Scientists Link Humans To The Extinction Of Ice Age MammalsContact: Finnegan, Lisa
NEW YORK — Fordham paleoecologist Guy Robinson does not believe mammoths, mastodons and other Ice Age Mammals were killed off by a natural disaster. Unlike the asteroid impact which led to dinosaur extinction 65 million years ago, he thinks that North America's large mammals were brought down by something closer to home.
"My suspicion is that humans were a key factor in the extinction of mastodons in New York at the end of the last Ice Age" he said. "When you look at the situation globally the disappearance of a whole range of large mammals, reptiles and flightless birds seems to follow the first arrival of people. I'm almost certain that that's the case here in New York."
Robinson, a graduate student working in the Department of Biological Sciences with David Burney, Ph.D., and Lida Pigott Burney, will present his findings at a meeting of the Geological Society of America in March.
While many scientists of this type are preoccupied with digging up bones and large fossils, Robinson also works with sediments found under water. Specifically, he looks at microfossils of pollen, algae, mold spores and charcoal particles. Combined with radiocarbon dating, he says this can tell the story of vegetational changes and fire history over many thousands of years. Sudden changes in the pattern of fires can show when humans began setting fires in the region."
You can get a picture of how many animals were around at the time, and can piece together what the environment was like," Robinson said. "New York State is really an ideal place to study these questions. We have one of the highest densities of mastodon finds in the U.S. and the preservation of fossil material is excellent."
According to Robinson, North America was once loaded with wild elephants, camels, giant beavers, horses and giant ground sloths. What they all had in common, was that none of them had ever seen humans before and like the Galapagos tortoises, they were all easy to kill.
"It's important to know that we as humans have had a profound effect on our environment going back to the earliest prehistoric times," he said. "People tend to assume that when Europeans arrived here, they found a pristine landscape. But by that time, 75 percent of all the animal species over 100 pounds were extinct. They were gone."
Robinson and Burney feel that talk of conservation is not enough and that any restoration efforts should be informed by pre-human history.
"We need to learn our past, so as not to repeat it," Robinson said.
Founded in 1841, Fordham is New York City’s Jesuit University. It has residential campuses in the north Bronx and Manhattan, a graduate center in Tarrytown and the Louis Calder Center Biological Field Station in Armonk, N.Y.