Are whales descended from land dwelling mammals?

Answer 1

Yes, perhaps they once did.

Evidence shows that whales have a pelvic bone, which is not used for anything else but having legs and walking.

Besides this assumption, there is little to no proof. They legs disappear but this all happened when dinosaurs lived on earth.

Answer 2

Mammals originated on land, but by this point, land was no longer the easy, open space that it was when reptiles first evolved on it. There was competition with other mammals, and with birds and reptiles. It made sense for mammals to return to water, where there were fewer large animals. The ancestors of whales were land mammals. Specifically, they were hoofed mammals. They may have been a group of hoofed mammals called pakicetids, which lived about 53 mya (miilion years ago), or they may have belonged to the genus Indohyus, which lived about 48 mya. One of these probably evolved into the genus Ambulocetus, an amphibious mammal that lived at about the same time as Indohyus. Ambulocetus had webbed feet, an aerodynamic body shape, and no external ears, meaning that it had adapted to water. The family Protocetidae, which lived from about 49 mya to about 37 mya, may have evolved from Ambulocetus. They had limbs with which they could support their body on land, and they gave birth head first, as do land mammals. One genus is known to have had hooves. However, they further adapted to the water in that their nasal openings moved up on the top of their snouts, and their sacra (fused bones connecting the spinal column to the pelvis) divided to some extent. Two genera called Basilosaurus and Dorudon lived just after the protocetids. They probably did not move on land, but probably did not dive deep into the ocean either. They look more like modern whales. Their heads are longer, with no neck, their limbs are shorter, their sacra have fully divided, and they probably had caudal fins, as do modern whales. Those two genera probably evolved into modern whales. Some features of modern whales, such as echolocation and baleen (in baleen whales), probably did not appear until more recently.

Answer 3

Im not that sure about my answer but, I don't think they used to be land animals. If your not sure i suggest you can look it up on the internet or ask a person who works with whales like at the zoo or aquarium :)

Hope this helped =)

Answer 4

Whales are mammals that are adapted to survive in the ocean. If a whale comes to land, it will eventually die.

Answer 5

it was believed that whales were land animals because i said so

Answer 6

nooo , it swims in the big blue ocean :) ( and lives there too...)

Answer 7

A whale is a sea mammal