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Two types of aggression in human evolution.

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Wrangham, Richard W.·2018·Proceedings of the National Academy of Sciences
DOI 10.1073/pnas.1713611115PMC PMC5777045
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Abstract

Two major types of aggression, proactive and reactive, are associated with contrasting expression, eliciting factors, neural pathways, development, and function. The distinction is useful for understanding the nature and evolution of human aggression. Compared with many primates, humans have a high propensity for proactive aggression, a trait shared with chimpanzees but not bonobos. By contrast, humans have a low propensity for reactive aggression compared with chimpanzees, and in this respect humans are more bonobo-like. The bimodal classification of human aggression helps solve two important puzzles. First, a long-standing debate about the significance of aggression in human nature is misconceived, because both positions are partly correct. The Hobbes-Huxley position rightly recognizes the high potential for proactive violence, while the Rousseau-Kropotkin position correctly notes the low frequency of reactive aggression. Second, the occurrence of two major types of human aggression solves the execution paradox, concerned with the hypothesized effects of capital punishment on self-domestication in the Pleistocene. The puzzle is that the propensity for aggressive behavior was supposedly reduced as a result of being selected against by capital punishment, but capital punishment is itself an aggressive behavior. Since the aggression used by executioners is proactive, the execution paradox is solved to the extent that the aggressive behavior of which victims were accused was frequently reactive, as has been reported. Both types of killing are important in humans, although proactive killing appears to be typically more frequent in war. The biology of proactive aggression is less well known and merits increased attention.

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Crossref · 10.1073/pnas.1713611115

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  • Human aggressiveness comes in two major forms, reactive (or impulsive) and proactive (or premeditated), each with their own distinctive neurobiology.

    “Human aggressiveness has recently been argued to come in two major forms, reactive (or impulsive) and proactive (or premeditated), each with their own distinctive neurobiology (Wrangham, 2018).”

    From Hypotheses for the Evolution of Reduced Reactive Aggression in the Context of Human Self-Domestication (2019) · cites this paper as Wrangham, 2018

  • The high degree of docility characteristic of humans and domesticated animals depends on a low propensity for reactive aggression.

    “The high degree of docility that is characteristic of humans and domesticated animals depends on a low propensity for reactive aggression, but what relationship it has with proactive aggression, if any, is unknown (Wrangham, 2018).”

    From Hypotheses for the Evolution of Reduced Reactive Aggression in the Context of Human Self-Domestication (2019) · cites this paper as Wrangham, 2018

  • Because proactive and reactive aggression involve different neurobiological mechanisms, under a selective regime of alpha males being executed, the propensity for proactive reaction can remain high while the propensity for reactive aggression declines over evolutionary time.

    “The fact that proactive and reactive aggression involve different neurobiological mechanisms means that under a selective regime of alpha males being executed, the propensity for proactive reaction can remain high while the propensity for reactive aggression declines over evolutionary time (Wrangham, 2018).”

    From Hypotheses for the Evolution of Reduced Reactive Aggression in the Context of Human Self-Domestication (2019) · cites this paper as Wrangham, 2018

  • Prosocial selective pressures have led to a reduction in reactive over and above proactive aggression in recent human evolution.

    “These findings are consistent with the view that prosocial selective pressures have led to a reduction in reactive over and above proactive aggression in recent human evolution (Wrangham, 2018).”

    From Glutamate receptors in domestication and modern human evolution (2020) · cites this paper as Wrangham, 2018

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Research works printed but not linked: 10

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Authors
Wrangham, R. W.
Affiliations
Harvard University (US)
Corresponding author
Wrangham, Richard W.
ORCID
Wrangham, Richard W.
Venue
Proceedings of the National Academy of Sciences
Publisher
National Academy of Sciences
Published
2017-12-26
Volume
115
Issue
2
Pages
245-253
ISSN
  • 0027-8424 (ISSN-L)
  • 1091-6490
DOI
10.1073/pnas.1713611115
PMC
PMC5777045
OpenAlex
W2775958664
Cited by
410
References
162
Citations by year
2026: 26 · 2025: 41 · 2024: 38 · 2023: 92 · 2022: 43 · 2021: 61 · 2020: 66 · 2019: 31 · 2018: 12
FWCI
38.81
Type
journal article
Language
en
Open access
Licence
www.pnas.org/site/aboutpnas/licenses.xhtml (vor, 182 d)
Locations
  • Proceedings of the National Academy of Sciences (publishedVersion)
  • Europe PMC (PubMed Central) (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Evolutionary Psychology and Human Behavior
  • Social Sciences › Arts and Humanities › Philosophy › Violence, Religion, and Philosophy
  • Social Sciences › Psychology › Social Psychology › Primate Behavior and Ecology
Keywords
proactive aggression, reactive aggression, human evolution, aggression, chimpanzees, bonobos, death penalty, self-domestication, war, killing, primate aggression
MeSH terms
Adaptation, Physiological, Aggression, Competitive Behavior, Biological Evolution, Female, Humans, Male, Neural Pathways, Reward, Social Behavior, Violence

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