Over the course of a few decades, if not sooner, hundreds of millions of people may be compelled to relocate because of environmental pressures. (scientificamerican.com)
I suppose this makes some sort of evolutionary sense, in that periods of sleep deprivation might be associated with environmental pressures on early humans and therefore pressure to eat to useful? (sweatscience.com)
Studies by social psychiatrists emphasize the role played by environmental pressures on the development of personality illnesses. (religion-online.org)