Saturday, October 01, 2016

Bloody legacy

A new article in a top-ranking scientific journal (Gómez, J. M., M. Verdú, A. González-Megías, and M. Méndez. 2016. The phylogenetic roots of human lethal violence. Nature, doi:10.1038/nature19758, Published online, 28 September 2016) deals with the tendency of humans to kill other humans in evolutionary perspectives. It is discussed extensively by Prof. Jerry Coyne at his site, from where I learned about it.

Using data from other published articles, the authors calculated for more than 1000 animal species the proportion of deaths that are due to killing by other members of the same species. They found that related species had similar levels of such "lethal violence", and that it was higher in social and territorial species such as carnivores and (especially) primates.

Levels of deadly violence were also estimated for different human populations - more than 600, dating from the Paleolithic to the present. According to the authors, the ancestral human condition corresponded to about 2% deaths caused by other humans. However, depending on the social organization, this proportion could be moved both up and down. Some primitive societies, esp. those that are still retaining their primitive organization, were found to have higher levels of violence, while states have lower levels.

I know that we cannot hope ever to build a society completely free of lethal violence. The bloody legacy of our evolution is inscripted in human genes and cannot be erased. However, we can and must try to control it. We must strive for a society that discourages killing in every possible way. We have already advanced on this path, and this gives hope. We must continue. Every life that is preserved is worth the effort.