Which water species is very close to Human beings?

Compared to other water animals, dolphins are believed to be very intelligent and very close to human beings. Dolphins are carnivores. The Killer Whale  is actually a type of dolphin. Bottlenose dolphins are the most common and well known type of dolphin. Female dolphins are called cows, males are called bulls and young dolphins are called calves.  Dolphins often display a playful attitude which makes them popular in human culture. They can be seen jumping out of the water, riding waves, play fighting, occasionally interacting with humans swimming in the water and also love to swim in front of the moving boats or ships. Dolphin is a mammal so it has to come on the surface of water to breath it use a blowhole on top of their heads to breathe. Dolphins have excellent eyesight and hearing as well as the ability to use echolocation for finding the exact location of objects. Dolphins communicate with each other by clicking, whistling and other sounds. Some dolphin species face the threat of extinction, often directly as a result of human behavior. Some fishing methods, such as the use of nets, kill a large number of dolphins every year.