Our moral origins story begins 8 million years ago, plus or minus, when the lineage of the Common-Ancestor figure that Richard Wrangham identified for us was, as we’ve seen in Figure 1, splitting in two. At that branching point one of the two new lineages led to today’s gorillas, and to judge from what these apes do in the wild, this gorilla-based lineage either developed or retained a basically vegetarian approach to eating, along with a lack of territorial defense of natural resources and a haremic social structure. This will not concern us here, for it’s our more recent direct predecessor, Ancestral Pan, that we’re interested in because of its more developed talent for social control.
It’s very likely that Ancestral Pan continued all of the CA behaviors we’ve met with. To know with a high degree of probability what else this more recent ancestor was doing behaviorally, all that’s needed is to look for major patterns of behavior that are present unanimously in bonobos, chimpanzees, and humans—but not in gorillas. Again, the evolutionary principle of parsimony applies in reconstructing the behaviors of this ancestor,1 and, again, it will be useful to keep the analysis as conservative as possible since we are working with a small clade of only three species here. For that reason I will be looking for the least common denominator, wherever unanimity exists, and projecting only it into the past.
Thus, it will be Ancestral Pan who is the original inhabitant of our Natural Garden, while eventually we will have to include archaic Homo sapiens as well. For Ancestral Pan, the existence of natural-resource defense was significant.2 This became humanly important because territoriality and warfare pose such a profound practical problem for our own species.3 From the standpoint of evolutionary biology, such conflict between groups might also have contributed to moral evolution—if the group selection Darwin spoke of was activated sufficiently to have significant effects.4 But to start with, we must ask exactly how “territorial” and xenophobic the three extant descendants of Ancestral Pan are, respectively, and then look for the least common denominator.
Wild chimpanzee communities predictably stalk and kill their neighbors, and they may eventually wipe out an entire group and take over its resources.5 LPA human foragers, although often fairly peaceful, sometimes have intensive warfare that also rises to the level of genocide.6 However, bonobos’ territoriality is a far paler version of what chimpanzees and humans do, even though a similar basic pattern is readily discernible.7 When sizable foraging parties from neighboring communities meet near the edges of their territories, the xenophobic males are prone to vocalize hostilely with the smaller party withdrawing, and in one instance an injured bonobo male was observed afterward,8 so apparently the bonobos’ intergroup antagonism is not limited entirely to bluffing. On the other hand, some bonobo groups are reported to join up together amicably.9
With bonobos as the least common denominator, this means that Ancestral Pan’s territorial tendencies were setting up groups to actively dislike their socially distant neighbors, with at least some possibility of limited physical conflict. Conservatively, with this least common denominator Ancestral Pan, though xenophobic, was not a serious warrior.
It seems likely that contemporary very inconsistent LPA forager warfare levels may not be representative for frequent junctures in the Late Pleistocene, when our predecessors were facing dire scarcity due to climate change and group competition was likely to have been seriously exacerbated.10 One of the remarkable things about xenophobic tendencies in contemporary hunter-gatherers, and for that matter in all humans, is that our moral codes apply fully only within the group, be it a language group, a nonliterate population that shares the same piece of real estate or the same ethnic identity, or a nation.11 There seems to be a special, pejorative moral “discount” applied to cultural strangers—who often are not even considered to be fully human and therefore may be killed with little compunction.12
This moral downgrading of out-groupers generalizes beyond warfare between groups of coresident armed males, for today it can feed not only into genocide against the helpless, but also into terrorism that targets civilians. More generally, standard military ideologies make the “necessary” killing of civilian enemies palatable, even if they aren’t being used as human shields. “Regrettable, but acceptable” seems to define the collateral damage situation unless inflicting civilian casualties becomes a deliberate instrument of national policy, as with indiscriminant World War II bombing of cities like Nanking, London, Dresden, and Tokyo, with enormous and deliberate civilian losses, or as with the American attacks on Hiroshima and Nagasaki, which may have destroyed military targets but also killed similar numbers of civilians.
The underlying raw xenophobia can be traced directly back to Ancestral Pan. However, once culturally modern humans began to “moralize” their fear of or contempt for strangers, this gave us ethnocentrism.13 This culturally refined motivating force helps to support intensive conventional warfare and conquest, along with genocide as a particularly destructive type of warfare. Ethnocentrism, with its moral condescension factor, obviously has been important in establishing the sometimes quite deadly warfare patterns that some hunter-gatherers engage in today, but it may be difficult to estimate exactly how far back this violent, morally based type of cultural behavior reaches, how widespread it might have been in the Late Pleistocene at times when climates were more favorable,14 and, at the bottom line, to what degree it could have boosted Pleistocene group selection that favored the evolution of altruism.15
I must emphasize that the Pleistocene was different, even though conditions that would have spurred warfare were not constant. In that epoch, climate fluctuations could have led to recurrent situations of population growth and then, with dwindling resources, crowding, and serious political competition. If small groups were annihilating each other at sufficiently high rates, a Darwinian group selection scenario that favored groups with greater numbers of morally upright, cooperative altruists, including men acting as warriors, could conceivably have been in play quite significantly.16
Here, however, we’ll be concerned with what could have been a very powerful type of social selection, one that over evolutionary time could have been far more consistent in its effects than group selection if the latter were driven by warfare spurred by cyclical climatic downturns. This means that as far as moral evolution is concerned, we’ll be much more interested in what happens within groups, than between groups. In that context, I’ll be constructing a series of tentative and sometimes partly competing hypotheses about how human evolution, with major help from social selection, could have taken a turn in the direction of morality.
As I’ve said, the CA cannot be designated a hunter because gorillas don’t hunt. In contrast, Ancestral Pan was actively hunting—and sharing—some occasional small-game meat, and presently we’ll be learning about some finer details from bonobos and chimpanzees that underlie this ancestral assumption. Since then, at some point weapons-bearing humans began to regularly and actively scavenge, hunt and share the carcasses of animals larger than themselves; we’ve been doing this for at least hundreds of thousands of years, and as recently as 15,000 years ago human foragers, certainly the great majority, lived in mobile bands whose males hunted large mammals enthusiastically and often.
It’s possible that sometimes females were involved in this prehistoric hunting as well, for today there are a small handful of LPA bands that exhibit some female hunting,17 and both chimpanzee females and in particular bonobo females are known to hunt actively. There surely were Pleistocene junctures when human populations were being badly decimated by cold or drought and consequently some bands were becoming too small to be efficient at hunting,18 and at such times gaining extra hunters could have been useful as a way of increasing kill rates and reducing unwanted peaks and valleys in meat consumption. Thus, female hunters might have added to the general social flexibility that enabled Pleistocene humans to cope with a wide array of sometimes very sudden and often stressful environmental challenges.
LPA humans hunt large game as a dedicated activity that involves sophisticated systems of sharing. Chimpanzees and bonobos hunt casually and rather rarely, and in the absence of projectile weapons they go after smallish game.19 Bonobos hunt even less than chimpanzees, and they tend to do so as individuals, whereas sometimes chimpanzee males seem to be quite collectively oriented in their pursuit of attractive fresh meat.20 Both species appear to savor the fatty brains when it’s time to eat and share, and at Gombe what I found fascinating was the limited way that up to a dozen or more excited apes shared these carcasses; chimpanzees and bonobos have similar modes of doing this. Normally, a higher-ranking individual who captured the carcass firmly possesses the meat afterward and takes a lion’s portion, sharing with some of those who approach and beg for shares—but definitely not with others.
I’ll never forget a chimpanzee hunt I witnessed my first year at Gombe, when a foraging party with numerous adult and adolescent males aggressively captured four colobus monkeys in less than half an hour and began eating them. As a novice fieldworker, I asked Jane Goodall afterward why the alpha male, Goblin, had stayed on the ground throughout the hunt instead of climbing into the trees and participating. With the benefit of over twenty years of field experience, Jane told me that Goblin was waiting for someone else to make a kill so that he could selfishly confiscate it, and her interpretation made a perfect fit with what I had described that afternoon in my field notes. With so many kills being made, the alpha male knew he had a sure feast in his near future, so this habitual bully conserved his energy and let an adolescent male catch his meat.
