"I've Got to Get the Hel Out of Here, or They'll Kill Me!"

[Recusant]

An archaeologist who has been specializing in "behavioural implications and evolutionary significance of structural dynamics in human social emotions" has come up with a hypothesis to explain the change in human migration patterns that occurred about 100,000 years ago. Broadly, it has to do with moral outrage and its consequences.

"Human nature's dark side helped us spread across the world" | University of York

New research by an archaeologist at the University of York suggests that betrayals of trust were the missing link in understanding the rapid spread of our own species around the world.

Dr Penny Spikins, of the University's Department of Archaeology, says that the speed and character of human dispersals changed significantly around 100,000 years ago.

Before then, movement of archaic humans were slow and largely governed by environmental events due to population increases or ecological changes. Afterwards populations spread with remarkable speed and across major environmental barriers.

But Dr Spikins, a senior lecturer in the Archaeology of Human Origins, relates this change to changes in human emotional relationships. In research published in Open Quaternary, she says that neither population increase nor ecological changes provide an adequate explanation for patterns of human movement into new regions which began around 100,000 years ago.

She suggests that as commitments to others became more essential to survival, and human groups ever more motivated to identify and punish those who cheat, the 'dark' side of human nature also developed. Moral disputes motivated by broken trust and a sense of betrayal became more frequent and motivated early humans to put distance between them and their rivals.

[Continues . . .]

The full paper: "The Geography of Trust and Betrayal: Moral disputes and Late Pleistocene dispersal" | Open Quarternary

Abstract

The explanations for a rapid dispersal of modern humans after 100,000 BP remain enigmatic. Populations of modern humans took new routes – crossing significant topographic and environmental barriers, including making major sea crossings, and moving into and through risky and difficult environments. Neither population increase nor ecological changes provide an adequate explanation for a pattern of rapid movement, including leaping into new regions (saltation events). Here it is argued that the structural dynamics of emotionally complex collaboration and in depth moral commitments generates regular expulsion events of founding populations. These expulsion events provide an explanation for the as yet elusive element to dispersal. Alongside cognitive and cultural complexity we should recognise the influence of emerging emotional complexity on significant behavioural changes in the Palaeolithic.

[Icarus]

Conventional wisdom has it that migration resulted from the quest for better hunting, more readily available water, and more fertile soil for early agricultural efforts.  Of course the travelers may have been obeying " the grass is greener on the other side" notion. Not only that but some of we humans are infected by wanderlust as in: what's on the other side of that mountain? It is a near certainty that some of the movements were prompted by the need to escape from dangers or disagreements with certain of their peers.

[Recusant]

Dr. Spikins may be putting too much weight on her hypothesis, but as you say, it's plausible enough that "changes in human emotional relationships" had a possibly very significant effect on the level of human migration.