This study is an extraordinary example of fossils being used to show the impacts of climate and human disturbance on an ecosystem in Utah. Interestingly, the study has found that the small mammal community could cope with changes in climate but not with changes in land-cover in the 1800s. We see this trend continuing with recent reports that we are entering a sixth global mass extinction event as a result of human overpopulation:

http://www.theguardian.com/environment/2015/jun/19/humans-creating-sixth-great-extinction-of-animal-species-say-scientists