From what little I have read, a whale supposedly has elongated forelimbs(flippers). It also has greatly reduced hindlimbs. It has a very large rib cage in relation to its body. The tail has no fused end vertebrae. From the drawing of the skeleton, it looks like the tail end vertebrae are missing. Since there is no soft tissue left, one cannot determine what this creature was capable of doing.
It appears to be a whale because one can see what skeletal changes need to be done to make it look like a modern whale skeleton. Not convinced it is actually a whale ...could be related...but most likely, not a whale. It is only a proto-whale because one expects evolution to have occurred later on. IMHO
They are forever searching for the ‘Missing Links’, the ‘proto-whatevers’ of evolution.
Where is the fossil of the short necked giraffe?
Where is the fossil of the flying penguin?
Where is the fossil of the snake with legs?..................