Saturday Stan and I were awed by an encounter we had with a whale in Bull Arm. It was the subject of 2 previous posts by both Stan and myself. I have another reason, other than its sheer majestic size, to be awed by the whale. Allow me to explain. We'll have to go to paleontology class for a short lesson. The next time you see a whale, maybe you see it also in a different light. Lets go.
This is an artists rendition of "Pakicetus" the earliest known whale ancestor. The skeleton was found in 1983 in Pakistan.
Pakicetus was about the size of a large wolf and lived on the edge of the Tethys Sea some 53,00,000 years ago. Its believed that Pakicetus may have exploited food in the margins of the sea where food was scarce on land. Over millions of years it progressively spend more time in the sea which precipitated the evolutionary changes we see today. As it ventured into deeper water where existing large predators roamed, evolution responded by increasing its size.
Three features of the skeleton lead scientists to conclude it was the ancient ancestor of the modern whale:
- position of the ear bones in the skull;
- folding in a bone of the middle ear; and
- arrangement of cusps on certain molar teeth.
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