Nov 11, 2007

Sinuous Sunday - The Sharp End of Altruism

People bitch a lot about violence featured in movies and TV, but ignore a worse problem – how the sort of real (not make-believe) violence known as war is often associated with religion.

Now there may be a better theoretical understanding of how and why this association between religion and war may exist. Two articles in the October 26, 2007 issue of Science discuss evolutionary simulations which show that war drives the joint evolution of altruism and hostility to outsiders. Based on (but going beyond) this work, we will see how religion may be associated with warfare.

The first "perspectives" article gives an overview:

The Sharp End of Altruism

Which would you prefer: a society of selfish but tolerant freetraders, or a warrior society in which people help one another but are hostile to outsiders? If you value both altruism and tolerance, neither seems ideal. Societies of tolerant altruists, however, are exceedingly rare in the simulation presented by Choi and Bowles on page 636 of this issue. Instead, altruism flourishes only in the company of outgroup hostility (parochialism), with war as both the engine of this coevolutionary process and its legacy. For a compatriot, the parochial altruist who risks his life is a shining knight, whereas the outsider encounters the sharp end of this altruism.

The second article is a technical presentation of the research itself, which was the work of Jung-Kyoo Choi and Samuel Bowles:

The Coevolution of Parochial Altruism and War

Altruism—benefiting fellow group members at a cost to oneself—and parochialism—hostility toward individuals not of one's own ethnic, racial, or other group—are common human behaviors. The intersection of the two—which we term "parochial altruism"—is puzzling from an evolutionary perspective because altruistic or parochial behavior reduces one's payoffs by comparison to what one would gain by eschewing these behaviors. But parochial altruism could have evolved if parochialism promoted intergroup hostilities and the combination of altruism and parochialism contributed to success in these conflicts. Our game-theoretic analysis and agent-based simulations show that under conditions likely to have been experienced by late Pleistocene and early Holocene humans, neither parochialism nor altruism would have been viable singly, but by promoting group conflict, they could have evolved jointly.

Unfortunately, both articles require a subscription for access.

[T]here appears to have been almost no reporting on this research in the usual places that report on scientific research for a general audience. [T]he Santa Fe Institute, with which one of the researchers (Bowles) is associated, did put out this press release:

The coevolution of parochial altruism and war

In "The Coevolution of Parochial Altruism and War" appearing in the October 26 issue of Science, SFI researcher Samuel Bowles and colleague Jung-Kyoo Choi of Kyungpook National University in South Korea suggest that the altruistic and warlike aspects of human nature may have a common origin.

Altruism – benefiting fellow group members at a cost to oneself – and parochialism – hostility toward individuals not of one's own ethnic, racial, or other group – are common to human nature, but we don't immediately think of them as working together hand in hand. In fact the unexpected combination of these two behaviors may have enabled the survival of each trait according to Bowles and Choi.

They show that the two behaviors – which they term "parochial altruism" – may have in fact coevolved. On the face of it joining parochialism to altruism is puzzling from an evolutionary perspective because both behaviors reduce one's payoffs by comparison to what one would gain by avoiding them. Aggression consumes resources and risks death; altruism, particularly toward those with whom we have no direct relationship, has the effect of helping other genes advance at our expense. But parochial altruism could have evolved if parochialism promoted intergroup hostilities and the combination of altruism and parochialism contributed to the success of these conflicts.

Using game theoretic analysis and agent-based simulations Bowles and Choi show that under conditions likely to have been experienced by late Pleistocene and early Holocene humans neither parochialsim nor altruism would have been viable singly, but by promoting group conflict, they could have evolved jointly.

"But even if a parochial form of altruism may be our legacy," said Bowles, "it need not be our fate." He pointed to the many examples of contemporary altruism extending beyond group boundaries, and the fact that hostility toward outsiders is often redirected or eliminated entirely in a matter of years.

Now, none of this actually mentions religion. Choi and Bowles don't discuss it. So where does religion come into it? We'll get to that shortly. But first, let's review a bit about how altruism and cooperation in human cultures are thought to have evolved.

At first, it could seem that altruism and cooperation are unlikely to have evolved in humans at all, because they seem to be traits of an individual that are of more benefit to others than to the individual who happens to possess them.

However, there is a long history of evolutionary studies that have suggested how tendencies toward altruism and cooperation could have evolved in human groups. For example, starting in 1964 William D. Hamilton argued that altruism toward blood relatives helped to favor shared genes that fostered such altruism. This was termed "kin altruism".

