Originally shared by David Brin

An amazing survey of cause-of-death of members of a wide variety of mammal species finds that a likely baseline murder rate among humans would be around 2 percent. The authors used the fact that closely related species usually show similar rates of interpersonal violence to predict a 2 percent rate of lethal violence among humans. That means that 2 out of every 100 human deaths would be a murder taking into account only our place on the evolutionary tree, and nothing about political pressures, technology or social norms.

In comparison, among mammals in general just 0.3 percent of deaths are murders. For the common ancestor of primates, the rate is 2.3 percent.

With 2 percent as a human baseline, we come across as both uncommonly peaceful for primates and uncommonly violent for mammals.

“Rates of homicide in modern societies that have police forces, legal systems, prisons and strong cultural attitudes that reject violence are, at less than 1 in 10,000 deaths (or 0.01%), about 200 times lower than the authors’ predictions for our state of nature.”

The champion killers of their own kind? Meerkats. Hakuna Matata, man.