There's no time like the present to study ancient history

By Chris Denina
Staff Writer

Tyrannosaurs, stegosaurs and brontosaurs are babies compared to the great granddaddies of time that paleobiologist David Bottjer unearths.
Bottjer's research as a professor of earth sciences takes him to the mountain ranges of Eastern California and Nevada to look for fossils that easily outdate dinosaurs by hundreds of millions of years.
"Right now, the oldest thing we're studying is probably between 550 to 600 million years old. They're fossils of probably the earliest animals on Earth," Bottjer said. Dinosaurs of the Mesozoic Era, by comparison, merely range around 65 million years old.
The kinds of creatures that Bottjer studies look "pretty strange ... They're sort of just earlier versions of the things we find on Earth nowadays," he said. "They look and behave quite differently. Most live on the sea floor. They look more like seashells and sea urchins -- the invertebrates you find when you go tide pooling."
As a child, tide pooling trips to the beach was the hobby that got him turned on to digging up weird-looking things. Today, he and his fellow paleobiology scientists take weekend excursions and summer trips to the mountains to find fossils that answer particular scientific questions.
"For instance, the history of life has been punctuated by things like mass extinction. The dinosaurs all died out because of a mass extinction. We try to find out how life recovers after that," Bottjer said.
He also takes his classes on digs for hands-on experience on two-to-three-day weekend trips. Serious research, however, conducted by Bottjer and his colleagues, can take two or three weeks.
In both cases, they use sledgehammers, chisels and hammers to break the fossils out of millions-of-years-old rock, which he said is as hard as cement because they're so old. "It's more like a quarry than a dig."
"We look at the earliest evolution of animals on Earth. We can go to mountain ranges in Eastern California and Nevada that tell us about that time. Pretty soon we're off the paved highway and on the dirt road," he said.
"There isn't really something like a `Thomas Guide' to a lot of these places," Bottjer said. "You put on your hiking boots and bring lots of maps. Nowadays, we have GPS (Global Positioning System), but it's pretty much maps because most of these places were located before we had GPS. In a way, it's like finding a needle in a haystack."
Once they complete their research and find the answers they are looking for, Bottjer and his colleagues present their results to other scientists at national conventions. But there's a commercial application beyond the purely academic pursuit of information.
"Most of the natural resources we use in society come from rocks that contain fossils. There's an economic incentive to know about fossils. It can give you a lot of information about where to look for oil," he said.
But for Bottjer, whose childhood hobby was beach combing, the academic pursuit is more rewarding than finding such natural resources as oil, phosphate and uranium for corporations.
What sorts of fossil finds are so rewarding?
Once-slimy things: "mollusks, clams, snails -- all the things you'd find when you're beach combing today," he said.


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