Geologist Discovers Exceptionally Preserved Pacific Mastodon Molar in California Creek
While conducting a survey of a creek in San Mateo County, California, for a conservation initiative focused on the California red-legged frog, geomorphologist Brigid Lynch from Balance Hydrologics stumbled upon a significant object. A reverse image search indicated it might be a molar from an Ice Age mastodon, a finding later validated by paleontologist Wayne Thompson. This fossil, an upper left molar from an adult Mammut pacificus, is the most remarkable specimen Thompson has encountered. Pacific mastodons roamed California between 2.5 million and 11,700 years ago, sharing their habitat with various species. The molar was placed in creek water by Midpen staff and subsequently donated to Stanford University’s Doerr School of Sustainability for analysis and replica production. In 2023, Jennifer Schuh discovered another mastodon tooth on a California beach.
Key facts
- Brigid Lynch, a geomorphologist at Balance Hydrologics, discovered the fossil in a creek in San Mateo County, California.
- The fossil was identified as an upper left molar of an adult Pacific mastodon (Mammut pacificus).
- Wayne Thompson, a paleontologist and CEO of Pacific Paleontology, confirmed the identification.
- The Midpeninsula Regional Open Space (Midpen) manages 70,000 acres of public open space in the greater Santa Cruz Mountains.
- Pacific mastodons lived from 2.5 million to approximately 11,700 years ago in what is now California, Oregon, the northern Rocky Mountain region, and parts of Mexico.
- The tooth was placed in a bucket of creek water after retrieval to prevent decay.
- The fossil was donated to Stanford University’s Doerr School of Sustainability for age determination and replica creation.
- In 2023, another mastodon tooth was found at Rio Del Mar State Beach by tourist Jennifer Schuh and later donated to the Santa Cruz Museum of Natural History.
Entities
Artists
- Brigid Lynch
- Wayne Thompson
- Ron Tykoski
- Jennifer Schuh
- Jim Smith
- Sooji Nam
- Jamie Stengle
- Margherita Bassi
Institutions
- Balance Hydrologics
- Pacific Paleontology
- Midpeninsula Regional Open Space
- Stanford University’s Doerr School of Sustainability
- Perot Museum of Nature and Science
- Santa Cruz Museum of Natural History
- New York Times
- CBS News Bay Area
- Associated Press
- Smithsonian Magazine
Locations
- San Mateo County
- California
- United States
- Santa Cruz Mountains
- Oregon
- Rocky Mountain region
- Mexico
- Dallas
- Texas
- Rio Del Mar State Beach