Because they believe that mammals evolved from land-based creatures. When scientists studied the whales they noticed that whales share a lot of bodily functions with land living mammals despite their fishy apperance. The most obvious one is that they need to breath air, fish on the other side can breath water. Whales are warmblooded, fish are coldblooded. Whales get pregnant and have a womb where the fetus grow until it is born, fish on the other hand lay eggs which develop outside the mothers body. A whales skeleton also has several details in common with land based mammals (see http://en.wikipedia.org/wiki/Evolution_of_Cetaceans). In more recent years, scientists have compared the DNA of whales with land based mammals and found that they have a lot in common, and thus must be closely related.
Yes Whales are warm blooded which makes them a mammal
No. Whales are mamals and fish are fish (ichthyoids) -- these two kinds of animals cannot breed.
there not at TYPE of fish they are a GROUP of fish called MAMALS
whales are mamals, the question is not specific enough to provide a more detailed answer, sorry
Cetology is the branch of marine science associated with the study of cetaceans, which is the order that contains whales, dolphins, and porpoises. Logically, a scientist who studies whales is therefore a cetologist.
they evolve threw a PERIOD of time
That they evolved from land animals.
it is sewead and little tiny planktons and whales and dolphins are the most healthy mamals in the world and if you need more answer call junbug360
No dolphins had a different evolution from whales. Whales evolved from a footed creature similar to a hippo (no, seriously) and dolphins evolved from a footed creature a lot smaller.
yes they evolved from the trilobites
Mainly sea birds, Penguins, Albatross, Skuas, Shearwaters, Petrels and Terns, Seals and Whales. There are no native mamals
I'd imagine, it looks a bit like a whale. LOL