The phylogenetic roots of human lethal violence


The psychological, sociological and evolutionary roots of conspecific violence in humans are still debated, despite attracting the attention of intellectuals for over two millennia1,2,3,4,5,6,7,8,9,10,11. Here we propose a conceptual approach towards understanding these roots based on the assumption that aggression in mammals, including humans, has a significant phylogenetic component. By compiling sources of mortality from a comprehensive sample of mammals, we assessed the percentage of deaths due to conspecifics and, using phylogenetic comparative tools, predicted this value for humans. The proportion of human deaths phylogenetically predicted to be caused by interpersonal violence stood at 2%. This value was similar to the one phylogenetically inferred for the evolutionary ancestor of primates and apes, indicating that a certain level of lethal violence arises owing to our position within the phylogeny of mammals. It was also similar to the percentage seen in prehistoric bands and tribes, indicating that we were as lethally violent then as common mammalian evolutionary history would predict. However, the level of lethal violence has changed through human history and can be associated with changes in the socio-political organization of human populations. Our study provides a detailed phylogenetic and historical context against which to compare levels of lethal violence observed throughout our history.

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Figure 1: Evolution of lethal aggression in non-human mammals.
Figure 2: Social behaviour and territoriality influence lethal aggression in mammals.
Figure 3: Lethal violence in humans.


  1. 1

    Kelly, R. C. The evolution of lethal intergroup violence. Proc. Natl Acad. Sci. USA 102, 15294–15298 (2005)

    CAS  ADS  Article  Google Scholar 

  2. 2

    Archer, J. The nature of human aggression. Int. J. Law Psychiatry. 32, 202–208 (2009)

    Article  Google Scholar 

  3. 3

    Bowles, S. Did warfare among ancestral hunter-gatherers affect the evolution of human social behaviors? Science 324, 1293–1298 (2009)

    CAS  ADS  Article  Google Scholar 

  4. 4

    Wrangham, R. W. & Glowacki, L. Intergroup aggression in chimpanzees and war in nomadic hunter-gatherers: evaluating the chimpanzee model. Hum. Nat. 23, 5–29 (2012)

    Article  Google Scholar 

  5. 5

    Fry, D. P. & Söderberg, P. Lethal aggression in mobile forager bands and implications for the origins of war. Science 341, 270–273 (2013)

    CAS  ADS  Article  Google Scholar 

  6. 6

    Sussman, R. W. in War, Peace, and Human Nature: the Convergence of Evolutionary and Cultural Views (ed. Fry, D. P. ) 97–111 (Oxford Univ. Press, 2013)

  7. 7

    Morris, I. War! What is it Good For? Conflict and the Progress of Civilization from Primates to Robots (Farrar, Straus & Giroux, 2014)

  8. 8

    Martin, D. L. & Harrod, R. P. Bioarchaeological contributions to the study of violence. Am. J. Phys. Anthropol. 156, (Suppl. 59), 116–145 (2015)

    Article  Google Scholar 

  9. 9

    Keeley, L. H. War Before Civilization (Oxford Univ. Press, 1996)

  10. 10

    Wrangham, R. & Peterson, D. Demonic Males: Apes and the Origin of Human Violence (Mariner Books, 1996)

  11. 11

    Pinker, S. The Better Angels of our Nature (Viking Press, 2011)

  12. 12

    Ferguson, R. B. in War, Peace, and Human Nature: the Convergence of Evolutionary and Cultural Views (ed. Fry, D. P. ) 191–240 (Oxford Univ. Press, 2013)

  13. 13

    Anholt, R. R. H. & Mackay, T. F. C. Genetics of aggression. Annu. Rev. Genet. 46, 145–164 (2012)

    CAS  Article  Google Scholar 

  14. 14

    Huber, R. & Brennan, P. A. Aggression. Adv. Genet. 75, 1–6 (2011)

    Article  Google Scholar 

  15. 15

    Daly, M. & Wilson, M. Homicide (Aldine de Gruyter, 1988)

  16. 16

    Low, B. S. Why Sex Matters: a Darwinian Look at Human Behavior (Princeton Univ. Press, 2010)

  17. 17

    Packer, C. & Pusey, A. E. in Infanticide, Comparative and Evolutionary Perspectives (eds Hausfater, G. & Hrdy, S. B. ) 31–42 (Aldine Transactions, 1984)

