As climate change progressively causes more heat waves, droughts, floods, hurricanes, crop failures, and wildfires, we are already seeing unprecedented human migration, which is expected to grow exponentially over the next two decades.
The current state of scientific research on these trends is very nicely summarized in a Special Report by ProPublica.org, a non-profit investigative reporting organization. Here is the link to the reports, which includes a climate migration map for the United States, showing which areas will become uninhabitable because of climate change.
There is also an excellent video that summarizes the findings of the report. Its author, Abrahm Lustgarten, provides a sobering yet fact-based analysis of what we can expect in North America and globally during the next few decades. He explains how the mass migration from Central America is directly caused by climate change. Here is that video.
The extreme disruption of climate change is already having a powerful effect on the velocity and trajectory of human evolution.