In 2012, a construction crew digging more than 110 feet below ground at the Salesforce Transit Center construction site at 1st and Mission Streets made a rare discovery: the fossil of a woolly mammoth tooth. The tooth was found in remarkable condition, the enamel still intact.
How did a woolly mammoth fossil end up in an urban center like San Francisco’s East Cut? The answer lies 11,700 years ago, at the end of the last great ice age, when San Francisco’s coastline extended 28 miles west beyond the Farallon mountains, whose peaks now make up the Farallon Islands.
At the time, the San Francisco Bay Area was a grassy valley that closely resembled the Serengeti of east Africa. Large land mammals such as saber-toothed cats, mastodons, elk and bison migrated from Asia over a land bridge to roam prehistoric San Francisco. The largest of these land mammals was the woolly mammoth.
Standing 13 feet tall and weighing as much as 24,000 pounds, mammoths were almost twice as large as a modern-day African elephant. Their curved tusks could be up to 16 feet long.
Upon the fossil’s excavation, the Transbay Joint Powers Authority (the agency building Salesforce Transit Center) gifted the discovery to the California Academy of Sciences, where it is currently on display. Where woolly mammoths once roamed after long overland journeys, buses and trains will bring humans to the same destination in the East Cut.