Additional scientific consideration of the evolution of morality, altruism, and cooperation took off in the 1970s, in the work of people like Robert Trivers and Robert Axelrod. Using game theoretic arguments and simulations they showed how another type of altruism – "reciprocal altruism" – could arise in populations where individuals interacted frequently and could learn which others had earned a reputation for dependability in their dealings with other group members.

Many, many others have written on the subject since then, such as Edward O. Wilson (e. g. Consilience, published in 1998), and Steven Pinker (How the Mind Works, published in 1997). A very good history of the subject up until 1996 can be found in Matt Ridley's The Origins of Virtue.

On the other hand, in spite of arguments advanced showing the benefits to individuals of practicing altruism within a single tribe or cultural group, the fact remains that separate, unrelated groups could easily come into conflict over access to resources (e. g. water, game, other food sources, etc.), especially in times of scarcity due to overpopulation, unfavorable climate, etc. The result would be warfare.

Many people have also studied how evolutionary tendencies have contributed to aggression and warlike behavior between competing human groups. It seems that separate groups that have relatively low genetic similarity to each other and must compete for scarce resources have a notable tendency to come into conflict with each other, and to solve their problems of overpopulation or resource scarcity by killing as many members of the other group as possible. A good exposition of such ideas can be found in this article by Keith Henson: Evolutionary Psychology, Memes and the Origin of War.

It seems very reasonable to see such considerations as the source of the very human tendency to exhibit distrust and even hostility towards other humans who are noticeably "different", especially in physical characteristics, but also when there are simply cultural differences in taste, belief systems, etc.

Furthermore, when conflict between groups does occur and takes the form of open warfare, there is a distinct advantage for groups that have a high percentage of individuals who behave altruistically and cooperatively with each other. If you accept the (somewhat controversial) notion of evolutionary "group selection", this fact provides yet another evolutionary argument for the development of a third type of altruism – parochial altruism – within groups – because groups with the higher percentage of members who cooperate with each other will tend to prevail.

However, there is another side to this story. Individuals will not entirely lose a tendency to gain personal advantage through selfish behavior (such as hoarding food). Altruism can be disadvantageous for an individual if it goes too far, so there is some evolutionary pressure against it also. In an environment where scarcity of resources is not a large problem, individuals can serve their own interests by being open to interaction with members of other groups – especially for commerce and trading of "excess" goods. Individuals who are selfishly willing to trade their goods with members of other groups for the best exchange they can achieve will tend to do better for themselves since they are willing to "sell" to the highest bidder, regardless of group membership.

This, then, is the setting on which Choi and Bowles based their simulation. They considered two kinds of traits an individual could have. One related to altruism (A) vs. selfishness (N, for "not altruistic"). The other related to tolerance (T) vs. hostility (P, for "parochial") towards member of other groups. Any given individual could have one of four possible combinations (AT, AP, NT, NP). They started with groups having members with differing proportions of each possible combination.

Absent intergroup conflict, NT individuals (the most tolerant but selfish) tend to be most successful, and AP the least successful. But when intergroup conflicts occur, groups with the most AP types do better than groups with the most NT types. The simulations proceeded over thousands of generations, and a variety of parameters, all believed to be consistent with what is known about late Pleistocene hunter-gatherer human tribes, were tested.

The net result was that groups with many NT or AP individuals can both be successful, depending on how much warfare occurs (which depends on environmental conditions). But in most cases, groups with high proportions of NP or AT individuals lose out under any conditions. So one conclusion is that in order to have a lot of altruism within a group, you have to expect a lot of parochial intergroup hostility. Conversely, in order to have groups with a lot of tolerance towards other groups, you should expect less altruism and cooperation within the group. Choi and Bowles maintain that the same results tend to arise from a wide variety of different initial conditions.

True, this is "only" a simulation study. And it rests on the assumption that altruism and parochialism (or their opposites) are heritable traits (which alternatively might be transmitted culturally rather than genetically). But it seems to give results that accord well with what we know of human history. And that's where religion enters the picture. (Choi and Bowles do not discuss religion, so what follows is based on their findings, but also the contributions of others.)