It’s clear enough that meat is a prized food, for apes that are not given a share seldom leave the scene. They steadfastly bide their time hoping somehow to get some meat, and often enough these unsuccessful chimpanzee beggars become highly frustrated and prone to quarrel among themselves. In both bonobos and chimpanzees, the impression is one of gluttonously selfish possession, combined with rampant cronyism when it comes to limited sharing of this most precious of all foods. The overall sharing process seems to be shaped both by individual political power and by personal alliances.
Biologist Nicholas Blurton-Jones sees chimpanzees’ meat-sharing as a kind of “tolerated theft.”21 This means that it’s all about power, and the meat possessor isn’t really being generous at all. Rather, he or she realizes that the other hungry apes could fight to take away the carcass, so it’s best to share it with them—and thereby preempt their strike. However, in free-ranging chimpanzees I know of no record of a gang attack in which a stingy meat possessor was physically assaulted and dispossessed, even though often enough up to half or more of the apes present are being given no meat.
I have copublished a somewhat different theory, which comes from my having watched a fair number of hunts in the wild over a six-year research period, with eighteen months spent actively in the field.22 Jessica Flack and I have suggested that the possessors usually share meat with just enough partners to gain the allies needed to firmly control the carcass, but not with many others who are anxiously signaling their desire for meat as they jockey for a better position in the begging line. Thus, rather than passively “tolerating theft,” the meat-possessor, using his or her initial control of the carcass, is in fact quickly and actively buying a few allies—latent allies—who will help to balance power against the hungry nonrecipients. More generally, these allies are likely to serve as friendly political partners or as reciprocators in future hunts or sometimes as breeding partners.
Compared to tolerated theft, for chimpanzees in the wild the inferred political and emotional dynamics become rather different if we consider this balancing of power with socially bonded others.23 I believe these dynamics may hold also for the less-well-studied bonobos, for Pan paniscus follows a similar pattern of sharing with a favored few and excluding others, again without fights breaking out between the possessor and the excluded. This “alliancing” theory is congruent with the fact that at other chimpanzee field sites there is further evidence of political alliances being actively involved in meat-sharing. For instance, at the Kibale field site in Uganda, certain pairs of males enter into productive meat partnerships; if one of them controls some meat, he will share with the other—as long as such reciprocation is being continued over time.24 And at Tai Forest in West Africa, where cooperative hunting seems to be in play more than elsewhere, individuals who have allied to cooperate in killing a prey also cooperate in eating the meat, while nonparticipants are excluded.25
The distinction between tolerated theft and an alliancing approach to meat control is rather subtle, but it’s important for this evolutionary analysis because we’ll be focusing on sympathetic feelings that are involved in social bonding. Tolerated theft interpretations make possible the assumption that what appears to be “sharing” actually involves no element of perspective taking or generosity, but rather just a fearful concession to the potential power of others. In contrast, with an alliancing interpretation it makes sense that sharing with favored allies would involve some social bonding and hence, quite possibly, some ape version of sympathetic generosity that combines with political expediency.26
There’s no reason, then, that the two theories couldn’t be combined, for we might surmise that the possibility of a gang attack leads a meat possessor to share with just enough bonded allies to discourage active incursions by those who are excluded. But the bottom line is that the meat possessor is, in effect, using some of the meat to purchase allies, which implies positive social feelings as well as fear of an attack. This pattern of meat “bartering” sometimes can apply to securing sexual favors from females as well, as a special bonus,27 and again an emotional kind of bonding seems likely.
When humans share large game, aside from certain tensions and sometimes some superficial squabbling, there’s obvious community joy in participation—because meat is so deeply appreciated, because no one is left out, and because eating meat together is a splendid way to socialize commensally. In observing wild chimpanzees, I’ve always noticed that the sharing process itself appears to be extremely tense and hostile among the competing beggars—but at the same time both tense and amicable between the sharing partners and sometimes downright friendly. (This is only an impression.)
Field reports suggest that the same could hold true for bonobos, who also share very sizable fat-and-protein-rich fruit items as adults,28 and it’s worth noting that in both ape species, as with humans, mothers regularly share food with begging infants and—again—that such accommodation should involve substantial positive feelings. This adult meat-sharing likely involves some kind of a behavioral extension of strongly selected maternal generosity,29 but ultimately, at the level of genes, the frequent sharing with nonkin must be explained through benefits of political alliancing or through some other compensatory mechanism that repays the loss of meat when it is less than abundant.
Of course, even when ape mothers share with their infants, it’s difficult to demonstrate that sympathetic feelings are at work, and such interpretations are still more difficult with adults. But if we set aside the question of motives, it’s clear that Ancestral Pan’s rather limited sharing patterns—based on what bonobos do at their rather rare meat feasts as a least common denominator—provided an important preadaptation in terms of behavioral potential. Thus, when archaic humans finally decided to turn from hunting small game (and probably aggressively scavenging a large carcass once in a while) to actively hunting sizable ungulates as a major and regular part of their subsistence, they already had something rather significant to work with in the meat-sharing department—even though the sharing pattern would have been involved with dominant possession and the favoring of cronies and therefore would have been quite lopsided.
In The Hunting Apes, primatologist Craig Stanford takes the position that, although cooperative hunting was an important development in human evolution, sharing the meat was even more important. In today’s bands hunting and sharing are greatly elaborated by cultural practices and symbols,30 which means that in maintaining customary systems of meat-sharing, the political power moves tend to be far more subtle than with Ancestral Pan. In this context I think that even though some foragers habitually argue about whether ongoing meat distributions are by the rules and fair, or grouse about their shares afterward,31 underlying this cantankerousness are usually feelings of goodwill. These emotions help to enable the sociable process of equitably sharing a large carcass, for everyone will be sharing a food that is nutritionally useful to all—and is supremely delicious as well.
The existence of these positive feelings is attested to by dozens of rich ethnographic accounts of sharing and also by the fact that serious conflict, as opposed to squabbling, is all but absent from the scores of instances of meat-sharing I’ve covered so far in my extensive LPA hunter-gatherer survey. Some ambivalence is expectable, of course, because humans are so heavily given to egoism and nepotism. But even though people from different families may bicker a bit, and in some groups they may complain loudly to remind others of how the system’s supposed to work,32 I believe that even the habitual complainers appreciate the benefits of their sharing systems, are able to make them work quite efficiently in spite of a few rough edges, and, again, can take delight in eating their favorite food with others in the band.
That we became efficient, cooperative, equal-opportunity meat sharers was important to our overall evolutionary success, for this expanded our diet breadth and allowed us to exploit major new subsistence possibilities.33 At some level I believe that archaic Homo sapiens, with its relatively large social brain, must have understood something about the importance of hunting cooperatively and about the advantages of sharing meat among the entire band. Today, egalitarian hunter-gatherers definitely seem to appreciate the advantages of having a band with more hunters, for obviously this means that the big carcasses to share will come in more often and hence there will be fewer hiatuses when people simply have no major meat to eat.
I think they might understand several fairly obvious long-term advantages of equalized meat-sharing, precisely because evening out consumption of this prized food provides nutritional benefits that lead to everyone’s being more energetic and healthier, for people who live precariously close to nature are likely to have such insights. In any event, modern theories out of behavioral ecology reach exactly the same conclusions and show that these human patterns34 are very much like those appearing on a purely instinctual basis among pure social carnivores, such as wolves or lions.
All social carnivores face the same logistical problems. Not only do they have to hunt as groups in order to keep the sizable and difficult kills coming in at least fairly regularly, but they also have to share these large kills fairly even-handedly if their diet is to sustain an energetically demanding occupation like team hunting, which works best if all the members of the hunting team are decently nourished on a continuous basis.35 Dedicated social carnivores like wolves or lions are invariably hierarchical, and basically it is an evolved social structure that determines who gets how much meat. The simple fact that group members know when to dominate and when to submit prevents competitive conflict from getting out of hand, and with these pure meat eaters the challenge for natural selection has been to evolve mechanisms that ensure that some significant level of sharing takes place whenever meat is not very plentiful.
In the face of all this hierarchy, the sharing needs to be sufficient to adequately nourish the lower-ranking team members and also to ensure that the overall gains of group hunting are not lost in fighting over meat. The likely mechanism would be that selfish, aggressive, higher-ranking individuals are evolved at least to be tolerant when it comes to sharing a carcass with subordinates. Thus, even though the sharing may be far from equitable, the large carcasses they kill will be spread around better than with bonobos or chimpanzees with the much smaller animals they capture.
