The fossil, which is a nearly complete skeleton, has a mix of primitive and advanced characteristics at an earlier time period than previously thought, requiring a revision of previously accepted whale evolution theory. Specifically, this fossil is the oldest known baleen, or mysticete, whale with no teeth. Baleen whales evolved from toothed whales (similar to orcas and dolphins) and all primitive mysticetes have both teeth and baleen. Other surprising features of the new whale are that the skull is broad on top, with the nasal opening located farther forward than in modern mysticetes. These features suggest that the fossil whale was a bottom feeder, similar to living gray whales, but much smaller.
"This is a unique animal found early in the evolutionary chain. It is hard to know exactly where to place it in the evolution of whales," says Dr. Lawrence G. Barnes, Curator of Vertebrate Paleontology, at the Natural History Museum of Los Angeles County. Barnes had been working collaboratively on this particular whale fossil with Burke Museum Affiliate Curator, Jim Goedert and Burke Museum Fossil Preparator, Bruce Crowley, since 1995, when Crowley and Burke Museum staff first mounted an excavation of the fossil. It took Crowley three years to prepare and mount the skeleton for display, because it was imbedded in many pieces of concrete-like rock. "This fossil represents an unprecedented record of this animal which lived at a particularly exciting time in evolutionary terms," says Crowley.
Dr. Liz Nesbitt, Curator of Invertebrate Paleontology at the Burke Museum, comments that, "This is a previously unknown genus and species of baleen whale—a very exciting find." Crowley and Barnes are currently writing the initial research manuscript on the whale describing all it's new and unusual features. The whale will be given an official scientific name in this published description.
Goedert comments that, "This is an exciting discovery. We are finding whale fossils here in Washington state that are so different that they are tough to classify, and they complicate current definitions of some types of whales. Some of these new characteristics are significant enough that scientists may have to rethink the origins of some of today's whales."
The result of these findings? A more complex evolutionary history of whales and dolphins is emerging. The Olympic Peninsula whale fossils in particular, may possibly be the evolutionary Rosetta stone, or "missing links," in whale evolution. (Photo of whale fossil, above, by Gabe Kean.)
