Animal populations crashed — and likely early human populations as well. (williamcalvin.com)
In fact, early human populations with much less advanced technologies had far larger individual land footprints than societies have today. (winsol.org)
Ash Parton and colleagues fall into the second camp, writing, «The dispersal of early human populations out of Africa is dynamically linked with the changing climate and environmental conditions of Arabia. (sciencedaily.com)