The technical name for this evening out of meat consumption is “variance reduction.”36 In humans alone, something really close to equalized meat intake is accomplished—but only with the assistance of symbols, cultural inventiveness, and the unusual capacity of our LPA groups to collectively control (or eliminate) powerful individuals who otherwise would dominate the meat scene. Because we deeply appreciate the benefits of sharing, and because we understand the politics involved, we can use various carrots and sticks to back up the relevant cultural institutions and customs once they’ve been invented. In this way hunter-gatherers see to it that their overall systems of sharing will generally work smoothly—that is, without frequent and costly serious conflict.37
Archaic types of Homo sapiens stuck around for almost half a million years, with a relatively static and, as far as we know, relatively unimaginative stone culture that nonetheless was up to the tough job of Pleistocene survival. These humans turned to the intensive hunting of large game only 250,000 years ago, and by 200,000 years ago they were becoming anatomically but not yet culturally modern, even though their technology was improving.
When these archaic humans took on large-game hunting, to reduce major fluctuations in their family-level meat consumption they were obliged to share carcasses as entire bands, rather than just as smaller social units—units that probably were based strongly on maternal, fraternal, and sororal kinship and possibly also on pair bonding by breeding partners and paternal kinship. The alternative, in the absence of long-term storage, was for the lucky hunter’s social subunit or “family” to have a short-lived selfish feast when he brought in a big carcass a few times a year, probably sharing some with a few cronies, and otherwise to endure very lengthy meat famines as far as sizable ungulates like antelope or zebra were concerned.
The set of hypotheses I shall be proposing involve earlier humans living in bands, and they involve male competition over scarce commodities like large-game meat and breeding opportunities with available females and also competition for power38 in its own right. But before I begin to put together a group of possible scenarios for moral origins, some additional background will be needed.
There are a big handful of early “hominid” species that may or may not have been directly in the human line—I say this even though when their discoverers publish in Science or Nature, they sometimes tend to imply, or even claim, that their particular species is definitely a human ancestor rather than merely some upright ape that went extinct as a side branch. All are bipedal in gait, their brains are about the size of present-day Pan, and generally for several million years they show no strong evidence of regular pursuit hunting. We may speculate that as descendants of Ancestral Pan, the well-known Australopithecines and their like at least were very likely to have hunted some small game, and with equal probability they were at least making some clever tools out of softer materials. However, if a given species was heading for extinction, it could have lost some of these ancestral traits.
It may have taken several million years for fashioning stone materials into tools to have been expressed robustly,39 but just after 2 MYA we do see an archaeologically known upright ape species that did some scavenging and possibly some active hunting. One of these terrestrial apes may or may not have been our direct predecessor, but their skeletons continued to look quite apelike aside from being bipedal, and their brain size was only somewhat larger. If the later, somewhat larger-brained species that Louis Leakey optimistically designated as Homo habilis was our direct ancestor,40 then it would seem that in our line we’ve had the use of manufactured stone tools for several million years now, and we’ve been using them for butchery for the same amount of time. Unfortunately, it seems possible that Leakey’s “humans” belonged to a highly dimorphic lineage that went extinct or even that more than one species were involved. Thus, some experts41 are reluctant to include habilis as a member of Homo.
The first fossil with a definite and undisputed claim to human ancestorhood is Homo erectus,42 for some time a contemporary of these later upright apes. Erectus appeared before 1.8 MYA and is far more reminiscent of us than any living ape or any prior fossil. Tall and slender but very strong, its body was built for long-distance walking or running far more than for tree climbing, and its skull held a brain far larger than that of any ape—even though it was only about half the size of our own. Within a few hundred thousand years, the African version of Homo erectus was making beautifully fashioned Acheulian axes, a stone tool industry that lasted with few changes for over 1 million years. And these early African humans were also hunting more and more as, after spreading into Eurasia as an extremely successful species, they evolved in Africa into the still-larger-brained archaic Homo sapiens we’ve been discussing. That larger-brained species, after staying around successfully for several hundred thousand years, eventually turned to the active hunting of large ungulates and soon thereafter evolved into modern humans.
Archaic Homo sapiens had quite large brains, indeed, and their bodies were made on the same lanky plan as Homo erectus but were still more modern. Toward the end of their evolutionary career, these archaics finally gave up on the very static Acheulian stone tool tradition that erectus had invented and began to manufacture implements that were more imaginative. But culturally modern they were not. For instance, they were not yet creating distinctive local cultures in short order by quickly elaborating their stone tool and other technologies in ways that were highly inventive, as today’s foragers do. Such cultural creativity, along with such things as self-adornment with seashells, the carving of phantasmagoric sculptures, cave painting, and the fashioning of musical instruments, was to come later with cultural modernity.43
As early as 400,000 BP, these archaic predecessors of ours were hunting with carefully fashioned wooden weapons.44 Remarkably, several spears probably belonging to them were interred in anaerobic soil in Germany and preserved to the present. They are nicely made and well balanced for throwing, just like Olympic javelins, and they may well have been used for killing groups of wild horses—which means that even then the people involved sometimes had some sizable packages of meat to divide up. However, we don’t know how often they were killing such meat, and the sparse archaeological evidence cannot support the idea that back then big game was a staple dietary item that they depended on regularly enough to require a new system of sharing.
By 250,000 BP, however, according to archaeologist Mary Stiner,45 the evidence for large-game hunting as a serious and routine pursuit of archaic humans becomes overwhelming. Our African ancestors’ subsistence continued to be heavily based on plant foods, but large animal carcasses were being relied upon as well, and animal flesh was no longer merely an occasional major treat. Actively pursued sizable ungulates like antelope were now a staple, and for the theoretical reasons given previously the acquisition and disposition of this important food had to be well integrated into a nomadic foraging lifestyle that previously, in all likelihood, had involved a primary dependency on staple plant foods, along with some small game, far more than on occasional large-game windfalls. That’s our general evolutionary backstory as far as subsistence is concerned. But with respect to politics within groups, there’s much more to say.
We’re particularly interested in subordinate coalitions and in how they became potent enough to all but neutralize the alpha role in a species that remained (and still remains) innately prone to form social hierarchies.46 At 8 MYA behavioral phylogenetics has told us with a substantial degree of probability that the CA had a largely unexpressed potential for subordinate coalitions to attack dominators who rubbed the majority of their immediate social community the wrong way. With gorillas as the least common denominator, such ancestral rebellions are conservatively judged to have been either merely potential or quite rare. However, at 6 MYA the same conservative methodology tells us that in all likelihood Ancestral Pan not infrequently attacked disliked dominators to reduce their power, with the possible outcome of wounding or, more rarely, death. This punitive type of social selection had at least the occasional effect of significantly disadvantaging the genes of those bully types who were attacked—even though in general domination surely continued to pay off handsomely in feeding and mating contexts.47
In suggesting that such social selection could have been lethal, I’m thinking about what we know for certain about the two Pan species and also about what seems very likely. As we’ve seen, humans use capital punishment widely, but only once has a non-scientist actually observed a counterdominant, group-inflicted death within a social community in today’s Pan. Primatologists in fact have described several cases of subordinate rebellions that certainly seem to have resulted in death—but technically a scientifically conservative ethologist could count them only as gang attacks leading to “disappearances.”
At the Mahale field site in Tanzania, chimpanzee Ntologi, an aggressive former alpha male, was gang-attacked by members of his own community and was never seen again by the Japanese fieldworkers there.48 As chimpanzee males can’t safely immigrate into hostile neighboring groups, he likely died. Goblin, the alpha-male chimpanzee at Gombe when I was there, was gang-attacked so fiercely that he fled into exile, subsisting for months in peripheral areas where—if he’d been caught by an enemy patrol—he’d have been killed right on the spot.49 Goblin in fact survived to live for many years as a socially accepted male in the group that had rejected him, but Ntologi was never seen again. It’s possible that he died of his wounds or that he was caught by enemies; he might even have died in exile of natural causes, but in any event he was definitely put at lethal risk by being exiled, as was Goblin.
Similarly, a sizable group of wild bonobo females in Zaire attacked a male bully, biting severely at his digits, and after moving away with many serious wounds, he was never seen again.50 He may have died of his wounds, but it’s at least conceivable that he might have immigrated to another group, even though bonobo males very often show definite signs of hostility when two communities meet by chance.51 Thus, he too can be counted as a “probable” with respect to dying of his wounds. In both species, then, it’s likely that even in the absence of manufactured lethal weapons, serious gang attacks can lead to mortality and hence a major loss of fitness. And we already know about the use of capital punishment by human foragers.
