A few years ago, researchers discovered that in areas polluted by human-made noise, a species of hummingbird seemed to increase in population, while a jay species seemed to decrease.

The same researchers now report that noisy areas have more flowers, but fewer trees. The findings appear in the current issue of the Proceedings of the Royal Society B: Biological Sciences.

It’s a domino effect, said Clinton D. Francis, an evolutionary ecologist at the National Evolutionary Synthesis Center in Durham, N.C.