Upside of El Nino's Thrashing: Fossil Finds Galore
Fossil hunter David Whistler wasn't finding much at all - until an El Nino's -fattened storm struck.
El Nino has been very, very good to David Whistler.
While some in southern California still struggle with the mess wrought by the season's pounding rains, Dr. Whistler, curator of paleontology at the Los Angeles County Museum of Natural History, is reveling in its aftermath - and what's turning out to be a great year for fossil discoveries.
Shovel-and-brush toting scientists have found everything from a big camel-like creature (Gigantocamelus) to the jawbone of an ancient horse.
"We've just had an amazing amount of stuff showing up," says Whistler, who for 30 years has done his field work at Red Rock Canyon State Park, where the Sierra Nevada rise from the arid plains of the Mojave Desert.
This is one of the region's most fossil-rich areas. Yet often a few millimeters of dust obscures a big find. So scientists mostly rely on wind and rain to clear the way. But the occasional gentle shower does little to reveal treasures under the sand. It takes nature's more-forceful moments to turn back a page of the fossil record.
"Two things paleontologists wait for in southern California," Whistler says, "are El Ninos and brush fires."
About 26 million years ago during the Miocene epoch, Red Rock was a scrub forest with a climate similar to present-day central Mexico. The life that inhabited it - 87 species identified so far - was incredibly plentiful and diverse. Some species, particularly the smaller ones Whistler specializes in, such as squirrels, mice, and frogs, might be easily recognized today. Other larger animals have no living counterpart.
Scientists routinely scour this 50-square-mile fossiliferous terrain for ancient bones. Yet until they get help from nature, the progress can be slow.
When the last El Nino tore through Red Rock in 1983, for instance, it produced, among other things, the complete skull and forelimbs of a 9.75 million-year-old carnivore, a species of dog so new to science it has yet to be named.
Until last September, however, Whistler was finding less and less of interest. That changed when an El Nino-fattened storm hit the park with almost 15 inches of rain in four hours, clearing off as much as four inches from the surface - and obliterating the park headquarters in the process.
In March Whistler and some volunteers went back to Red Rock. He found the complete lower jaw of what he thinks is Dinohippus leardi, the largest fossil horse of the park's Miocene fauna.
But Whistler felt he should be finding more. On a second field trip over Memorial Day weekend, he did.
He had conducted the first search in the area that had been directly under the worst of the September cloudburst. Farther from the center, the dirt had washed away, but more specimens remained.
"We collected more fossils in four days than I have in the last five years," says a delighted Whistler. "We're getting jaws of a number of different things, including that of a very large camel, Gigantocamelus, a big giraffoid-like camel which, probably adaptively was a giraffe ... a tree-top browser 14 to 16 feet at the head."
Camels, he notes, were strictly a North American invention that only later escaped to Asia (and from there to Africa) and to South America, where their descendants are the llamas and alpacas.
One thing paleontologists almost never find, "Jurassic Park" notwithstanding, is a complete skeleton. This year though, they found a good part of one - a creature called Ustatochoerus, an Oreodont.
"These were a group of exclusively North American [creatures] that have no modern analogue," says Whistler, who, in order to describe it, finds it easier to compare it with what it almost isn't.
"It's very hard to say what an Oreodont was like. It was not like a cow, not like a sheep, not like a dear, not like a pig - but somewhat like all of those things. They're sort of short-limbed, big-bodied ... plant processors." This particular one would have been about the size of a large goat - unlike which it also is - only shorter.
But fossil discoveries have not been limited to the desert.
Rob Bronstein, an artist from Mt. Washington, Calif., a neighborhood on a spur of the Santa Monica Mountains near downtown Los Angeles, was walking his dog along a hillside trail after a February storm when he spotted a rain-dislodged lump of sandstone containing fossilized bones. "I could tell within seconds," said Mr. Bronstein. "There was almost nothing else it could have been." The bones, the museum later confirmed, came from a 10-million- to 12-million-year-old baleen whale - the first ever found in the area.