Brief

Study finds mild aggression and lethal violence evolved separately in primates

Analysis of 100 primate species suggests everyday aggression does not predict lethal violence, challenging the idea that humans are hardwired for killing.

By Felo News Desk · Published Wed, 07 Oct 2026 19:28:05 GMT

Researchers at the University of Lincoln have published a study in Evolution Letters that questions the assumption that everyday aggression inevitably leads to lethal violence. The team, led by Professor Bonaventura Majolo with Dr. Samantha Wakes and Professor Marcello Ruta, examined patterns of aggression across 100 primate species, including humans.

Their analysis identified five forms of aggression, ranging from routine disputes to lethal attacks such as adult rival killing and infanticide. While some species showed moderate links between different lethal behaviors, none of the lethal forms correlated strongly with mild aggression. In other words, species that frequently engage in minor conflicts are not necessarily more likely to kill competitors.

Majolo said, "Our study shows that the evolution of aggression follows more complex patterns than earlier models proposed, and it is biologically inaccurate to rank species on the basis of a general propensity for aggression." The findings add a new layer to the long‑running debate over whether violence is an inherent part of human nature, suggesting that social and cultural factors may play a larger role than previously thought.

Key facts

The study examined aggression in 100 primate species, including humans. (sciencedaily.com)
Mild aggression and lethal aggression were found to be largely unrelated. (sciencedaily.com)
Lethal behaviors such as adult rival killing and infanticide showed only moderate association with each other. (sciencedaily.com)
The research was published in the journal Evolution Letters. (sciencedaily.com)
Lead author Professor Bonaventura Majolo said aggression evolution is more complex than a single scale. (sciencedaily.com)