“Oh my God,” Richard Cerutti said to himself. He bent down to pick up a sharp, splintered bone fragment. Its thickness and weight told him that it belonged to an animal, a very big animal. His mind started to race.
He was standing at the foot of a slope being groomed by Caltrans for a road-widening project through the Sweetwater Valley near National City.
Earthmoving equipment had already uncovered other fossils from elsewhere on the site, mostly rodents, birds and lizards. But this bone was from no ordinary animal. The operator wanted to keep digging, but Cerutti raised a fist to stop him. He felt a tightening knot of anger.
The contractors had worked over the weekend without contacting him, and he could see the damage they had done. He sprinted up the slope to a construction trailer and picked up a telephone.
“Tom,” he said. “I think I have a mammoth out here on State Route 54. Can you send some help?”
Back on site, Cerutti persuaded the operator to move the excavator out of the way. He grabbed a few tools from his truck: an ice pick, an old paintbrush and his prized table knife lifted from a Black Angus restaurant.
Kneeling among broken bones, he dusted away loose soil and began probing the sediment. His adrenaline surged as the outline of a tusk slowly emerged. Inches from the tusk, he found a stone. One edge was smooth, almost rounded. The other was sharp as a razor.
Cerutti had made stone tools before, and he knew how rocks fracture and break. Nothing about the shape of this rock was natural; something had struck and broken it with great force.
What the hell had he stumbled upon?
Cerutti hardly suspected that on this day 25 years ago, Nov. 16, 1992, he was standing atop a discovery that could rewrite the opening chapter in the history of the New World.
Now retired, Richard…