In evolutionary terms, why is it that religion is so widespread in human societies? There are a variety of plausible explanations. One is that religion provides the rationale for moral and ethical principles that promote intergroup cooperation and altruism. The argument made by supporters of this idea – such as David Sloan Wilson in his book Darwin's Cathedral: Evolution, Religion, and the Nature of Society – is that societies and cultures with strong religion-based ethical and moral principles have a competitive advantage over other groups.

However, what the Choi-Bowles simulation suggests is that this advantage is realized only when groups often engage in conflict and war. For otherwise, there is an advantage for groups with lots of tolerance towards other groups, and lots of free-traders working for their own self-interest.

So, ironically, religion may have developed as a result of intergroup warfare, as a social artifact that helps justify intragroup altruism that actually was selected for because of the warfare. And at the same time, religion would also incorporate a justification for the intergroup hostility and aggression that arose from the same evolutionary process.

In other words, evolutionary pressures tend to bring about an association of religion and warfare. Note that this is not saying religion "causes" war. Indeed, evolutionary theory suggests that overpopulation and resource limits usually tend to be what "causes" war. But when such conditions prevail, it isn't too surprising to find a close association between religion and war. Just recall the slogan some religious believers are so fond of: "There are no atheists in foxholes." (In other words, most of the cannon fodder found in foxholes and military cemeteries is (or was) religious believers.)

Of course, most religions aren't pro-war full time. Many religious believers oppose war because of their faith. Nevertheless, most religions have their holy warriors, such as Mujahideen and Crusaders. (Military equipment of predominantly Christian nations is sometimes named a Crusader.) Most religions have their own versions of Onward Christian Soldiers. And most religions celebrate war in other ways.

But is there scientific evidence of a relation between religion and war? Yes. Consider this:

When God Sanctions Violence, Believers Act More Aggressively

Reading violent scriptures increases aggressive behavior, especially among believers, a new study finds. The study by University of Michigan social psychologist Brad Bushman and colleagues helps to illuminate one of the ways that violence and behavior are linked.

"To justify their actions, violent people often claim that God has sanctioned their behavior," said Bushman, faculty associate at the U-M Institute for Social Research and lead author of the article published in the March 2007 issue of Psychological Science. "Christian extremists, Jewish reactionaries and Islamic fundamentalists all can cite scriptures that seem to encourage or at least support aggression against unbelievers."

To be sure, this is hardly a new observation. Mark Twain, as well as many others before him, had already nailed it.
-Hacked & Jacked Charles Daney at Science and Reason


theBhc said...

Indeed. I think what we have been witnessing in our current epoch is a phenomenon that has roughly occurred throughout the history of empire; not all wars, certainly, but key ones.

A push for resource capture (material gain), vis à vis imperial expansion, has often been portrayed as battling mindless savages. Once this narrative is cemented, religiosity is quickly summoned to justify the aggression as an act of salvation. And once this sets in, the initial pursuit of material good, while obvious, becomes marginalized and downplayed by the righteousness of the cause of civilization, democratization, or whatever the current rhetorical flourish of the day happens to be. And, as we have seen, the religious extremists, who always leap quickly to the cause when presented a chance to prove the superiority of their religion, ignore the core reason for the war. This permeates public dialogue rather quickly. Before too long, no one can remember or admit that there actually is quite a lot of oil in Iraq, but, rather, worry about how badly the democratic experiment is going. Which, of course, demands continued effort until things improve. Concurrently, zealots leap to volunteer their saving graces, join the army, permeate the Pentagon and truly do believe that a religious war is underway. Our media, of course, are too embarrassed to report much of any of this.

Meanwhile, the oil companies move in and get the go-juice flowing. This is happening today, even as the political classes and corporate media express dismay at the dismal situation, while the zealots merrily march into Iraq with fervent dreams of religious conversion not far from their sweaty brows.

Meatball One said...

How ever did you land your gig at NASA? ;)

theBhc said...

I got in before Bush was around and, despite the current version of the NSA, apparently manage to keep a low profile. I think...

Anonymous said...

Excellent post. Goes well with this article from Sunday's SD Union Tribune. Fascinating atheist bashing. Athesim bad for national security?

Meatball One said...

Hi Isaac. (be ye the testy Isaac or be ye another?)

A person face to face with a lion is not put at ease by the conviction that he is a rabbit.” Wishful thinking of this sort would quickly have become extinct as its practitioners froze or were eaten.

