Climate Relicts in Ecosystem Islands May Reveal History of Climate Change

When you hike through oak and hickory forests, the last thing you would expect to see would be prickly pear cacti. Yet plants like these are relicts from a time gone by, surviving in small pockets. Now, scientists are taking a closer look at these relicts in order to better understand how ecological communities are affected by climate change.

In the Ozarks, rocky and well-drained slopes can create habitat "islands" within the surrounding forest known as glad ecosystems. These glades can preserve isolated communities of cacti and other desert and prairie species that once dominated the area during the Hypsithermal, a period which occurred four to eight thousand years ago.

Now, scientists are beginning to realize that these climate relicts could be used as "natural laboratories" when it comes to studying the evolution of single plant species. In fact, they can show researchers what type of habitat was prevalent in an area in the distant past. These isolated climate communities can show a bit more about the long term effects of climate change.

"We're learning that you often can't just go out and preserve a single species," said Scott Woolbright, one of the researchers, in a news release. "Interactions with other species can play very important roles in species survival. If we don't take those interactions into account, we can miss things that are really important."

These relicts could play a huge role in future research. By using them, scientists could investigate climate-driven changes in species interactions. That said, many of these climate relicts are threatened by small population size and ongoing environmental change. This means that studying them now may be crucial in terms of learning all scientists can about these species and climate history.

The findings are published in the journal Trends in Ecology & Evolution.