Accordingly, we may assume that throughout human prehistory well-armed subordinate coalitions, if properly motivated, could gang-attack high-ranking group members and do them serious or lethal damage. We may also assume that when large-game hunting was added to the human subsistence pattern, this provided a new social stimulus that favored a definitive solution for the alpha-male problem—in case it hadn’t been resolved previously.
In scientific research we sort out theories according to their “provability,”52 their predictive power, their general plausibility, and, more generally, how satisfactory the explanations are that they generate. In attempting to build an explanation of moral origins, the best I will be able to do is to provide working hypotheses—some of which some scholars may see as being merely glorified hunches, while others may see them as highly worthwhile leads for future research.
The theory I’ll be developing in this chapter is that the advent of our moral conscience came through the agency of a special type of natural selection, namely, social selection as this has been discussed in Chapter 3 and elsewhere. Basically, this involved the effects of human preferences, either in choosing others in useful partnerships or in coming down hard on disliked deviants.
Specifically, the first part of the moral origins argument is that in our human past when group punishment became severe and frequent, this significantly affected the human gene pool because punishment reduced the fitness of deviants. The second and less obvious part of the argument is that as the severity and cost of such punishment escalated, this created a selection pressure that favored individuals with better personal self-control. The instrument of this better social navigation and more effective self-restraint was the evolving conscience, and in trying to make this theory as specific as possible—and to try to place conscience origins in time—I will have to create some rather speculative arguments. These will concern how and why punishment in earlier human groups could have escalated to become a major force that shaped gene pools.
In the natural Garden of Eden scenario we are going to consider, I shall propose that when humans embarked on a new kind of subsistence pattern that was based heavily on hunting, this could have raised predictable social challenges, challenges that could have been met only by groups cracking down on individuals whose behavior threatened the efficient sharing of a very special type of food. The only way to test a specific theory like this one is in terms of its relative plausibility,53 and fortunately there are some key facts that can be marshaled to give it support.
The main obstacle to setting up an equitable sharing system for a band of five to six hunters and fifteen to thirty people in all would have been an ancestral type of alpha male, who predictably would act as a dominator prone to appropriate the meat of others and favor his kin and cronies; this prehistoric alpha problem was identified several decades ago by archaeologist Robert Whallon.54 There’s still a great deal of the alpha dominator in our genetic nature today,55 and, if personally uninhibited and socially unrestrained, this would quickly translate into gross inequities in the meat consumption of today’s hunter-gatherers. It also would translate into tendencies to turn meat into political power because the possessors would likely be using their extra meat to favor kin and political allies and mating partners, just as took place ancestrally. Thus, whenever earlier humans went up against whatever preexisting ancestral type of alpha-male system was in place, they would have been playing a zero-sum game as they ganged up to do battle with dominant individuals who loved meat and were used to controlling and hogging it.
In this competitive game there was a great deal at stake for the well-fed dominants, whose nutrition previously had been coming out so far ahead, just as there were high stakes for the previously undernourished subordinates who increasingly would have been motivated to rebel actively as large packages of meat became more important to their well-being. Conflicts most likely would have been inevitable, as a newly equalized, culturally based sharing system was being put in place. And ultimately it surely had to be kept in place by the threat of force, just as takes place in the egalitarian present.
Ancestral Pan’s society was hierarchical, with alpha males. We may be quite sure about this. We may also be quite certain that by 45,000 BP humans had created decisively egalitarian orders—something that bonobos and chimpanzees obviously have not managed to carry nearly as far because, in spite of their subordinate rebellions, they still have alpha males, and in the case of bonobos, alpha females. Somehow, at some point, we humans decisively got rid of our alpha males and became egalitarian. It’s logical that such a definitive step in the egalitarian direction was motivated by a rank-and-file envy over the perks of alpha bullies, which related to power, food, and sex. More basically, the issue was personal autonomy, and I’d suggest that Ancestral Pan had a strong distaste for being intimidated and bossed around.
For explaining how the human conscience originated, the initial scenario I’m developing provides what might be called a likely ecological key. The several hypotheses I’ll be dealing with here are necessarily tentative, but of course new archaeological findings—as well as new competing hypotheses—may provide ways of testing them further. Furthermore, future developments in behavioral genetics could eventually enhance such investigations. However, for now we must view them as working hypotheses that are difficult to test aside from assessing their plausibility in contrast to other theories of moral origins, which we’ll be meeting with in Chapter 12.
In its basics, the initial hypothesis isn’t very complicated. It posits that a quarter of a million years ago, when relatively large-brained archaic humans took on large-game hunting as a major and regular occupation,56 they would have needed to share large carcasses, and share them efficiently as described above, so that entire hunting teams could remain well nourished and vigorous. We’ve seen that if alpha-male behavior were flourishing, this would have been a serious obstacle to such sharing, and that the only possible solution to this problem—the only one that I can think of—was for subordinate coalitions to have taken care of this problem forcefully.
Ancestral Pan’s limited but significant subordinate rebellions provided the preadaptation, and this hypothesis assumes that archaic humans could have escalated such behavior to the point that, to definitively control their alpha problems, they would have developed some systematic type of collectivized and potentially lethal social control. The aim would have been to prevent high-ranking bullies from just naturally monopolizing large carcasses killed by band members, and thereby acting as free riders, when it was the undernourished others in the band who were doing much of the hard work in hunting.
As a result of this very likely conflict, those powerful individuals who were better able to restrain their potential aggressions would have had better reproductive success than those who didn’t—and got themselves killed. Thus, the evolution of more effective personal self-control could have been selected strongly. This can be taken as the beginning phase of moral origins, because it would have led to the internalization of rules and the development of a self-judgmental sense of right and wrong.
We may at least consider some further details. As better self-inhibition became individually adaptive, it could have applied not only to bullies but also to others whose antisocial behavior obviously threatened efficient meat-sharing, those disposed to act as meat-cheaters who wanted to hide carcasses they’d killed, or thieves who wanted to stealthily take the shares of others. When these three types of “deviants” started being punished by their groups, the result would have been that those who better inhibited themselves from taking such dangerous free rides were gaining greater fitness. It’s precisely because our consciences often can inhibit seriously deviant behavior, and save us from punishment, that this hypothesis could explain conscience origins.
That’s the first hypothesis. It holds that in theory social selection in the form of concerted group punishment might have begun rather abruptly as active large-game hunting phased in, because the collective punishment of intimidators could have been intensified wholly or mainly as a cultural development. Such a development required no further biological evolution, because in the form of subordinate rebellions substantial preadaptations were already in place 6 million years previously. However, there are several potential wild cards that could modify this hypothesis.
First, it’s possible that earlier on alpha-male systems had already been subject to some substantial attrition at the level of the genetic dispositions that support them, simply because we know that in all likelihood Ancestral Pan—and also its direct descendants in the human line—was so averse to being dominated. Long before the regular hunting of sizable ungulates began, these increasingly large-brained humans might have slowly become better able to use subordinate coalitions to reduce the power of resented alpha-male dominators, not only because ever since Ancestral Pan they had always strongly preferred personal autonomy over domination, but also, quite possibly, because subordinate males wanted a greater share of mating opportunities.
Thus, punishment sufficient to accomplish some evolution of better self-control could have begun much earlier. However, the basic moral origins hypothesis I’m developing here could stay the same, for when hunting arrived, more decisive group power moves still would have been needed to take out whichever would-be dominators were still impelled to act on their ability to intimidate—while favoring those with better self-control. Similar social selection would have applied to serious cheaters and thieves, who also threatened a reasonably equalized, nutritionally efficient apportionment of meat.
With this second scenario the evolution of egalitarianism could have begun quite gradually, through an interaction of genetic and cultural factors. We may speculate that the earliest likely major escalation of egalitarian behaviors would have been with Homo erectus, for this would have involved some complex political challenges, and this first really certain human had a significantly larger brain than its probable apelike predecessors. Would the sharing of sizable meat kills have been part of the picture? With this earlier human there was an archaeologically visible interest in very large game, but this may have been actively scavenged only once in a while, when opportunities arose.57 Otherwise, the exact role of meat in that early diet is more difficult to determine, aside from the fact that Ancestral Pan’s pattern of taking small game all but surely was continuing in the direct human line.58 If in fact some medium-sized large game also was being hunted actively and regularly by Homo erectus, then a systematic and aggressive approach to better equalized meat-sharing might have been invented as early as around 1.8 MYA. I say this because unlike very large mammals, such as elephants, game like antelope-sized ungulates do not provide a surfeit of meat. As a result, efficient sharing becomes useful.
