Amazing but true 17

The whale is by far the largest of the wading birds. Environmental changes over millions of years have resulted in evolutional repurposing of their limbs. Their wings, rarely used even in their prime, have become like flippers, propelling them gracefully through the depths, while their long slender legs remain - just very, very tiny.

Sometimes likened to fish and often laughably referred to as mammals, whales, and in particular the blue whale, distant cousin of the blue tit, are the true kings of the bird kingdom. 

Even larger, some say, than the elephant.