Thanks to a new highway in Southern California, science now knows about several new species of ancient whale.
A project meant to widen a highway running through Laguna Canyon revealed fossils belonging to early previously-unknown toothed baleen whales. The findings were released earlier this month at the Advancing Science, Serving Society (ASSS) Annual Meeting. Paleontologist Meredith Rivin of the John D. Cooper Archaeological and Paleontological Center in Fullerton, California discussed the findings at the conference.
“In California, you need a paleontologist and an archaeologist on-site,” Rivin said during the meeting. State laws require public work projects like building freeways to include specialists that work alongside crews, ensuring that the construction doesn’t disturb or destroy fossils or anthropological artifacts.
Occasionally, like in this case, the law has resulted in exciting new discoveries.
The Laguna Canyon area was excavated from 2000 to 2005. Rivin was elated by the treasure trove of ancient marine life the construction revealed—fossils of hundreds of extinct marine mammals, most of which lived between 17 and 19 million years ago, were deposited in the canyon. Thirty cetacean (whale) skulls were found, including four new species of toothed baleen whale, a type paleontologists originally thought went extinct 5 million years prior to when these whales swam around California.
Excavating the new whale skeletons was no easy task for paleontologists and their crews.
"This particular specimen took about four months to uncover," Rivin said at the conference while holding a fossilized whale jaw of one of the new species. "We have about 40 volunteers who help with the process of flaking away the rocks but I haven't let them touch my whales yet."
"The whole process is very difficult," she added.
Rivin is intrigued by the fact that these whales filled a niche in the ocean ecosystem currently occupied by pinnipeds—seals and sea lions.
"Pinnipeds started showing up about this time, at least in northern California," she said. "But we have several hundred marine fossils from the Orange County site and not one pinniped fossil is there."
Current baleen whales, like blue whales (Balaenoptera musculus) and humpback whales (Megaptera novaeangliae), use blades of a fingernail-like substance to strain the ocean water for krill and other food. Their ancient relatives (though not direct ancestors), however, had teeth, teeth they used to eat animals like sharks for food.
"The more we learn about the past ocean," Rivin concluded, "the more we can learn about the future ocean."