Ice Age Mastodon Tooth Discovered in California

A recent survey of a California creek led to an unexpected find for a scientist: a tooth from an ancient Ice Age creature.

This tooth, identified as belonging to a Pacific mastodon, was located in a preserve managed by the Midpeninsula Regional Open Space District in San Mateo County.

These mastodons were large, elephant-like herbivores that disappeared around 11,700 years ago, towards the close of the last Ice Age.

Brigid Lynch, a geomorphologist with Balance Hydrologics, made the discovery while assessing the creek to enhance the habitat for the endangered California red-legged frog. She expressed her surprise in a statement, saying that, although she has seen various things in the field, finding a mastodon tooth was particularly thrilling.

At first glance, Lynch mistook the molar for an oddly-shaped rock, but its unusual structure soon became apparent. According to Wayne Thompson, CEO of Pacific Paleontology, the tooth is in “immaculate condition.”

He noted that the tooth likely dates between 50,000 and 100,000 years old based on its location, contrary to some reports suggesting it was only 10,000 years old. “There’s a lot of misinformation about its age,” Thompson clarified. “We can confidently say it’s much older than that, possibly around 50 to 100,000 years.”

Thompson elaborated on the tooth’s condition, remarking that it hadn’t moved much after the mastodon died, indicating that it hadn’t been tumbled around in the stream. “The roots of mastodon teeth are quite fragile, but this one still has the majority of its roots intact,” he explained.

He speculated that the skull and other bones of the animal could still be buried at the site where the tooth was found. “It probably just came out of the skull,” Thompson suggested.

Finding such a well-preserved mastodon molar is “extremely rare,” he noted, calling the discovery quite uncommon.

Looking ahead, researchers from Stanford’s Doerr School of Sustainability plan to carbon date the tooth to pinpoint its age. They also intend to create a 3-D scan of it for further study and replication.

Interestingly, mastodons preferred browsing on leaves—such as those from alder trees—rather than grazing on grasses like their mammoth counterparts. Thompson noted that these trees are still present along the creek where the tooth was discovered, suggesting that the environment has maintained some continuity over thousands of years.