  18. 18

    Cubaynes, S. et al. Density-dependent intraspecific aggression regulates survival in northern Yellowstone wolves (Canis lupus). J. Anim. Ecol. 83, 1344–1356 (2014)

    Article  Google Scholar 

  19. 19

    Polis, G. A., Myers, C. A. & Hess, W. R. A survey of intraspecific predation within the class Mammalia. Mammal Rev. 14, 187–198 (1984)

    Article  Google Scholar 

  20. 20

    Lukas, D. & Huchard, E. Sexual conflict. The evolution of infanticide by males in mammalian societies. Science 346, 841–844 (2014)

    CAS  ADS  Article  Google Scholar 

  21. 21

    Archer, J. The Behavioural Biology of Aggression (Cambridge Univ. Press, 1984)

  22. 22

    Fritz, S. A., Bininda-Emonds, O. R. & Purvis, A. Geographical variation in predictors of mammalian extinction risk: big is bad, but only in the tropics. Ecol. Lett. 12, 538–549 (2009)

    Article  Google Scholar 

  23. 23

    Faurby, S. & Svenning, J. C. A species-level phylogeny of all extant and late Quaternary extinct mammals using a novel heuristic-hierarchical Bayesian approach. Mol. Phylogenet. Evol. 84, 14–26 (2015)

    Article  Google Scholar 

  24. 24

    Opie, C., Atkinson, Q. D., Dunbar, R. I. & Shultz, S. Male infanticide leads to social monogamy in primates. Proc. Natl Acad. Sci. USA 110, 13328–13332 (2013)

    CAS  ADS  Article  Google Scholar 

  25. 25

    Garland, T. Jr & Ives, A. R. Using the past to predict the present: confidence intervals for regression equations in phylogenetic comparative methods. Am. Nat. 155, 346–364 (2000)

    Article  Google Scholar 

  26. 26

    Goberna, M. & Verdú, M. Predicting microbial traits with phylogenies. ISME J. 10, 959–967 (2016)

    Article  Google Scholar 

  27. 27

    Shaw, I. & Jameson, R. A Dictionary of Archaeology (Blackwell, 1999)

  28. 28

    Johnson, A. W. & Earle, T. K. The Evolution of Human Societies: From Foraging Group to Agrarian State (Stanford Univ. Press, 2000)

  29. 29

    Allen, M. W. & Jones, T. L. Violence and Warfare Among Hunter–Gatherers (Left Coast Press, 2014)

  30. 30

    Abrutyn, S. & Lawrence, K. From chiefdom to state: toward an integrative theory of the evolution of polity. Sociol. Perspect. 53, 419–442 (2010)

    Article  Google Scholar 

  31. 31

    Bininda-Emonds, O. R. P. et al. The delayed rise of present-day mammals. Nature 446, 507–512 (2007); Corrigendum 456, 274 (2008)

    CAS  ADS  Article  Google Scholar 

  32. 32

    Wilson, D. E. & Reeder, D. M. Mammal Species of the World: a Taxonomic and Geographic Reference, 2nd–3rd edn. (Smithsonian Institution Press / John Hopkins Univ. Press, 1993–2005)

  33. 33

    Finarelli, J. A. & Flynn, J. J. Ancestral state reconstruction of body size in the Caniformia (Carnivora, Mammalia): the effects of incorporating data from the fossil record. Syst. Biol. 55, 301–313 (2006)

    Article  Google Scholar 

  34. 34

    Finlayson, C. et al. Late survival of Neanderthals at the southernmost extreme of Europe. Nature 443, 850–853 (2006)

    CAS  ADS  Article  Google Scholar 

  35. 35

    Arsuaga, J. L. et al. Neandertal roots: Cranial and chronological evidence from Sima de los Huesos. Science 344, 1358–1363 (2014)

    CAS  ADS  Article  Google Scholar 

  36. 36

    Hublin, J. J. The origin of Neandertals. Proc. Natl Acad. Sci. USA 106, 16022–16027 (2009)

    CAS  ADS  Article  Google Scholar 

  37. 37

    Mays, S. The Archaeology of Human Bones (Routledge, 2010)

