echo, then are perceived by the ear and finally interpreted by the brain.
Social and very smart animals
Cetaceans are able to organize and coordinate themselves for very different tasks: getting food, offering help in the face of a threat , taking care of the offspring or carrying out group displacements.
In short, they are social animals and only adult males live in isolation during very specific periods.