Computer models developed by the University of Chicago and Argonne National Laboratory predict that hotter, drier conditions in North America will limit the growth of a fungus that normally curbs the spread of the spongy moth, an invasive species that has caused millions of dollars in damage to forests.The research, published in Nature Climate Change, emphasizes the importance of accounting for multiple organisms and their interactions when predicting the potential impacts of climate change, as warmer temperatures cause unexpected domino effects in ecosystems.“The vast majority of previous climate change studies look at individual organisms, but a small amount of climate change can have a big effect when you compound it across multiple species,” said Greg Dwyer, PhD, Professor of Ecology and Evolution at UChicago and senior author of the new study. “So, computer models are crucial for understanding the effects of climate change on species interactions.”Small changes lead to big impactsThe spongy moth (Lymantria dispar) was first introduced to the hardwood forests of New England in 1869. Native to Europe, female moths lay eggs on surfaces like branches, stacked firewood, and outdoor furniture. The eggs tend to come with these objects when people move them, so the insect has spread far from where it was first accidentally released in Massachusetts. Spongy moth caterpillars feed on the leaves of trees and shrubs, especially oak trees. For decades after their introduction, the caterpillars carved a path of destruction through forests, defoliating and killing trees by the acre.In 1989, a lethal infection caused by the fungus Entomophaga maimaiga began spreading among spongy moths. This fungus is also not native to North America, but no one knows for sure how and when it arrived. It might have been introduced deliberately to control the moths, or it might have been accidentally brought into the US from Japan, where it originates. Nevertheless, it has managed to keep spongy moths in check ever since, sparing millions of trees.Want more breaking news?Subscribe to Technology Networks’ daily newsletter, delivering breaking science news straight to your inbox every day.Subscribe for FREEAnother pathogen, the nucleopolyhedrovirus (NPV), can also keep the insect in check, but it needs large populations to spread. The natural advantage of the fungus is that it can grow and infect moths in small numbers before too much damage has been done, but only if conditions are cool and moist.“Even small reductions in mortality rate for the moths lead to big increases in defoliation,” Dwyer said. “If they don’t get killed off when they’re at low density one year, then the next year they’ll be back at higher density. You get this multiplication process going on.”Not pessimistic enoughDwyer has spent his career modeling interactions among infectious diseases and various species, from wild rabbits to insects. In 2004, in one of his first publica
Mer. Gen 8th, 2025
