A fossilised tooth belonging to an extinct Pacific mastodon was found in a creek in California`s San Mateo County.

Geomorphologist Brigid Lynch spotted the nine-inch tooth while working on a habitat restoration project for the threatened California red-legged frog.

Found partly underwater, the tooth is in excellent condition, with its crown and root intact. Donated to Stanford University`s Doerr School of Sustainability, it will be studied to determine its age. A 3D copy will be made for public education at the Midpeninsula Regional0pen Space District.

Mastodons were elephant-like animals that lived in North America until about 10,000 to 12,000 years ago.•