And in case you missed this, Japanese fishermen caught a dolphin with a vestigial pair of limbs. As the article points out:
Fossil remains show dolphins and whales were four-footed land animals about 50 million years ago and share common ancestors with hippopotamuses and deer. Scientists believe they later transitioned to an aquatic lifestyle.
Much like the Tiktaalik fossil that was found in the arctic a few months back, this shows evidence of an evolutionary lineage. Cool!!