  38. 38

    Milner, G. R. Nineteenth-century arrow wounds and perceptions of prehistoric warfare. Am. Antiq. 70, 144–156 (2005)

    Article  Google Scholar 

  39. 39

    Service, E. R. Profiles in Ethnology (Harpercollins College Div., 1963)

  40. 40

    War, peace, and human nature: the Convergence of Evolutionary and Cultural Views (ed. Fry, D. P. ) (Oxford Univ. Press, 2013)

  41. 41

    Pagel, M. Inferring the historical patterns of biological evolution. Nature 401, 877–884 (1999)

    CAS  ADS  Article  Google Scholar 

  42. 42

    Münkemüller, T. et al. How to measure and test phylogenetic signal. Methods Ecol. Evol. 3, 743–756 (2012)

    Article  Google Scholar 

  43. 43

    Blomberg, S. P., Garland, T. Jr & Ives, A. R. Testing for phylogenetic signal in comparative data: behavioral traits are more labile. Evolution 57, 717–745 (2003)

    Article  Google Scholar 

  44. 44

    Revell, L. J. phytools: an R package for phylogenetic comparative biology (and other things). Methods Ecol. Evol. 3, 217–223 (2012)

    Article  Google Scholar 

  45. 45

    Freckleton, R. P., Harvey, P. H. & Pagel, M. Phylogenetic analysis and comparative data: a test and review of evidence. Am. Nat. 160, 712–726 (2002)

    CAS  Article  Google Scholar 

  46. 46

    Orme, A. D. et al. caper: Comparative analyses of phylogenetics and evolution in R (v.0.5.2). (2013)

  47. 47

    Martins, E. P. & Hansen, T. F. Phylogenies and the comparative method: a general approach to incorporating phylogenetic information into the analysis of interspecific data. Am. Nat. 149, 646–667 (1997)

    Article  Google Scholar 

  48. 48

    Kembel, S. W., Wu, M., Eisen, J. A. & Green, J. L. Incorporating 16S gene copy number information improves estimates of microbial diversity and abundance. PLOS Comput. Biol. 8, e1002743 (2012)

    CAS  ADS  Article  Google Scholar 

  49. 49

    Nunn, C. & Zhu, L. in Modern Phylogenetic Comparative Methods and their Application in Evolutionary Biology (ed. Garamszegi, L. Z. ) 481–514 (Springer, 2014)

  50. 50

    Piñeiro, G., Perelman, S., Guerschman, J. P. & Paruelo, J. M. How to evaluate models: observed vs. predicted or predicted vs. observed? Ecol. Modell. 216, 316–322 (2008)

    Article  Google Scholar 

  51. 51

    Brand, S. J. Systema Naturae 2000. The Taxonomicon (Amsterdam, 2005)

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The authors thank E. W. Schupp, P. Jordano, M. Lineham, J. A. Carrión, M. Goberna, A. Montesinos, J. G. Martínez, C. Sánchez Prieto, R. Torices, R. Menéndez and F. Perfectti for comments on an early version of this manuscript.

Author information




The study was conceived by J.M.G. Data were compiled by all authors. Analysis was performed by M.V., J.M.G. and A.G.M. All authors discussed the results and contributed to the manuscript.

Corresponding author

Correspondence to José María Gómez.

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The authors declare no competing financial interests.

Additional information

The data used in this study are available in Supplementary Information section 9. Reprints and permissions information is available at

Reviewer Information Nature thanks O. Bininda-Emonds, M. Pagel and M. L. Wilson for their contribution to the peer review of this work.

Extended data figures and tables

Extended Data Table 1 Outcome of the phylogenetic generalized linear model testing the effect of territoriality and social behaviour on the magnitude of lethal aggression in mammal species (n = 1,024 species)
Extended Data Table 2 Outcome of the t-tests assessing difference between the inferred value of lethal violence at each of the chosen ancestral nodes in the mammalian phylogeny and the phylogenetic estimates of human lethal violence
Extended Data Table 3 Outcome of the binomial tests assessing difference between the observed lethal violence in human societies and the inferred lethal violence according to the phylogenetic analysis

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Supplementary Information

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Gómez, J., Verdú, M., González-Megías, A. et al. The phylogenetic roots of human lethal violence. Nature 538, 233–237 (2016).

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