It’s difficult to project such speculations further back in time, for it seems likely that the earlier terrestrial apes in the human line would have had more limited social brains, while overall the archaeological evidence is quite scarce. In this connection, the more ancient the field site, the more likely it becomes that fossilized bones of less enormous butchered prey might have decomposed to the point that cut marks made by human tools might not be discernible.
Such a very early meat-sharing hypothesis cannot be absolutely ruled out, but as we’ve seen the solid evidence we have today does point to 250,000 BP for the beginning of active and regular hunting of sizable but not enormous game. And even if for some reason antihierarchical subordinate coalitions had begun to significantly whittle away at alpha power as early as with Homo erectus, the later advent of intensive large-game hunting could have greatly accelerated this political process.
What we may say, with a high degree of certainty, is that Ancestral Pan was hierarchical—and that at some point along the way, and surely by 45,000 years ago when cultural modernity had phased in fully, humans had become decisively egalitarian. We can also say that this was because alpha types were being put down, or executed, if they failed to control themselves and restrain their own power moves. This takes place today, and it is difficult to imagine any other way that it could have been accomplished yesterday.
When large-game hunting did phase in, if it were to succeed—and if decisive egalitarianism were not already in place—some really severe sanctioning would have been necessary as the inadequately inhibited self-aggrandizing alphas—along with greedy thieves and cheaters—were attacked by forceful coalitions of group members who ganged up to control the meat as a highly valuable form of “community property.”59 It’s logical that merely doing the job halfway would have resulted in very high levels of conflict over meat, and that therefore, after 250,000 BP, the only viable course for efficient meat distribution would have been to suppress alpha behavior definitively.
This evolutionary hypothesis attempts to base a theory of moral origins in human behavioral ecology and also in an assessment of earlier humans’ social behavioral potential. It awaits the creation of plausible alternatives by other scholars—and further archaeological evidence—as the only likely means of scientific testing in the very near future. In a different sphere, it’s difficult to predict how long it will be before behavioral genetics may provide further key information that could be useful in making behavioral and chronological assessments.
At this point, we’re left with really three alternatives. One is that archaic humans had not progressed very far beyond ancestral behaviors in the matter of keeping down alphas and that large-game hunting led to radical political change and also to some severe initial conflict in putting down the poorly inhibited alphas. Another would be that before that, with earlier humans their coalitions would have partially reduced alpha power—in order to improve personal autonomy and probably also to increase the breeding opportunities of lower-ranking males—and that this would have made the transition to relying upon large game much easier. The third would be that decisive egalitarianism was already in place when such hunting began and that in fact this might actually have been a prerequisite for large-game hunting to succeed.
Further research findings will be needed if we are to choose scientifically among these three hypotheses, but all three of them deal with basic variables that are pertinent to the emergence of an evolutionary conscience. With respect to such conscience evolution, this could have been quite gradual or heavily punctuated, depending on the hypothesis and on how powerful social selection, in conjunction with group selection, would have been.
When Whallon pointed out that alpha hegemony would have interfered with the egalitarian sharing process that goes so strongly with hunting and gathering today,60 he did not present a hypothesis for how an equality-based political order could have supplanted the old hierarchical one. However, in Chapter 4 we looked rather carefully at contemporary egalitarian foragers and found one drastic answer—in the form of capital punishment. There we saw that quite often this serves as a means of eliminating free-riding problems connected with overly dominant behavior. Once serious hunting began, and large amounts of meat were arriving in camp on a sporadic basis, very likely meat thieves and meat-cheaters would have been lesser targets, while greedy alpha bullies would have received the brunt of serious social sanctioning, just as takes place today. I emphasize that more than half the executions visible in today’s LPA ethnographic record for fifty societies were likely to substantially improve the chances that everyone could share equitably in the distribution and eating of large carcasses, and as we’ve seen in Table I, among LPA foragers it was definitely the bullies, far more than the two sneakier types of deviant, who were singled out as the main targets.
When archaic humans began to hunt, let’s assume for a moment that they were not yet fully egalitarian. Because the necessarily forceful imposition of new, more effective meat-sharing customs on alphas who were used to getting their own way was likely to have been bloody, this would have driven up the rate of social selection in favor of better personal self-restraint. On the other hand, if subordinate rebellions had already become more frequent and more effective, and if the power positions of tyrannical alphas had already been partly undermined, an equitable and efficient sharing of meat would seem to have been easier to set in motion and, as I just suggested, the rate of social selection would have been more gradual.
To summarize here, we cannot rule out the possibility that earlier archaics might even have already become fully egalitarian before 250,000 BP, which could have paved the way for large-game hunting to flourish quickly and with far less conflict because efficiently equalized meat-sharing rules could have been so much easier to impose. In this case, conscience evolution and moral origins would have begun earlier, and social selection might have been motivated more in rank-and-file desires for more personal autonomy, or in rank-and-file males wanting more breeding opportunities, than in needs to widely share large-game carcasses. However, whenever it was that a serious reliance on large game began, this new development still could have raised the rates at which alphas were being gang-attacked, wounded, or killed by subordinates who wanted assured shares of a highly precious food that arrived so rarely and in such large packages. And this could have accelerated the rate of conscience evolution.
This theory is basically political in that I have tied this strong selection force closely to the advent of egalitarian social orders. These hypotheses provide a very large window during which punitive social selection could have operated to make us moral, and these social orders could have begun to develop at any time in the course of human evolution, really. However, for today’s definitive kind of egalitarianism to have flourished, it would have been necessary for human social and political intelligence to become powerful enough for subordinates to decisively curb the alphas in their bands.
It was when such punishment really took off that I think the older, ancestral, fear-based mechanisms of self-control could have been supplemented by newly evolved traits that added up to moral origins. These included more sophisticated perspective taking, the internalization of rules that made for more efficient adjustments of individuals to the perils of living in a group that was prepared to kill serious deviants, a sense of shame, moralistic judgment of oneself and others, and a special type of symbolic communication in the form of gossip.
This may seem a rather banal explanation for something as exalted as moral origins, but I offer it until a better theory comes along.
Presently, I will offer some archaeological evidence about butchering methodologies, which at least suggests that at 400,000 BP human foragers were not yet fully egalitarian. First, however, let’s look to the more recent past and return to the issue of capital punishment as an antihierarchical measure. In this connection, consider three examples of more recent Magdalenian cave art from Spain,61 which probably date back to the time when these culturally modern foragers were adjusting to the arrival of the Holocene Epoch, with its more stable climates. What we see in one is a cluster of ten male archers who seem to be rejoicing in something they have just done as they expressively wave their bows in the air. Lying on the ground some yards away is an inert human male figure who looks almost like a porcupine,62 with exactly ten arrows sticking in him. That’s all we know for sure, but some speculation is possible.
First, ten archers suggests a band of perhaps forty, which would be a bit larger than average today, but well within the central tendencies already discussed. Elsewhere in Spain, two similar depictions show three and six archers, respectively, so the overall average would be about six, which seems to be right at the average for contemporary foragers—even though with such a small sample size, this is merely suggestive. Second, with the killings done unanimously and at short range, this would appear to be an instance of execution within the band, rather than a very lopsided act of killing between bands. We can’t be sure, but the appearance of this event three times suggests that it could have been an execution scene similar to the “communal” one described by Richard Lee for the Bushmen, where a serial killer was “porcupined” by his group.63 We’ll meet with the vivid details in a later chapter.
This interpretation is bolstered if we reconsider the political dynamics of group executions and the two ways that present-day foragers see to it that the executioners, who are fulfilling an important public duty, are not themselves killed by the executed deviant’s angry relatives. Briefly for now, the main way is to delegate the bad guy’s close kinsman to kill him, which is clearly not the case here. More rarely, the entire group may act as one to take him out, which jibes perfectly with what’s seen in these cave depictions. Some further speculation is possible if we consider statistically the causes for capital punishment presented in Chapter 4 in Table I.
