Unnamed extinct gray whale from Pliocene San Diego Formation of San Diego, California

[DD1991]

Took this photo of an unnamed eschrichtiid from the Pliocene San Diego Formation of San Diego County in March 2019. Until the 2000s, the fossil record of gray whales was confined to the Pleistocene, but thanks to the work of Michelangelo Bisconti, it is apparent that gray whales emerged about the same time as the oldest rorquals (Eschrichtioides was long considered a balaenopterid, but eventually recognized as a gray whale relative).