Whale Evolution: by Nature Video

Like she said they have thick bones similar to the hippopotamus to reduce their buoyancy, so the animal effectively sinks and can walk on a river bottom.

Samopurple, do you mean the bones worked as "cement galoshes"? Then the animal would drown. Hippopotamus does not walk on river beds; it is a good swimmer. It walks on land, and that is why he needs thick bones - to support its huge mass. Elephant has thick leg bones, and it does not live in water. My point is: thick fossil bones do not mean it lived in water. To make that claim is like shooting an arrow at a wall, paint a bulls eye around it, and claim perfect shot. It is not science.

Im sure more bone adds to bouancy

postme12, bones sink; look at soup. My point is: science must be based on knowledge, not wishful thinking. Knowledge shows that land animals have thick bones; aquatic animals, including whales, have thin, soft, spongy bones. For an aquatic animal to develop thick bones would be a miracle, not evolution.

Aeg1000, i would be careful when using the word 'miracle' when people are talking about science seriously. I wasn't stating that the bones float i was merely proposing that bone helps bouancy, well better than fat or blubber would. I could be wrong however and i do like it when im wrong so i learn something. I think you need to look at a the evolution of the whale more closley to tell you that the animals physiology evoloved to it's best means.

Another factor you don't mention is the higher pressure under water. Water creatures need thick bones in order for them to handle the higher pressure. A human swimmer don't swim very deep, therefore it don't need thick bones. Whales on the other hand do need it.