December 1, 2005
Vol. 25 No. 6

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    Fossil record has valuable information that impacts environment

    By Steve Koppes
    News Office

    Susan Kidwell instructs students during a fieldwork trip.

    Susan Kidwell has a new motto about paleontology: “It’s not just for evolution anymore.”

    Paleontology has gained fame for its evolutionary studies on dinosaurs, trilobites and other ancient beasts, but it also can help scientists better understand the biological effects of future environmental change that confront society today, according to a report the National Academy of Sciences issued last summer.

    “These aren’t just academic issues,” said Kidwell, a co-author of the report and the William Rainey Harper Professor in Geophysical Sciences and the College. “This is really a new way of looking at the geological record. I don’t think everyone in the earth science community realizes just how much we’ve learned in the past couple of decades about all the ways we can get unique ecological insights out of the fossil record.”

    As a member of the National Research Council’s Board on Earth Sciences and Resources, Kidwell proposed the National Academy project in 2000. The 12-member NRC committee consisted of paleontologists, ecologists and other scientists from across the country. The report is titled The Geological Record of Ecological Dynamics: Understanding the Biotic Effects of Future Environmental Change.

    The report shows how geological techniques might help address major environmental challenges confronting society today. These challenges include ecological impacts of climate variability, land use and habitat alteration, and invasive species.

    The report recommends that federal agencies undertake three initiatives that have high scientific and societal relevance:

    • 1. Use the geological record as an ecological laboratory.

      Biologists today have access to only a small percentage of life on Earth as a basis for their experiments. “Ninety-five percent of all species that have ever existed in the history of life are extinct,” Kidwell said. But scientists can compare the workings of ecological communities today to the fossil record.

      “When rules governing modern communities also prevail in the geologic past, despite completely different community compositions and physical conditions, this is a sure sign that general principles have been pinpointed,” she said. “This is what we need to test many ecological theories, before we apply them to present-day challenges.”

    • 2. Study ecological responses to past climate change to help forecast the future.

      Fossils have long been used to reconstruct major environmental changes on Earth. Now, geochemical techniques can reveal changes that have occurred in temperature, rainfall and other physical conditions in the past. “There’s really exciting work going on right now concerning the time lags between climate change and species migration or extinction, and whether communities shift en masse or disintegrate,” Kidwell said.

    • 3. Identify the ecological legacies of societal activities.

      Today it is difficult for scientists to sort out natural ecological variations from changes triggered by humans and their technology. But the geologic record can provide “a longer-term perspective of what is natural,” Kidwell said, before humans came on the scene. This perspective can help policy makers develop strategies for conservation and restoration.

    The report noted that the existing Long-Term Ecological Research projects could be a springboard for research on the three initiatives. The National Science Foundation has funded Long-Term Ecological Research projects at 26 sites over the past quarter century for decades-long biological monitoring of estuaries, marshes, lakes and other habitats. Analyzing sediment cores and other geological data from these same sites would provide a valuable deeper time perspective to these studies, the NRC report said in its list of recommendations.

    Even more valuable would be a series of new Geologic Time Ecological Research projects, which the report proposes. This new program would be comparable to the Long-Term Ecological Research program, but lodged entirely in the past. It might, for example, study the geologic history of oceanic islands to establish how the repeated invasion of mainland species affects them. Or it would focus on a specific time interval, such as the Pliocene Epoch, which ended 1.8 million years ago. The Pliocene is the most recent epoch of geologic history that exhibited the warm climates that also may characterize Earth’s immediate future, Kidwell said.

    The National Science Foundation and the U.S. Geological Survey, both of which funded the NRC report, and other agencies already have provided some support to projects involving the collaboration of geologists and biologists. But the report recommends an even greater emphasis on integrating the two sciences, which now follow very different styles of research. Biologists do controlled experiments, while geologists and paleontologists depend on observational data of past events.

    Consequently, Kidwell said, she is eager to get the NRC report into the hands of graduate students and post-doctoral researchers. “They’re not yet set in a particular way of doing science.” Kidwell and the other authors of the report are aiming not only to advise federal agencies but also to inspire up-and-coming young scientists. Indeed, students at Chicago are already exploring the idea of applying paleontology to conservation issues.

    “They call it conservation paleobiology,” she said.