Climate changes how species interact with one another-and not just today. Scientists are studying trends from fossil records to understand how climate change impacted the world in the ancient past and to identify ways to predict how things may change in the future, according to a new study by University of Maryland Center for Environmental Science researcher Matt Fitzpatrick and colleagues published in the August 2 issue of Science.

Climate change has occurred repeatedly throughout Earth's history, but the recent rate of global warming far exceeds that of any previous episode in the past 10,000 years or longer. Knowing how climate change altered the interactions between plants and animals in the past may help us understand whether there are identifiable patterns that could give us clues into what will happen in the future.

"Looking to the past is one of the few ways ecologist have for understanding how natural systems respond to climate change," said Fitzpatrick of the Center's Appalachian Laboratory. "When we look to the fossil record, from hundreds of millions of years ago to near present day, we see episodes of climatic change and biological upheaval, and we see similar patterns."

For example, changes in temperatures may force certain animals to move to different territories and new predatory-prey interactions my result. Some may go extinct. Changes in carbon dioxide levels may make it easier for new plants to take over the landscape, such as more shrubs growing in the Arctic. All of these changes shake up how the ecosystem and food webs work.

"Because these patterns emerge repeatedly and largely regardless of place and time," Fitzpatrick says. "It suggests that similar underlying processes drive how natural systems respond to climate change and provides a glimpse of what could be in store for the future."

The worry is that the rate of current and future climate change is more than species can handle naturally. "People are comfortable with the way things are now - we know where to plant crops, where to get water," said lead author Jessica Blois of the University of California, Merced. "We want to know how to respond to the changes that are happening, but if the future is highly novel, then it's also hard to predict."

"Climate Change and the Past, Present and Future of Biotic Interactions" is published in the August 2 issue of Science. Authors include Jessica Blois of the University of California, Merced, Phoebe Zarnetske of Yale University, Matt Fitzpatrick of the University of Maryland Center for Environmental Science and Seth Finnegan of the University of California, Berkley.