When attacks involve lethal risks, men in tribal societies tend to desert or avoid fighting unless shamed or physically punished, as in Mathew and Boyd's study of Turkana warfare.

The claim has two parts: (a) in tribal societies, men facing lethal risks in attacks tend to desert, hang back or avoid fighting unless they are shamed or physically punished, and (b) this is illustrated by Mathew and Boyd's study of Turkana warfare. True: the literature supports (a) as a general tendency, and Mathew and Boyd's study reports desertion or cowardice being curbed by shaming or physical punishment, consistent with the claim. Mostly true: both parts hold, with a minor mischaracterisation of a detail of the study. Mixed: one part holds and the other does not, for example where cowardice and sanctions are documented but the study's main finding is portrayed in a materially misleading way. Mostly false: the claim takes a real element, such as sanctions against cowardice, out of context to suggest a general tendency to desert that the cited study or the wider literature contradicts. False: the cited study does not discuss desertion or sanctions, and the wider evidence shows tribal warriors do not tend to avoid risky fighting.

Set before the research began.

1. E1 Study of East African group suggests punishment could sustain large-scale cooperation among strangers Phys.org · 14 June 2011

   “Cowardice and desertions occur, and are punished by community-imposed sanctions, including collective corporal punishment and fines.”

2. E2 Study of East African group suggests punishment could sustain large-scale cooperation among strangers Phys.org · 14 June 2011

   “Based on the interviews, they found that at least one man ran off before the raid even began, forty three percent of the time, and forty five percent of the time someone performed badly enough during a raid to warrant some sort of punishment.”

3. E3 An Evolutionary Theory of Large-Scale Human Warfare: Group-Structured Cultural Selection Evolutionary Anthropology (Zefferman and Mathew) · 2015 Own record

   “Warriors risk serious injury and death. One percent of combatants are killed per raid and 50% of the males who survive to adulthood die in warfare.”

4. E4 Intergroup Aggression in Chimpanzees and War in Nomadic Hunter-Gatherers Human Nature (Springer) · 3 March 2012

   “According to this idea chimpanzees and humans are equally risk-averse when fighting. When self-sacrificial war practices are found in humans, therefore, they result from cultural systems of reward, punishment, and coercion rather than evolved adaptations to greater risk-taking.”

E1, a news report on Mathew and Boyd's Turkana warfare study, reports that cowardice and desertion occur and are punished by community-imposed sanctions, including collective corporal punishment and fines. E2 reports that in the study's interviews at least one man ran off before a raid 43% of the time, and that 45% of the time someone performed badly enough during a raid to warrant punishment. E4, a 2012 peer-reviewed article, describes the view that humans are risk-averse when fighting and that self-sacrificial war practices rest on cultural systems of reward, punishment and coercion, which supports the general tendency in part (a). Both parts of the claim are consistent with the evidence.