Is fighting in our genes? A biological theory of warfare

Unthinkable: ‘Humans fight to achieve status and belonging,’ says former soldier Mike Martin

The further you are from conflict the simpler it is to explain. Just ask Mike Martin, a former British army soldier in Afghanistan who is now a London lecturer in war studies.

His experiences in the field and in academia are “unsatisfyingly discordant”, he says, as the reasons given for conflict by armchair experts fail to chime with those he witnessed first hand.

When he got to know people in the Taliban, he discovered their motivation for fighting was less to do with ideology or politics and more to do with upholding family honour or experiencing the exhilaration of conflict.

Martin, whose ideas have crystallised in the book Why We Fight published by Hurst this month, argues that we need to look beyond politics, culture and psychology to war's "biological underpinnings" in order to understand it.


“Humans fight to achieve status and belonging,” he says. “They do so because, in evolutionary terms, these are the surest routes to survival and increased reproduction.”

Many people who have experienced combat say that it was the greatest rush of positive emotions in their lives

Martin makes some intriguing observations in support of this thesis. He cites evidence to suggest that humiliation is a major factor for suicide bombers - specifically male witness to the humiliation of family members. He further highlights that it is rivalry within religions rather than between them that is driving Islamicist violence.

In this manner, he rejects the claim that religion per se lends itself to war, arguing instead that belief in the supernatural helps us to build bigger groups which, evidence shows, are more peace-loving.

Martin, whose paternal family is from Ireland (he also has some views on the “fighting Irish” stereotype), is today’s Unthinkable guest.

Why do you think biology holds the key to understanding conflict?

“There is basically a paradox in war: Why do individuals sacrifice themselves for their groups?

“In many wars, particularly those through evolutionary history when medical care was non-existent, the death rate might have been around a quarter or a third of the combatants.

“I argue that the only evolutionary prizes that offset the high death rate are increased social status, and to maintain their membership of an in-group – that is, not to get ostracised.

“Increased status, and I talk predominantly about men here because the data show that they do all the fighting, has meant for most of humankind’s polygynous evolutionary history that you get more women, and hence can have more children.

“Fighting in a group conflict, or a war, even with the high death rate, represents a lower risk of dying than being cast out from your group. In the Stone Age, ostracisation was a death sentence.

“If that all sounds a bit theoretical, then we should look to the experiences of soldiers going to fight, and actually fighting.

“Many, if not most, people who have experienced combat say that it was the greatest rush of positive emotions in their lives (of course, extreme fear and other negative emotions are also present). That was certainly my experience.

“Moreover, soldiers are drawn to war; they are motivated to seek it out. Now, in biological terms, if you feel positive emotions about a behaviour, that means your ancestors have carried out that behaviour and have benefited in evolutionary terms from it...

“Of course, there are other ways to seek status and belonging, particularly today, but war has been a central way of expressing these evolutionary urges.”

Is it possible to "cure" this impulse to fight?

“We have to be very careful here not to slip into biological determinism. Every physical trait or behaviour that humans have or do is the results of genetics and environment, with very few exceptions. And so this biological, or genetic, impulse to fight is of course shaped by our environments and what we learn.

"The clearest piece of evidence we have for how this relates to war is the huge declines in violence that we have seen in human history, popularised by Steven Pinker in The Better Angels of our Nature.

“Over the last 12,000 years, humans have seen levels of interpersonal violence (that is, murder) and group violence against other groups (that is, warfare) decline - in some cases by over 500 times.

“Today, on average, is the safest time ever to be alive. But over that same period – 12,000 years – we haven’t seen a huge amount of genetic evolution. That works on much slower timescales. And so something in our culture must have limited those levels of violence.

“That thing is our ability to great social groups starting with extended family units, tribes, chiefdoms, ancient city states, etc, all the way up to modern-day multinational alliances. This ability to create structured groups, which by definition have lower levels of violence, is what is curtailing what is a natural predisposition towards competition and violence that humans share with the rest of the animal kingdom.

“So to loop back to your original question: if we really want to limit violence and war, we need to construct a global polity.”

Isn't there a risk, however, that the creation of bigger alliances could bring about conflict? The rise of nationalism in Europe seems to be related to concerns within countries that their national identities are being diluted in the greater whole.

“There is an undeniable correlation over macro human history between lower levels of violence and bigger average groups sizes. But these macro-trends look different when you zoom in. History is a series of saw-teeth: periods of aggregation are followed by periods of disaggregation.

“So if you ask me will we have lower levels of violence, and a bigger average group size – ie regional blocks or a global polity, rather than the nation state – in 1,000 years, or 100 years, I would say yes, we will. But we are clearly going through a period of disaggregation at the moment, so in 10 year’s time, it probably won’t be so positive.

“I think the real question that we are facing at the moment, is how long this period of unravelling – I mean what else is Brexit? – will last. 20 years? It’s very possible.

“And of course, linked to that question, is whether there will be a major, major war during that period. I certainly would not rule that out.”

How should a government best tackle “home grown” extremism?

“These ideas about status and belonging are relevant for all modes of warfare and violence. So too with terrorism. There is a lot of work going on at the moment into the psychology of terrorism. Scholars, and some practitioners, have realised that this idea of ideology driving people to blow themselves up is intellectually bankrupt.

“Coming back to status and belonging, I think the question that governments need to look to answer is how can we create societies that help people feel like they belong more. The modern world is profoundly unsettling, and we need to learn how to sate these very deep evolutionary imperatives.

“In terms of counter-terrorism, practitioners are beginning to see that things like sports clubs, cricket teams, and youth centres, where teenage men - and again it is predominantly men - can help create that sense of belonging to society at a profoundly unsettling time when one is moving from family to wider society.

“These sorts of approaches are much more efficacious than ‘trying to defeat the extremist ideology’, whatever that means.”

I understand you have some Irish roots, and am conscious that certain nationalities can attract stereotypes, such as “the fighting Irish”. Is there any evidence some ethnicities are more prone to warfare than others?

"Yes, my grandfather was born in Newry in 1911 and the family moved to Liverpool just before Partition. Luckily, I now hold British and Irish passports.

“Basically what you are asking is: Do different groups of humans display different characteristics? Yes, of course they do. To be stereotypical, Italians eat pasta, and the Irish drink stout.

“But let’s go back to this earlier idea: that behaviours or traits are a combination of genes and environment. And that certain groups of humans display different behaviours, this is undeniable. In the case of pasta and stout, we can comfortably say that these are learnt behaviours.

“But what about the genetic side of the house? Do some ‘ethnicities’ pursue status and belonging more, and hence fight more, as a result solely of genetic differences? It is possible, but I don’t know of any research that shows this.

“Back to the fighting Irish: it seems to me that this is a racist trope. The British empire was great at these, and came up with all sorts of martial races, and servant races. If there was such a big difference between the British and the Irish that came down to their ‘races’ why are there such similar levels of violence in their societies today?”