In a previous post I thought I had referred to discovery of a tooth on a baleen whale's nose, but the posts on whales of last August and September did not have it. So, at the risk of being repetitious, a whale that had washed up on a Tasmanian beach about six months before the pictures below were taken, in 1956 or 1957, was badly decomposed in the part exposed to the air. The part deep in the salt-water laden sand still had fresh-looking red whale meat. It had been identified as a Pygmy Right Whale. We were there to get as much of the skeleton for the University of Tasmania's collections as my advisor (Dr. Guiler from the Zoology Department), another faculty member from the university, and myself could.
The ribs in the foreground were pulled from part of the carcass after the layer of skin or blubber (the brown layer that also had not decomposed) was moved. As is evident the very gently sloping beach was perhaps a factor in the whale beaching itself. It probably lacked a reflective surface to effectively return signals to the whale telling of the end of the ocean. The skull is not obvious in the photo, but in the photo below you can see the part of the jaw with the tooth at the end is already quite weathered by exposure.
The tooth is of interest for several reasons. It is certainly an indication the whale is derived from a toothed ancestor. Its persistence suggests it has had some survival value in its ancestors and probable continuing value. It may be of value in ramming an opponent. The saga a few years ago of a whale in danger of being trapped in the Arctic Ocean as early winter ice was forming made me think it might be of use in fracturing the ice to enable breathing to support it for a longer under ice trip to open water or a new thin area to break. It might suggest a relationship with narwhals and their long tusk.
If you read my posts on creativity you should realize we should at least consider the possibility that the tooth is a new development rather than a holdover from ancestors with tooth filled mouths. I think the fossil record is adequate to dismiss such an idea and go on to other things. One of those things might be the observation that marine mammals are thought to be the only placental mammals native to Australian shores and lands other than the bats prior to the arrival of humans. So I will end with an example of a bat from Tasmania, circa 1957.
Joseph G. Engemann June 2, 2014
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