05/05/2012 06:02:00 PM EST
Noise Can Alter the Composition of an Ecosystem
Prior posts have reviewed the wide variety of "selection factors" than can drive evolution in a species. Now it appears that noise can alter the makeup of an entire ecosystem.
Researchers have found that noise can drive away some species and sometimes encourage others, which in turn can influence the presence or absence of plants. Researching a northwest New Mexico wood which had noisy gas wells, researchers found a reshuffling of birds and small mammals, which in turn changed the odds of success for crucial steps in plant reproduction. They noted, for example, that pollination by hummingbirds, important for certain wildflowers, increased. In contrast, birds that were likely to spread pine seeds without eating them all gave way to mice that ate more of their seed cache. Thus, they noted that whole ecosystems could be restructured by noise.
Noise also was found to matter to nesting birds. Although approximately the same absolute number of birds nested around both roaring and quieter wells (the roar being the result of which wells had compressors), the quieter areas had a greater variety of bird species. Species variety in term influences the impact on food sources, which in turn impacts what plants and trees come to be in an area.
The study can be found at http://rspb.royalsocietypublishing.org/content/early/2012/03/15/rspb.2012.0230.