A woman talking a weekend stroll along a California beach found the tooth of an ancient mastodon sticking out of the sand.
Jennifer Schuh found the foot-long tooth on Friday at Rio Del Mar State Beach, in Santa Cruz County.
“I was on one side of the creek and this lady was talking to me on the other side and she said what’s that at your feet,” she recalled, adding: “It looked kind of weird, like burnt almost.”
Ms Schuh wasn't sure what she had found. So she snapped some photos and posted them on Facebook, asking for help.
Wayne Thompson, palaeontology collections advisor for the Santa Cruz Museum of Natural History, took notice and said the discovery was an "extremely important find".
He urged Ms Schuh to call him about the worn molar, which belonged to an adult Pacific mastodon - an extinct elephant-like species.
However, when they went back to the beach, the tooth was gone, and a whole weekend of searching failed to uncover it.
Mr Thompson then sent out a social media request for help in finding the artifact. The plea made international headlines. On Tuesday, Jim Smith of nearby Aptos called the museum.
“I was so excited to get that call,” said Liz Broughton, the museum's visitor experience manager.
“Jim told us that he had stumbled upon it during one of his regular jogs along the beach, but wasn’t sure of what he had found until he saw a picture of the tooth on the news."
Smith donated the tooth to the museum, where it will be on display Friday through Sunday. The age of the tooth isn't clear.
A museum blog says mastodons generally roamed California from about 5 million to 10,000 years ago.
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“We can safely say this specimen would be less than 1 million years old, which is relatively ‘new’ by fossil standards," Broughton said in an email.
Broughton said it is common for winter storms to uncover fossils in the region and it may have washed down to the ocean from higher up.
It's only the third find of a locally recorded mastodon fossil. The museum also has another tooth along with a skull that was found by a teenager in 1980 in the same Aptos Creek that empties into the ocean.
Museum executive director Felicia B. Van Stolk said: "We are thrilled about this exciting discovery and the implications it holds for our understanding of ancient life in our region.”
Schuh said she is thrilled that her find could help unlock ancient secrets about the peaceful beach area, adding: "You don’t often get to touch something from history."