Most research on climate change ecology is limited to the impacts of a single climate variable, such as temperature or water availability, on one trophic level at a time — and often on a single species. For instance, many studies have shown that increasing carbon dioxide levels can increase plant growth. While such studies can provide important insights, this narrow approach can also be ecologically and climatically unrealistic, according to a new paper by Yale researchers. Writing in the journal Trends in Ecology & Evolution, two Yale scholars make the case that overly simplistic studies or experiments avoid the inherent complexity and interconnectedness of natural systems. As a result, they can yield erroneous climate predictions, they write. “Most of the climate change ecology research out there has been picking the low-hanging fruit for many years,” said Adam Rosenblatt, a postdoctoral fellow at the Yale School of Forestry & Environmental Studies (F&ES) and lead author of the paper. “Often they study the effects of one type of variable. That’s obviously useful but it’s not realistic because in nature nothing exists in isolation.” The paper was co-authored by Oswald J. Schmitz, the Oastler Professor of Population and Community Ecology at F&ES. “The tradition in experimental analysis of climate change effects on ecosystems is to focus on one variable at a time. But this leads to a rather piecemeal and fragmentary picture of ecosystem functioning,” said Schmitz. “We propose a more integrative approach. While more complex, it will, nonetheless, help to unveil a more complete and coherent portrait of how real-world climate change will…