Bulldozer Blades Help Uncover Fossil Clues to Prehistoric San Diego

As bulldozers lumber across an open field that will soon accommodate the Chula Vista Eastlake housing development, paleontologists scramble in a small flagged-off area as they try to salvage the fossilized remains of San Diego’s former inhabitants.

The paleontologists, scavenging in the tracks of a bulldozer at the Eastlake project in April, discovered the fossilized remains of a prehistoric pig-like creature. The extinct Oreodont is traditionally found in the Midwest.

Led by Dr. Thomas Demere of San Diego’s Natural History Museum, the three scientists are working with the development company, digging for more fossil samples from what was once the prehistoric Rosarito Beach--samples that will help them understand what prehistoric San Diego was like during a sparsely researched epoch.

The collaboration between land developers and paleontologists (who dig for and study fossils) is increasingly common at construction sites in the fossil-rich Chula Vista area. The City of Chula Vista requires land developers to open their construction sites to paleontologists before they can get development permits.

According to Demere, the April discovery fills a significant knowledge gap for San Diego paleontologists, who had scant information about the area during the Miocene Epoch of roughly 16 million years ago. Earlier discoveries had provided scientists with information about the Eocene Epoch (40 million to 45 million years ago) and the marine-life fossils of the Pliocene Epoch (2 million to 3 million years ago).

In 1981, two museum paleontologist, who were hired by the Watt Industries development firm, discovered a huge whale skeleton while walking behind a bulldozer at a Chula Vista construction site.

Again, in 1983, scientists discovered evidence of an approximately 2-million-year-old prehistoric elephant at the same Chula Vista site. That discovery marked the first terrestrial fossil finding in coastal San Diego, which had been known primarily for its marine fossils.

By the time the Oreodont was discovered, the scientists had established an amiable relationship with the land developers they worked with.

When the Chula Vista City Council first passed a resolution calling for fossil research as a condition of land development approval, reaction was mixed, said Doug Reid, Chula Vista’s environment review coordinator.

“It used to be that developers would say, ‘Let’s bulldoze and to hell with science.’ Those days are over,” said Richard Daniels, a spokesman for the Eastlake development.

But developers were slow to accept the idea of scientists digging in the tracks of their bulldozers.

They initially feared that the research would slow down or postpone their projects. “Eventually they realize we just want to collect samples, and they come around,” Demere said.

“It could be a bad situation if we were pushy and the developer was pushy, but that wouldn’t do either of us any good.”

The Eastlake Oreodont fossils, like those found on earlier excavations, will become part of the permanent collection at the Natural History Museum.