Road Work Unearths a Tip of the Ice Age

In one of the most extensive such finds in western San Diego County, paleontologists have excavated remains of an Ice Age mammal while looking for fossils unearthed by bulldozers at the California 54 construction project in South Bay.

A crew from the San Diego Natural History Museum, which is under contract with Caltrans to look for and salvage fossil remains, is busy removing partial remains of a mastodon, an “evolutionary cousin” to the modern elephant, as well as vertebrae, ribs and front and hind limbs of a fossil horse.

They have also found the jaw and limb bones of a fossil gopher, limb bones and a fragment from the lower jaw of a fossil camel, and the vertebrae of what paleontologists think is a fossil bison.

Tom Demere, the Natural History Museum’s curator of paleontology, said the exact ages of the fossils are unclear, but the remains are believed to be from the latter portion of the Pleistocene epoch, which makes them between 10,000 and 120,000 years old.

The find marks the third time in little more than a year that a major paleontological discovery has been made as part of a state highway construction project in the county. In April, 1991, one of the richest fossil discoveries in Southern California was uncovered on a project to widen California 78. Animal remains were estimated to be at least 43 million years old.

And last December paleontologists found the 47-million-year-old fossils of ancient mammal species during Caltrans’ work on California 52.

Caltrans officials said Tuesday that they were working with the museum to excavate the area before construction continues. Work on widening California 54 in areas not affected by the excavation is expected to remain on schedule. The $12-million project, which should be finished within 18 months, will widen the highway to a six-lane freeway from Interstate 805 to about one mile east of Reo Drive.