why whales are called mammals ?

Answer 1

by the definition of mammals:

they have mammary glands

Answer 2

Be careful here - there were a lot of bad answers - many people seemed to say because it had the characteristics of a mammal as if it was a resemblance. They're called mammals because, not to put too fine a point on it - THEY ARE MAMMALS.

Mammals evolved on land though, don't they? Well yes, but think about seals, sea-lions, otters - evolution is an unending process - these other animals might become might adapted to life in the ocean in another few million years. Life came out of the ocean but if there's food, an opportunity to survive, life can go back.

Cetaceans just moved to the sea much earlier that those other groups. I'd recommend you look up dolphin or whale evolution to take a look at some good websites or look for some important transitional species: Pakicetis, Ambulocetis, Basilosaurus (-saurus because when the fossil was first discovered they thought it was a reptile) what does it really mean to say something is a mammal?

Well Mammalia isn't just a grouping of resemblances. Its a family (not Family as in taxonomic naming systems I mean it quite literally) there was a first mammal about 200 million years ago - and all its descendents are mammals, able to trace their roots right back to it. They have become the most successful of groups - adapting to fill all niches on the lands and in the oceans.

Kind regards.

Answer 3

the main reason whales are mammals is the double lining of the placenta. they do not have hair as most other mammals do. They are tetra pods, which means in evolution that they were once land animals, and for some reason they walked back into the water. they have lungs, although reptiles and birds do, so thats not the main reason. there fins like dolphins are actually hand bones, called filanges.
and remember, not all mammals have hair, or lay eggs. as the whale and dolphin don't have hair and the duckbilled playtipus lays eggs, yet it's a mammal.

Answer 4

They are classified as mammals because they fit several cretia:
Do they breathe air?
Are they warm blooded?
Do they have hair? YES! whales usaully have eyelashes and hairs around the chin.
Give birth to live young? yes
Suckle or nurse?

Answer 5

Their distant relatives were land dwellers. About 50 million years ago or so they came back to the ocean and stayed there.
They have mammary glands
They must come to the surface to breathe oxygen (rather than separating the oxygen from the water w/ gins).
Has a four chambered heart.
They are endothermic (warm-blooded) (this does not count as a defining point because birds are endothermic as well)
They give birth to live young (this not a defining point because one of the sharks gives birth to live young)

Dolphins are a sub-division of whales... just to let you know

Answer 6

They have the characteristics of a mammal.
They give birth to their young alive.
They breathe through lungs.
They are warm blooded.

Answer 7

Any animal who nurses it's young are called mammals,even whales and dolphins

Answer 8

because they suckle their young ,on milk
this is what mammals means
Mammals are land animals that breathe air
and whales have lungs they bread air like Dolhins,seals ,Orcas,etc

Answer 9

1. They breathe air
2. They give birth to young
3. They lactate (which makes them mammals)
4. They suckle their yong (which makes them mammals)

Answer 10

Thats A Good Question. They breathe with there lungs unlike fish. They give birth to live young. Other reasons check ths website.

Answer 11

this is because they have the same characteristics as mammals

- they give birth to live babies
- they produce milk for their young
- warm-blooded