Arctic Adventures

Fossils in Alaska are helping to construct a picture of climate change over time.

Since the age of 10, after reading Roy Andrews's All About Dinosaurs, Academy research associate Louie Marincovich has been hooked on looking for fossils in remote places. But instead of uncovering dinosaur giants in the Gobi Desert, Marincovich carefully picks away at rocks in search of fossil snails, clams, and other mollusks in some of the coldest, most inhospitable places in North America.

By locating and identifying fossils, Marincovich can reconstruct ancient ocean currents, information that is then used in computer models to map global climate patterns. He and colleagues recently resolved when the Bering Straight first opened and connected the northern Pacific Ocean to the Arctic and northern Atlantic. The last seaway opening in the world to be dated, they pinpointed the event at 5.4 to 5.5 million years ago, or from 1 to 5 million years more recent than previously thought.

Inset map: The Alaska Peninsula where Louie Marincovich and his research team have documented the age of Bering Strait's earliest opening by doing paleontological field work. Photo: Part of the study site, Sandy Ridge, extending from the red backpack in the lower left corner toward the volcanic spine of the Alaska Peninsula. Photo: Louie Marincovich

Eureka! Louie Marincovich (left) and Konstantin Barinov, (right) with the first specimen of Astarte found at the site. Dr. Barinov is a colleague from the Russian Academy of Sciences, Geological Institute, Moscow. Photo: Anton Oleinik

Excavation tools aside, Marincovich depends on gear less typical of scientists. He carries a gun at all times to scare away any aggressive wildlife, and he gets around by helicopter. Living in tent camps hundreds of miles from the nearest town, he's had his share of adventure. He's been charged by grizzly bears, tracked by wolverines, and he survived a helicopter crash when the aircraft's transmission exploded 300 feet off the ground.

Ironically, such life-threatening situations often pay off scientifically in the Great Land. After his pilot grounded the helicopter on a small Aleutian Island to wait out inclement weather, Marincovich discovered a gigantic, 10-million-year-old snail fossil about seven inches long. He named it Tyrannoberingius rex.

“This is the mollusk, Astarte, which we were searching for at Sandy Ridge. This bivalve lived in the Arctic Ocean until Bering Strait opened and allowed it to migrate into the North Pacific. If we found Astarte here, we would know that the strait had opened.” - Louie Marincovich Photo: Louie Marincovich