How did our species spread across the world? University of York archaeologist Penny Spikins believes that the process accelerated 100,000 years ago because of betrayals of trust. The new paper is published in Open Quarternary.
The dispersal of humans transitioned from a slow pace to a fast one 100,000 years ago. Prior to the change, people would mostly only move across the Earth, allegedly, because of factors pertaining to ecology or demographics; earlier species were more likely to occupy specific regions because they were restricted by environment barriers and due to their slow adaptability. This was no longer a problem after 100,000 years ago, as evidence suggests dispersal was more common. What caused these later communities to displace speedily in spite of the apparent obstacles?
Dr Penny Spikins, a senior lecturer in the Archaeology of Human Origins, believes the main cause to the rapid displacement relates to emotional relationships, and not to population increase or to ecology.
According to her speculations, humans of that time grew more keen to pick out those who cheat and punish them since commitment was viewed as more and more important to their survival. Human’s dark nature would also simultaneously develop. Disputes over betrayed trust would then be more frequent such that rivals would rather be physically away from each other.
Dr Spikins explains that the emotional relationships that would otherwise motivate the people to adhere to each other displayed a darker side pertaining to betrayal – an emotion that still exists today.
As such, distant allies would be ideal to constructing new colonies – this was made easier by having extensive social contacts.
Human emotions were, thus, according to Dr Spikins, the drive that pushed people away from occupied regions of the Earth to other areas that would have entailed great risks and perils – all because of being repelled by betrayals of trust. The need to get away from environments where they could experience physical harm from former friends holding grudges against them, the people made the more difficult choice.
Consequently, populations moved across great deltas of the Indus, Ganges, and deserts, and took to colder regions in the North of Europe, and even went past seas reaching Australia and islands in the Pacific ocean.
“Active colonisations of and through hazardous terrain are difficult to explain through immediate pragmatic choices. But they become easier to explain through the rise of the strong motivations to harm others even at one’s own expense which widespread emotional commitments bring.
“Moral conflicts provoke substantial mobility — the furious ex ally, mate or whole group, with a poisoned spear or projectile intent on seeking revenge or justice, are a strong motivation to get away, and to take almost any risk to do so.
“While we view the global dispersal of our species as a symbol of our success, part of the motivations for such movements reflect a darker, though no less ‘collaborative’, side to human nature,” explains the author.