These three cave depictions might have shown the executions of fear-inspiring sorcerers or some other kind of bully, but we can only speculate about this. They might also have been prisoners of war, although this seems less likely. But what these depictions do tell us is that culturally modern humans were capable of killing someone they did not like, by acting in groups.
Capital punishment episodes are relevant to the selection of genes precisely because the fitness of those being punished is so seriously disadvantaged. However, as we’ve seen ethnographic underreporting makes it difficult to come up with any precise annual rates for capital punishment among today’s mobile foragers. What we do know, however, is that, whereas the overall homicide rates for today’s LPA hunting bands actually may equal the rates in dangerous cities like Los Angeles,64 only a small (but still significant) portion of these would be capital punishment because most killings simply grow out of one-shot conflicts over women. However, prehistorically when bands needed to hold their more determined alphas in check in order to share large game, capital punishment was likely a viable and sometimes necessary option in dealing with the harder cases, and this could have profoundly affected gene pools.
Here’s a further and socially important piece of evidence on earlier meat-sharing that supports the idea that definitive, egalitarian control of large-game carcasses could have arrived about a quarter of a million years ago, rather than much earlier. Mary Stiner and two Israeli archaeological colleagues65 carefully examined the cut marks on bones from a number of large carcasses butchered by earlier archaic humans in the Middle East, which at the time could be considered a geographic extension of Africa.66 They discerned very different patterns at 400,000 BP, when acquiring large game still seems to have been a side occupation, as compared with 200,000 BP, when active pursuit of hooved prey had already been a mainstay for 50,000 years. Those 400,000-year-old cut marks were chaotic and varied, as might be expected if several people had been doing the butchering from a variety of angles with different tools and using a variety of personal cutting styles. This earlier human pattern seems fairly consistent with the chimpanzee-bonobo meat-eating scene, which is replete with competitive political dynamics and generally involves several individuals working a carcass at the same time—even though one individual is clearly in control. With these Middle Paleolithic archaic humans, the sharp stone flakes used for butchering could have made it important to share without much conflict, for if serious quarrels arose over meat, unlike today’s two Pan species the butcherers already had quickly lethal weapons in their hands.
In contrast, at 200,000 BP the cut marks are those of a single individual assuming a single position to butcher the entire carcass. The potential implications are enormous, for this later pattern is quite reminiscent of what takes place with modern hunter-gatherers, where in effect the meat becomes a vigilant band’s common property, to be widely shared in a systematic, culturally routinized fashion that averts serious conflict.67 To avoid even tempting the more dominant individuals to make selfish inroads into this latter system, predictably the carcass is handed over to some “neutral” meat distributor who was uninvolved with the kill.68 This practice sees to it, by custom, that a successful hunter does not egoistically control the meat.
The single-butcherer archaeological pattern at 200,000 BP certainly seems to be consistent with this modern practice, and obviously the kind of LPA sharing system we have been talking about would not work efficiently if selfish alpha individuals remained as little restrained as they were in the epoch of Ancestral Pan, or as they may have been when earlier archaic humans went at carcasses so individualistically 400,000 years ago. All of this at least fits with the idea that a decisive system of political egalitarianism needed to be imposed if earlier humans were to regularly eat large-game meat with good nutritional efficiency, and—again—do so without undue conflict when lethal weapons were available to all.
Here, then, is a thesis that fits any of the above scenarios. Whenever it was that human groups became militant about their egalitarianism, logically it became highly adaptive for a band’s alpha types to very carefully hold their dominance tendencies in check—and I’ve suggested that this, along with similar effects on those prone to act as thieves or cheaters, could explain how humans acquired a conscience. We may assume that these selfish “deviants” were genetically variable in their capacity for self-control. We also may assume that when these would-be meat hogs began to be punished regularly and severely, for antisocially throwing their weight around, this would have brought on group conflict at much higher levels than are seen today when alpha suppression is quite well routinized in LPA bands. As a result, with groups basically winning out over individuals, strong social selection pressures would have been at work on the genotypes of those prone to lose.
Over time, the apelike, fear-based, ancestral version of personal self-control would have been augmented, as there appeared some kind of a protoconscience that no other animal was likely to evolve. That is my moral origins hypothesis. A question I shall not really attempt to answer is why bonobos and chimpanzees did not evolve in this same direction, given that they shared exactly the same major head starts. But the answer may lie largely in the fact that humans developed more complex social brains—or, possibly, that humans became dedicated large-game hunters.
Darwin believed all natural selection processes to be quite gradual and constant in doing their work, which was stimulated by gradual changes in the natural environment. However, a considered modern view is that sometimes such changes can be so radical, and sometimes so rapid, that what biologist Niles Eldredge called “punctuated equilibrium” takes place.69 This means that rates of genetic change may accelerate markedly owing to swift and major changes in the physical environment.
With respect to conscience evolution, there’s also a social environment to consider.70 If after hunting began alpha power was still substantial and punitive sanctioning had to become intensive, then just by itself punitive social selection could have provided a new kind of punctuation. I say this not only because intensification of capital punishment would have affected fitness so profoundly, but also because preference-based social selection would have been so well “focused” by human intentions. By this I mean that this selection force would have been subject to purposeful adjustments as everyday social problems were being coped with and crises resolved. In effect, the large brains of humans could have led to persistent patterns of ecologically oriented political problem solving,71 which over the long term could have had profound genetic consequences. In being heavily cultural, these problem-solving styles could have been adjusted quite quickly, as physical or social environments changed.
“Normal” natural selection processes require minimally about 1,000 generations (for humans, about 25,000 years would be the equivalent) to bring a new trait into existence. That’s what Edward O. Wilson told the world in 1978 when he wrote On Human Nature.72 Even if hunting large game was a relatively recent punctuation point, at which we may hypothesize that powerful social selection forces arose to purposefully favor individuals having superior self-control, there would have been plenty of time available for as profound a change as conscience origins to have taken place afterward, as humans were heading for cultural modernity. The time frame can be estimated rather precisely. Hunting became intensive a quarter of a million years ago, whereas cultural (and moral) modernity had arrived by 45,000 years ago or perhaps a bit earlier. Minimally, this would have allowed for 7–8,000 generations of gene selection to do their work in making us moral or in finishing that job, and with present knowledge I’m proposing that this was accomplished to a very significant degree by social selection, guided by highly consistent social preferences.
I must quickly say that with respect to our becoming altruistic, group selection, reciprocal altruism, and possibly all the other mechanisms discussed in Chapter 3 were likely to have been making contributions as well. But this is a question we will take up in Chapter 12.
What if definitive egalitarianism had fully arrived before large-game hunting phased in? Even though this would seem to be inconsistent with the mode of butchering that Stiner identified at 400,000 BP, with archaic Homo sapiens as the large-brained actors it is not difficult to imagine that egalitarianism might have arrived sometime between about 500,000 BP and 250,000 BP, while Homo erectus cannot be ruled out. However, whenever this did take place, we may assume that thieves, cheaters, and, especially, alphas were not going away quietly; that many were killed or otherwise disadvantaged along the way; and that the human capacity for self-control was advancing as a result of all of this drastic social selection. In fact, if we look at the not-infrequent social sanctioning of LPA foragers, with their rather frequent use of capital punishment, this process may still be in operation at the level of gene selection.
Why has social selection been given such priority here in comparison to the other models of selection I just mentioned? Let’s consider Darwinian sexual selection as one very fundamental type of social selection.73 Sexual selection operates strongly enough to support traits we must view as maladaptive and “exaggerated,” such as peacock tails. They can exist because evolved patterns of decisionmaking are channeling the selection process, giving it what might be called (at least metaphorically) a special “focus.” In fact, sexual selection is very well focused by innately guided female choice. Think about all of those peahens preferring the more vigorous and fit peacocks, the ones who advertise their genetic superiority with the more magnificent multispotted tails. Consider, as well, the wide variety of energetically costly and often quite “exaggerated” male courtship displays in other species, described so well by Darwin, that cater to female choice,74 and you’ll realize that a preference-based type of selection can have such strong effects that otherwise patently quite maladaptive traits can be selected in spite of their heavy costs in fitness. Indeed, these traits are being kept in place solely because they provide such huge compensatory reproductive benefits to the chosen males during mating season. In this light, in trying to assess the obvious power of preference-based sexual selection keyed to mating displays, British geneticist Ronald Fisher long ago referred to interactive, “runaway effects.”75
Punitive social selection is far from being identical. Common sense tells us right away, of course, that this can be a matter of being summarily executed—as opposed to receiving a satisfying sexual reward. Yet punishment, too, involves well-focused choices that also very directly affect reproductive success, for a dead would-be alpha male cannot breed. I hope that it will be possible some day to create mathematical models to take this special, group-actuated, punitive mode of selection into account more effectively. For now, however, I suggest that in helping a conscience to evolve, social selection could have acted quite strongly—strongly enough so it’s likely that our brains could easily have been redesigned to accommodate conscience functions over a period of 7–8,000 generations, and possibly much more.
