why would a dolphin breathe air when it lives in water?

Answer 1

They are mammals, so they have lungs and can not absorb enough oxygen to survive. Dolphins evolve from a land animal that return to the sea. There is a belief that dolphins can absorb oxygen from the sea, but because they are warm blooded, they require large amount of oxygen, which sea water can't provide. Many warm blooded animals evolve to become sea creature, because of the abundents of food. Warm blooded animals are smarter and in some ways faster than cold water animals, gave an incentive for some species to become sea creatures. Warm blooded animals though require large quantity of oxygen to run its supercharged matabolism, which why fish never evolve into being warm blooded.

Answer 2

It's thought that dolphins, as well as sea Lions, seals, and other aquatic mammals, evolved from land walking mammals which lived near the shoreline and spent more and more time near the water, eventually returning to it.

In fact they recently found a dolphin with perfectly formed leg remenants. Snakes also have these as they evolved from legged creatures.

Answer 3

The dolphins sleep in 2 procedures: horizontal or vertical in a good number of cases with yet another dolphin beside them,answering the information of your question the dolphins spend 33.4% of the day slumbering so even as storms and waves comes they don't drown beacause they have the administration of its espiraculus, espiraculus is a spread of skin desing to open and close lower than the administration of the dolphin. A dolphin can breathe 8 to 12 cases in step with minute even as that is swiming and lively and three to 7 cases in step with minute even as they sleep. opposite direction they sleep is by been contained in the exterior and in a good number of cases that position may be actual confuse with a timber log stick. honestly they don't die by the reason behind drawning, yet they could die even as they're been stalked by different animal and they wade through a panic attack that cause them to swim extra contained in the bottom making them die, also even as they stay traped in a fishing internet the die by sofocation

Answer 4

because mammels need air. dolphins are mammels...so are whales such as the blue whale, killer whale, sperm whale...etc.

supposidy during evolution some mammels decided to go back into the water and thus after millions of years they started evolving into marine mammels. kind of like seals...but MUCH MORE dependend on water since they physically evolved differently from a seals body, and life style. thats why if you look at a whales bones...they have hind legs!

http://www.livescience.com/animalworld/top10_vestigial_organs-9.html

Answer 5

Because it is a mamal not a fish and thats one of the classifications of BEING a mammal ( breathing air)

Answer 6

because God made them that way. I dont see them complaining. It doesnt sound too strange that a dolphin living in water needs air occasionally and us living on land need to drink water sometimes.

Answer 7

Boy, I really hope you are like 5 yrs. old or something. It's a mammal hoss. They don't have gills.

Answer 8

because it once was a land mammal and it evolved to live in the ocean.

Answer 9

Because its an aquatic mammal

Answer 10

It is a mammal. So are whales.