The above statement/conjecture is completely and utterly false. Suffice it to say, it ignores all significant research and considered scientific thought into this area. And...the author draws conclusions so studiously one dimensional so as to come off in my books as a demagogue - as opposed to being a man of deep consideration and any meritable letters.

Country By Country
My response is:
The continent of Africa has the lowest number of bathtubs per capita of all continents (save perhaps Antarctica.) Africa has the most dark colored people per capita of any other continent. Somebody dare draw deep causal conclusions from this? D'Souza seems a guy who would dare.

When I want to read an insightful book on the magic growth and staying power of religion, I recommend Rodney Stark's Growth of Christianity. It helped me better understand the growth of Hamas and Hizbollah without resorting to speculation of Allah brain modules or terror genes.

"[He]introduce[s] historians and biblical scholars to real social science, including formal rational choice theory, theories of the firm, the role of social networks and interpersonal attachments in conversion, dynamic population models, social epidemiology, and models of religious economies"


"The idea that Christianity started as a clandestine movement among the poor is a widely accepted notion. Yet it is one of many myths that must be discarded if we are to understand just how a tiny messianic movement on the edge of the Roman Empire became the dominant faith of Western civilization. In a fast-paced, highly readable book that addresses beliefs as well as historical facts, Rodney Stark brings a sociologist's perspective to bear on the puzzle behind the success of early Christianity. He comes equipped not only with the logic and methods of social science but also with insights gathered firsthand into why people convert and how new religious groups recruit members. He digs deep into the historical evidence on many issues--such as the social background of converts, the mission to the Jews, the status of women in the church, the role of martyrdom--to provide a vivid and unconventional account of early Christianity.

The author plots the most plausible curve of Christian growth from the year 40 to 300. By the time of Constantine, Christianity had become a considerable force, with growth patterns very similar to those of modern-day successful religious movements. An unusual number of Christian converts, for example, came from the educated, cosmopolitan classes. Because it offered a new perspective on familiar concepts and was not linked to ethnicity, Christianity had a large following among persons seeking to assimilate into the dominant culture, mainly Hellenized Jews. The oversupply of women in Christian communities--due partly to the respect and protection they received--led to intermarriages with pagans, hence more conversions, and to a high fertility rate. Stark points out, too, the role played by selflessness and faith. Amidst the epidemics, fires, and other disasters that beleaguered Greco-Roman cities, Christian communities were a stronghold of mutual aid, which resulted in a survival rate far greater than that of the pagans. In the meantime, voluntary martyrdom, especially a generation after the death of Christ, reinforced the commitment of the Christian rank and file. What Stark ultimately offers is a multifaceted portrait of early Christianity, one that appeals to practical reasoning, historical curiosity, and personal reflection."
-Princeton Univ. Press

But I do admit, I enjoy the occasional bout of logical sinuousity - especially on Sundays. And Daddy D'Souza certainly delivers on that. Atheism bad for National Sec? I'd say many issues tabled at Haft of the Spear and Kent's and Mountain Runner speak better and more directly to problems upon us than what particular set of God archetypes we claim we adhere to.

Thanks Isaac, an interesting piece.

Anonymous said...

Aye, I be the 'testy' one...
And, yep, the 'modules and gene' bits cracked me up too. I was poking fun at the author with my question on national security, of course. Sadly, though, there are many that hold atheism to be somehow 'un-American'. I've read quite a few polls showing large majorities who'd never vote for an atheist - despite other qualifications and 'issues agreement'. I absolutely agree with you regarding the 'worth' this question should be assigned. (NONE, really) You're also right in pointing out laughable understandings of causation...
gotta run...

Meatball One said...

An honor, O ye testy one.

Glad you r indeed the very wise child I assumed you were - and I the cretin for nervously fretting that I perhaps be a steppin' on the toes of a treasured One.

Back to the grind, Christian soldier.

Adrian said...

Great post.

I've recently been reading some stuff on religion and altruism by Larry Iannacone at George Mason University - he approaches it from an economics perspective. Interesting stuff.

Meatball One said...

Thanks Adrian.

I humped it to Amazon to pick up a fist full of books on the topic religionomics. It should make for joyous Xmas reading.

The following link to some of his pdf'd publications should tide me over until my order catches up with me:

Adrian said...

I just put up a post that I think is related to this one:

I use a lot of Iannaccone's work.

Meatball One said...

Thanks, Adrian. Appreciated.