Keep in mind that punitive social selection continues to this day, both among the world’s very few remaining viable foraging societies and in any other type of society that consistently punishes deviants who fail to control themselves. And keep in mind that among foragers there’s far more to such negative social selection than capital punishment. I’ve emphasized this very dramatic type of group punishment because of the heavy costs imposed, but prehistorically lesser social sanctions in all likelihood also had ample generations to work with, and even though their immediate effects surely were weaker, they probably would have been employed much more frequently. For instance, the long-term effects of being ostracized or totally shunned by the band can mount up, and even just having a shamefully poor moral reputation can adversely affect an evolutionary actor’s marital and other partnership prospects because of reputational liabilities.
Donald T. Campbell told us that when biological evolution takes place, the basic mechanisms involve what he called blind variation-and-selective-retention;76 he used all those hyphens to designate a single process that basically is devoid of purpose. This randomized process involves environmental pressures operating directly on the everyday phenotypes of variable individuals, with effects on gene pools and therefore on genotype. Here we’ve been concentrating on gang attacks and other group sanctions, and also as we’re about to see in more detail, reputational consequences that act as agencies of selection. These originate in social groups rather than in natural environments, so they merit some special interest.
It’s in this context that I’ve come up with a highly specific evolutionary hypothesis: The killing, wounding, social exclusion, and social avoidance of aggressive (or cunning) deviants who do not rein in their predatory tendencies could have influenced earlier human gene pools, affected them so profoundly that a uniquely human conscience was able to evolve.
This type of theory is not wholly novel, by any means. A small handful of other scholars have considered the possibility that punitive social selection can significantly affect gene pools, but they’ve done so in areas other than conscience. Not unsurprisingly, the original insight came from Darwin, even though the idea was not very well developed. Then forty years ago, in 1971, biologist Robert Trivers clearly identified as a selection force the “moralistic aggression” that hunter-gatherers are capable of.77 He suggested that when such aggression was turned against individuals who defaulted on reciprocating relationships, this would have reduced the frequencies of genes that made for cheating. I have included this basic idea in my model, even though the emphasis has been on bullies far more than on deceivers.
In the late 1970s biologist Richard D. Alexander also began to discuss social selection in humans—at least partly in terms of group punishment of cheating, as Trivers did, but mainly positively, in the context of mating choice, with worthier males being favored by females.78 Alexander’s student Mary Jane West-Eberhard went on to suggest that Darwinian sexual selection was just one type of social selection,79 and she exemplified other kinds of social selection using mainly insect examples. As a biologist she continues to work at the task of broadly defining social selection as a particular type of genetic selection that stems directly from the social situations or social preferences of individuals.
In 1987, in his important book The Biology of Moral Systems, Alexander elaborated his thoughts about how cooperative reciprocity in meat-sharing worked in hunter-gatherer bands and how the inherent altruistic traits might be selected. The main puzzle was the way hunter-gatherers shared meat without regard for who killed it, and the way their expectations were geared not to a “tit-for-tat” kind of payback, à la Trivers, but to what Alexander called a system of indirect reciprocity—an important concept that was introduced in Chapter 3. Briefly for now, this meant that others were being helped on the general assumption that “if I’m generous to someone today, someone will be generous to me in my time of need.”
Alexander was trying to define the altruism paradox strictly in terms of the practices of hunter-gatherers, and in this indirect reciprocity he saw a major puzzle. Obviously, in such a generalized system of giving and taking, the opportunistic free riders who took much more often than they gave would come out ahead in their personal fitness, while, conversely, the altruists who did more giving would come out with a deficit. This applied not only to the sharing of meat, but also to other beneficial behaviors, such as helping nonkin who become injured or ill or otherwise incapacitated.
Explaining how such systems could evolve involved two types of social selection. In viewing indirect reciprocity as a kind of insurance system for all band members,80 Alexander had this to say about the role of group punishment: “Obviously, various forms of punishment, including ostracism or social shunning, can . . . be applied to individuals repeatedly observed not to reciprocate adequately or follow whatever codes of conduct may exist.”81 Alexander went on to emphasize, even more, the importance of social status or “reputation” to reproductive success. Although his main emphasis was on good reputations and their importance to cooperation, at this stage of my own argument bad reputations—and their social and genetic consequences—are of special interest for understanding conscience origins. A substandard conscience can generate not only a substandard reputation, but active punishment as well.
Bad reputations are confirmed as community members gossip privately about the behavior of others. When groups of archaic hunters were coming down hard on their alphas, along with the thieves and cheaters in their midst, they very likely had the language skills to keep track of the deviants’ entire social histories, which meant they were able to make them pay not only for single transgressions but also for long-term patterns of malfeasance. Developing a superior conscience that could make similar cumulative calculations in adding up past social liabilities, and do so on an introspective basis that was private and accurate, helped the better equipped of these potential deviants to stay out of serious trouble. Thus, the genes involved in self-protective self-assessment and self-control could have been strongly supported by punitive social selection.
Genes for aggression would have been affected as well. In 1988, in analyzing capital punishment among nonliterate humans of various types, political anthropologist Keith Otterbein returned to Trivers’s original insight about moralistic aggression against cheaters to suggest that, over time, capital punishment could also have modified human gene pools to make our species less aggressive because the more aggressive types would have had their reproductive success curtailed.82 Since then, Richard Wrangham has discussed autodomestication in our species, partly in the context of group punishment’s having made our overall genetic nature less violently aggressive, and partly in the context of skeletal changes that go with the reduction of aggressive traits.83 Wrangham’s major interest in capital punishment as a social agency of gene selection parallels my own, and our views have been mutually reinforcing.
In 1999, in Hierarchy in the Forest, I considered the social selection effects of antihierarchical humans ganging up against their more forceful and willful superiors not only in this “curtailment of aggressivity” context, but also in a context that brought me to the present hypothesis about conscience evolution and moral origins. Here’s what I said, little imagining that I’d be writing a book on the subject: “With the reduced reproductive success of extreme upstart types, natural selection seems likely to have changed our political dispositions considerably. . . . This could have taken place through debilitation of aggressive responses, strengthening of inhibitory controls, or both.”84
It’s the second effect that we’re focusing on in this chapter, for strengthening of inhibitory self-control amounts to conscience evolution, and it describes a key aspect of moral origins. We may never be able to guess about what form a protoconscience took at the point when more efficient types of self-control were beginning to develop. However, I have at least suggested that the social scene in which this evolutionary development took place can be plausibly reconstructed on the basis of what we can suggest about Ancestral Pan’s behavior and what we know about today’s foragers and the problems they continue to face in keeping their social predators under control.
If we look back to Ancestral Pan, the only very likely type of decisive “social control” we’ve been able to reconstruct is rebellious coalitionary attacks that could have, on rather rare occasions, resulted in wounding, exile, or death. If we look to today’s foragers, it’s usually when the entire band’s social or economic welfare is threatened by an unrestrained deviant that moralistic social control by the entire band becomes decisive and coordinated, as well as severe and sometimes lethal. Today, this social selection continues to do two things as far as our gene pool is concerned. One is to reduce innate dispositions to bully or cheat. The other is to keep our conscience in place as a means of self-inhibiting antisocial deviance that can easily get us in trouble.
Later archaic humans with their assumed protoconsciences might strike us as nonmoral chimpanzees or bonobos strike us today. On the other hand, if we could observe them intensively, or subject them to experiments, we might sense that they had at least acquired some rudimentary feelings of “right and wrong” concerning the rules their groups subscribed to. We may never know. However, once earlier humans began to strongly internalize group values so that they were beginning to be guided by an internalized sense of right and wrong, I think we might perceive them as moral beings—particularly if we could listen to them talking about one another and if a judgmental tone of voice was used. And when they began to experience what we know as shame feelings and began to blush with shame, there would have been no question about their moral status.
