The Japan Times
February 11, 2002
NATURE
HUGH & MIDORI PAXTON

California prehistory mired in La Brea tar pits

LA BREA, Calif. — The world, 40,000 years ago — The weather's perfect. A warm breeze from the Pacific rustles the palms, there's the sharp tang of juniper and pine in the air, and the nameless mountains rising beyond the plain that will one day be Los Angeles, glow mauve in the early morning sun.

Enter victim No. 1. A large camel. It's wary. There are hungry American lions around. But the camel is thirsty, and that gleaming pool of water is irresistible. If this parched beast had approached the pool in winter, when cooler temperatures ensured that the asphalt that lies beneath was harder, the ensuing scene would not have occurred.

But it's summer. The asphalt's like glue, and the camel is soon mired, bellowing and sinking.

This is when the carnage really starts. Victim No. 2 is a saber-toothed tiger. Drawn by the distressed honks of the trapped camel, it starts feeding and then finds its feet stuck in the asphalt.

Dire wolves arrive, attracted by the commotion. Despite their name, these wolves are no larger than contemporary gray wolves and are actually shorter in the leg. Some tear flesh from both trapped animals, then flee. Others become embedded in the black glue. Vultures and condors land. Wings get stuck, talons clogged.

There's hooting and hollering, then the whole lot — predators, prey and scavengers — sink and settle in the glutinous murk.

All around this deathtrap are animals in profusion. It's like the Serengeti here. Some species you'd recognize in an instant — coyotes, blue jays, skunks. Others, such as giant ground sloths and mastodons, are altogether more exotic as they graze the plains around the bubbling pitch pits.

200 years ago — The weather's a lot drier, but the Pacific breeze is about the same. Likewise the palms, juniper, coyotes, skunks, etc. The American lion, though, like the ancient camel, is no more. Imperial mammoths, native llamas and three-toed horses are also extinct and have been for centuries.

The principle causes of extinction were global cooling and the arrival of the original Americans, who crossed the ice bridge from Mongolia and then ate their way south from the Bering Strait to the tip of Patagonia.

The pitch pits, however, are still up to their tricks.

Jose Longinas Martinez, a traveler, describes in his journal of 1802 "more than 20 springs of liquid petroleum" and a great lake of pitch. "These phenomena," he writes, "present an astonishing and frightful aspect, reminding one of the pictures painted of the infernal caverns.

"When the heat of the sun forces birds to seek water, they fall into the lake, which seems to them to be water," Martinez continues, "All the birds that come thus are caught by the feet and wings until they die of hunger and thirst. The same disillusionment overtakes rabbits, squirrels and other animals. For this reason, the gentiles are very careful to explore these places in order to hunt without work."

By gentiles, Martinez meant the native people. For millennia, they used the pitch to decorate beakers and caulk leaks. And one, at least, used them to hide evidence of a murder.

152 years ago — The village of Los Angeles is well-established. Commerce booms. A certain Maj. Henry Hancock is engaging a schooner and has plans to pave the streets of San Francisco with pitch. Dry chunks are sold as fuel at $4 a ton. And as the pitch is dug out, the bones of the past emerge. But it will be years yet before any serious efforts are made to unearth the vast skeletal treasury that lies in the pits now known as La Brea.

97 years ago — The excavations have begun in earnest. Both amateurs and scientists labor in pits and tunnels up to 15 meters deep, threatened by gas escaping from vents, shoring up sagging walls, using dynamite and dodging cave-ins. It's hard, filthy work; they call it "mucking."

But the results are staggering. Excavators L.E. Wyman and E.J. Fischer remark, "The way the bones are packed into this matrix and the quantity of them are incredible." Pit 4 alone yields "286 skulls; 90 tigers, 174 wolves, eight camels, seven lions and 14 horses." In Pit 61, 60 percent of all remains are saber-toothed tigers. A young Indian woman, the murder victim, is chipped out painstakingly and, like all the other remains, is crated and shipped out by wagon to the storage warehouses.

Now — A fraction of the La Brea finds are on display at the Los Angeles County Museum of Natural History, though there's still enough to keep a visitor busy — even if, as one study found, the average person devotes just 2.7 seconds looking at a museum exhibit. Philanthropist George C. Page designed the museum to try and prolong this dismal statistic. He's done a good job.

Kids struggle with a machine that simulates the "suck-you-down" power of liquid pitch. Or tentatively stroke the femur of a giant sloth in the "touch bone" exhibit. There are life-size models of gargantuan mammals locked in struggle and beautiful murals depicting the California of long ago. There are windows through which one can watch paleontologists cataloging thousands of saber-toothed tiger ribs. And of course, there are skeletons galore. Short-faced bears, Dire wolves, mammoths, vultures and the horse, which did very well in America for some 50 million years before being hunted into extinction. (And then being reintroduced and doing very well all over again.)

Outside the museum in the newly designed park, in the heart and smog of downtown L.A., the asphalt pools still spit and bubble. A fascinating, if treacherous, constant in continually changing California.


The tar pits of La Brea trapped prehistoric creatures such as the imperial mammoth (left and center) and the saber-toothed tiger (right) © PAXTON IMAGES