Why can t whales just swim under water all the time?

Answer 1

The reason whales die rather quickly when they're stranded on a beach is two things. First, their bones are lightweight and porous, much lighter than the bones of land animals. this is because, in the water, the bones don't have to provide the kind of support that ours do on land, so they've evolved more as places for muscles to attach to than for actual support. On land (away from the buoyant water where gravity isn't a big factor), the whale literally crushes itself under its own weight. Second, they overheat. Most whales are designed to live in cold water, which takes heat out of a body some 20 times faster than air does. Their fat (blubber) insulates them very well in the water. On land, however, they dont have the cooling of the water, and the blubber makes them overheat. Dead whales literally cook inside, since after death the thermoregulatory mechanisms that normally cool the animal are shut down, and decomposition sets in, inside what is essentially a big pressure cooker (the body).

Answer 2

Way back in ancient history, they did, but not anymore.

There have been skeletal remains of whales with rudimentary legs found in the Egyptian desert. However, whales have lived in oceans for a very long time now.

Answer 3

All whales can breathe on land, but they can't live very long on land, because they cannot move around and feed out of the water, and they will dry out and their body temperature will go out of control if they are out of the water for any significant length of time.

Answer 4

The ability to live on land is not a taxonomical requirement for mammals. Whales have all of the characteristics that define an animal as a mammal, and so they are classified as mammals. Taxonomy is artificial, so if you wanted to make the ability on land a taxonomical requirement for mammals, then whales are not mammals, but this would only be for your personal taxonomy. Whales cannot live on land because their ancestors, which lived on land, "realized" that the oceans were an open ecosystem into which they could enter and dominate, and so, over millions of years, they adapted to the point that they were able to spend all of their lives in water. However, many of the adaptations that allowed them to spend all of their lives in water also prevented them from, hypothetically, living on land.

Answer 5

Because they are mammals with lungs and must surface to breathe air. They don't have gills for breathing like fish.

Answer 6

They are mammals, not fish.

Answer 7

no