Dwarf Baleen Whale Survived into Ice Age

On carefully analyzing a fossil of the dwarf baleen whale from Northern California, researchers at the New Zealand's University of Otago reveal that this animal species survived for a longer period of time than what was previously thought.

The study, which was led by Robert Boessenecker, PhD, Otago Department of Geology, found that the 4-5 meter long fossil of Herpetocetus that is considered to be the last survivor of cetotheres, the primitive baleen whale family, could be as young as 700,000 years old.

Previously, the youngest known fossil of this whale was from the pre-Ice Age Pliocene epoch, which was some 3 million years old. Such types of baleen whales were common some 10-15 million years ago.

"That this whale survived the great climatic and ecological upheavals of the Ice Age and almost into the modern era is very surprising as nearly all fossil marine mammals found after the end of the Pliocene appear identical to modern species. Other baleen whales underwent extreme body size increases in response to the new environment, but this dwarf whale must have still had a niche to inhabit which has only recently disappeared," Boessenecker was quoted as saying in a news release.

The finding hints that the emergence of the modern marine mammals during the Ice Age occurred more gradually than what was earlier thought. It indirectly supports the hypothesis about the modern pygmy right whale. Boessenecker's colleagues professor Ewan Fordyce and Dr. Felix Marx assume that the southern ocean whale is not the right whale, but a member of cetothere family and the closest member of the Herpetocetus.

If the hypothesis is true, then the new finding suggests that close relatives of the pygmy whale survived till modern times, that too within the Northern Hemisphere.

The study appears in the journal Naturwissenschaften.