But a new study finds that the opposite is actually occurring as climate change decreases the numbers of potential colonizers. In the face of accelerating anthropogenic climate change, scientists expect the overall number of species being replaced in Earth’s various ecosystems to increase. The X-factor is the widespread degradation of the environment caused by anthropogenic climate change. The authors caution that ecosystems are immensely complex and estimates of total species turnover can be affected by short-term climate variability (i.e. But the evidence suggests that environmental shifts related to climate change are proving even more deleterious to Earth’s ecosystem dynamics than scientists expected.