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Geological Museum to Offer Rare Look at Early County

May 06, 1987|JIM WALTERS | Walters is a Times copy editor.

Sometimes Steve Conkling's job is the pits. That's when he likes it best.

Under a hot sun, he kneels in a three-foot hollow in the side of a slope, carefully picking through the dirt for fossilized mice teeth and bird bones. "You don't even have to look too hard to find them out here," he said. "This area is loaded with fossils."

Conkling is the Orange County Environmental Management Agency's first paleontologist, hired last August to help excavate, study and protect a trove of fossils at Ralph B. Clark Regional Park in northern Buena Park. He and his staff of two part-timers have been sorting through a 25-year backlog of items. Among them have been some surprises: a diving goose, a miniature horse and rare camel bones.

"Animals don't go to the cemetery," said Conkling, 25, of Brea. "They just die out in the hills and flatlands. Then the rains wash their carcasses into streams and lakes." It is in this prehistoric potter's field where thousands of those bones collected and were buried over time.

Marine fossils indicate that what is today Clark Park was part of an ocean 125,000 years ago. An upheaval about 75,000 years ago created the Coyote Hills and a stream that meandered to the sea. About 15,000 years ago, the stream straightened, formed an oxow lake that slowly became a marsh, then an oak woodland.

Fossils of at least 30 animal species have been found from the cliffs north of Rosecrans Avenue to the slopes on the east side of the park. They include mammoths, elephants, great sloths, black bears, ring-tailed bobcats, rodents, voles (small rodents with stout bodies and short tails) and at least 35 species of birds, Conkling said. Plant fossils also have been uncovered.

Those clues to the past will be displayed at the $632,000 Interpretive Center, a park museum that Conkling will oversee when it opens within nine months. Hal Krizan, director of the county's parks and recreation division, said Conkling will be offering his services to other rangers and organizations when finds are made elsewhere in the county, but his primary duties will be at Clark Park.

Conkling's $24,000-a-year post as county paleontologist is unique, according to the Southern California Assn. of County Governments.

The center, Conkling said, will become the fourth on-site fossil museum in the Western Hemisphere. It will join two such facilities in Canada and the George C. Page Museum at the La Brea Tar Pits in Los Angeles, he said.

La Brea has an impressive collection of predatory animals, which were mired in the tar with their prey, Conkling said, but the Clark Park dig contains "a more complete picture of the area thanks to all the carcasses that washed down into the old lake from a wide area over the centuries."

Several bones from the old freshwater lake bed belonged to camels that roamed Orange County about 15,000 years ago.

"The Palaeolama mirifica has only been found in one other place in the United States: Florida in the early '70s," Conkling said. "We believe that camels developed about 35 million years ago in what is now South Dakota and some of them moved into South America--where they have been found in Ecuador and Bolivia--and others to Asia across the Bering Strait. Those camels failed to survive in North America, evolved into those we have today in Asia and underwent evolutionary changes in South America, becoming a llama-like creature."

Climate and continental drift isolate species and are partly responsible for the evolution of new ones, Conkling said. Over time, one species may have evolved into several in an isolated area, with new animals adapting themselves to the land's changing resources. Some developed teeth to cut the tops of the grasses as they ate, while the mouths of others adapted to chew the stalks left behind.

Eons ago, when South America was linked to Australia and Antarctica, he said, marsupials diversified.

"At one time there were even saber-toothed animals with pouches," he said, "but (after those continents separated) the camels were better at eating grasses than their marsupial counterparts, driving them to extinction in South America.

"When the land bridge (Panama) appeared between North and South America about 10 million years ago, we got armadillos and possums from the south and they got camels, tapers and saber-toothed cats from the north. This interchange continued until about 6,000 years ago and then stopped due to climate changes. That's when the llama developed."

Palaeolama bones found in Florida are about 250,000 years old, he said, a great deal older than the specimens found at Clark Park. How the camels came to the area is uncertain.

"We don't have a clear picture of it all yet. It just may be that the Palaeolama split into two isolated groups as it traveled north, some going to Florida, others here," Conkling said.

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