Scientists hope ancient Tomales Bay mammoth molar holds clues to prehistoric environment
TOMALES BAY — The color caught her eye first — pale, like bleached driftwood, against the darker rocks on the beach below the tideline. Sarah Warnock, a biologist, recognized the texture of fossilized bone when she bent to touch it.
What intrigued her was a slender, hand-shaped form poking its joined “fingers” through the stones and seaweed, as if in gesture — “Hey, there’s more here!” she said, recounting the moment.
Several calls and emails later, and Warnock had confirmed her hunch that an ancient relic had been uncovered on these shores. What she spotted on the beach that late August day was the fragile, fossilized pieces of a mammoth molar from prehistoric times.
James Allen, a licensed geologist and paleontologist who helped to unearth the Ice Age fossil, says the exciting find represents more than just “a cool mammoth tooth.” It could help him and others piece together more about the periods of warming that punctuated the long reign of our glaciated past.
It also could shed light on the history of the landscape that gave birth to Tomales Bay, a long, narrow saltwater inlet bisected by the San Andreas Fault. The bay floor there now was once part of a valley miles inland from the ocean.
“Finds like this are the bedrock of science,” said Robert Davies, a geology professor at Merced College who will be collaborating on the study of the Tomales Bay fossil. “It’s just interesting to learn about the past life and geologic story — about the ‘fossil zoo’ that we all live above. But more than that, scientifically, finds like this are important because fossils can help us determine the environments that were present when the animal was alive.”
Mammoths are among the most iconic creatures of the Last Ice Age, existing alongside sabertooth cats, giant horses, mastodons, giant ground sloths and other animals during a frozen period that dates back roughly 2.6 million years and lasted until just 11,700 years ago.
Columbian mammoths, the most common type in North America, are believed to have died out around 10,000 to 13,000 years before recorded history.
Locally, the ancestors of elephants are thought to have been among numerous long-extinct beasts who roamed broad coastal prairies that extended out beyond the Farallon Islands, now 27 miles offshore.
This theory of a “California Serengeti,” as posited by Breck Parkman, a Sonoma County resident and California State Parks senior archaeologist, is supported by numerous mammoth remains already discovered at various places around the county. They include sites in Santa Rosa, Glen Ellen, Valley Ford, Graton, and on the Estero de San Antonio near Bodega Bay, as well as in Bodega Bay itself, where a mammoth tusk and lower jaw with an attached tooth were found near Bodega Head in 1972.
Each one, said Parkman, “is another clue to the puzzle,” even though thousands remain undiscovered.
Warnock discovered the new specimen while walking on the rocky beach at the Audubon Canyon Ranch’s Cypress Grove Preserve near Marshall, where she resides with her husband, Nils, director of conservation science at the Cypress Grove Research Center.
It was upside down in a thick layer of clay beneath the rocky crust of the beach in an area covered by water at high tide. Its multi-pronged roots apparently had been exposed by the waves in recent months.