Having a conscience is obviously of enormous importance to human social life, yet scientists seldom try to explain its origins. A sophisticated but limited theory is that of a pair of German psychologists named Eckart and Renate Voland,85 who make the interesting suggestion that a conscience evolved as a moralistic means for parents to get their innately self-interested children to pay back some of the investment made in parenting them. Obviously, this “parent-offspring conflict” thrust is far narrower than the social-selection-based hypothesis I’ve just proposed, which looks to how a conscience functions in human social life as a whole and how it might be “designed” to be adaptive. My hypothesis also is historical and considers our ecological past in connecting conscience evolution with changes in how humans exploited their natural environments. There are many other ahistorical approaches to explaining “moral origins” that likewise seem to stop short of seeing how moral behavior could fit into a more general evolutionary framework, and they will be considered in Chapter 12.
And then, of course, there are theology and myth. Here, some contradictions I sensed as a young boy going to Sunday school86 will briefly color the discussion. Both the Old Testament and the Koran portray an idyllic Middle Eastern Garden of Eden with abundant food and with no environmental dangers—aside from a manipulative serpent that comes and goes as it pleases and that, though certainly depicted as a most evil entity, may partly endear itself to some as a believer in free will and the quest for knowledge. Perhaps we should also add a vindictive Jehovah to this environmental dangers list, for it appears that this Supreme Being believed in entrapment. I say this because Adam and Eve could have looked forward to a potential eternity bathed in shameless innocence, with the race they’d founded living free of both social competition and moral compunctions—had Jehovah not set his trap. He baited it with attractively knowledgeable fruit, and human curiosity, urged on by a fearlessly free-lancing serpent, made Eve and Adam walk right in and put an end to what might have been (a somewhat boring) Paradise.
The scientific Garden of Eden that I discovered much later in life was quite different. It was anthropologically situated in the African Pleistocene, which provided some great opportunities in life but also some potentially very dangerous climatic instabilities, frequent hunger and hardships, real poisonous serpents, including hyperaggressive black mambas, and hungry big cats prowling around at night. But the writers of the Old Testament certainly got it right when they implicitly likened their original pair of humans to morally innocent animals, emphasizing that their fall led to moralistic worries about sexual modesty and many other things. The biblical story may be pure allegory, but it’s worth noting that the theme of human-animal differences, combined with moral origins, appears widely in the mythologies of nonliterate people. In such purely oral traditions, the question of how humans acquired a shameful sense of right and wrong is addressed so frequently that I would have to number the instances in the thousands, and these stories can be colorfully different—yet strikingly similar.
When I was a graduate student, I spent a summer conducting field investigations with a research team on the Navajo Reservation, and one of the things we investigated was Ichaa, or “Moth Sickness,” a type of mental illness that in Navajo belief befell young people who committed incest. There was a myth, relevant to the work I was doing, that I still remember very well. It was collected originally in the 1930s from a traditional Navajo by an anthropologically gifted Franciscan missionary named Father Berard Haile,87 and the informant had been raised by the hunting and gathering generation of Navajos who raided widely in the Southwest before their defeat and incarceration in the 1860s.
It seems that for Navajos the earlier forms of humanity were like insects, and therefore they were able to breed closely with one another in the absence of any incest rules. One of their clans even had an insect name—the Moth Clan—and very happily these earlier “humans” were able to marry within the family, where love is always the strongest. According to the Mothway myth, after actual humans arrived, they naïvely decided to abandon their custom of not allowing brothers and sisters to marry, planning instead to follow the example of their Moth Clan predecessors. These early people gathered at a high place on the top of a mesa and married all their children to each other, while others went down to the base of the cliff to prepare a huge bonfire around which all the happy brother-sister couples would dance the night away. But suddenly, like moths, the young people were inexorably attracted to the fire at the base of the cliff, and en masse they rushed over the edge, fell into the fire, and burned to death. The moral of the story: if you behave incestuously like a moth, you’re breaking a rule of nature and immanent punishment will follow. It was thus that the earlier Navajo people first met with crime and punishment.
The beauty of a fable, be it a Moslem or Judeo-Christian Garden of Eden story or the Navajos’ Mothway myth, lies in the storyteller’s using just a few poignant events to explain something as profound and complicated as human moral origins. The basis for believing these stories is “faith,” pure and simple. The beauty of a scientific story, such as the one I’m in the process of telling here, lies in the fact that the evidence is designed to be weighed and the theories are designed to be challenged and, where needed, modified. In making my case, I appeal not to faith but to anthropological data and insights, to the far-reaching logic of natural selection theory, to what we presently know about brain functions, to findings from primatology and archaeology, and to all the other modern knowledge we have at our disposal.
Broadly, a conscience provides us with a social mirror. By continually glancing at it, we can keep track of shameful pitfalls that threaten our reputational status or proudly and virtuously chart our personal progress as group members in good standing. But more than intellectual self-knowledge is at stake, for as a practical matter we’re continually trying to cope with our own powerful, well-evolved “appetites,” which so often are likely to land us in trouble with our groups. These run all the way from dominance tendencies to material greed and sexuality, and expressing them antisocially can create serious practical problems in everyday life.
Minimally, both the prefrontal cortex and the paralimbic system are involved in the emotional reactions88 that contribute to personal social strategizing and self-control. And when the effects of group punishment began to improve our capacities in these areas, it was individual differences in the relevant brain functions that punitive social selection was able to work on in terms of underlying genes. Of course, with this social type of selection, as with natural selection more generally, it was basically variation in the phenotype that selection processes acted upon directly.
Ultimately, the social preferences of groups were able to affect gene pools profoundly, and once we began to blush with shame, this surely meant that the evolution of conscientious self-control was well under way. The final result was a full-blown, sophisticated modern conscience, which helps us to make subtle decisions that involve balancing selfish interests in food, power, sex, or whatever against the need to maintain a decent personal moral reputation in society and to feel socially valuable as a person. The cognitive beauty of having such a conscience is that it directly facilitates making useful social decisions and avoiding negative social consequences. Its emotional beauty comes from the fact that we in effect bond with the values and rules of our groups, which means we can internalize our group’s mores, judge ourselves as well as others, and, hopefully, end up with self-respect.
In the 1800s, Darwin knew in general that moral capacities were the product of our brains, but today we’re beginning to put some of the specific pieces together. Psychologist Jonathan Haidt has demonstrated that our initial moralistic reactions can be based heavily on emotions, perhaps even more so than upon intellectual understandings.89 As I’ve defined the matter, our consciences afford us the capacity to look back into the social past or forward into the social future, weigh the consequences of our actions with feeling, and adjust our behavior accordingly.
This same modern conscience goes beyond automatic self-inhibition and social strategizing, for some of us use language to literally talk to ourselves as we try to define, and if we can to resolve, the thorny moral dilemmas we sometimes face. In a sense our inner life is oriented to choosing lessers of two evils, and this capacity has been tested academically using MRI scanning at the level of the hypotheticals mentioned earlier. Some rather nasty favorites of philosophers include a burning house from which you (an adult subject) may rescue, say, either your mother or your sister but not both, or a situation in which you can stop a runaway trolley car and save five lives but only if you push the fat guy off the bridge and arrest the trolley’s progress by deliberately making him die.90 As we’ll see, Inuit-speakers in the Arctic do something quite similar with their children in real, everyday life.
Much more likely moral dilemmas, which many Americans actually face as children or as young adults, include whether to engage in the underaged or otherwise illegal use of a “substance,” whether to shoplift, or when driving whether to “stretch” a red light when doing so will “safely” save some precious time. Later in life, with half of our marriages experiencing adultery, the moral dilemma can be whether to stray and hurt the one we love. And then there’s the matter of fudging an income tax return, which for many isn’t much of a dilemma at all, morally speaking, because “the government” is conveniently defined as an alien predator. Such dilemmas abound all around us, and it’s our consciences that guide us in resolving them. But even if we do manage to resist a particular temptation, the dilemma may still be there in the form of a strong psychological ambivalence that is not fully resolved.
It’s through the conscience that such dilemmas are identified as problematic, and it’s the conscience that mediates such ambivalences. Individuals can be highly variable in how they cope with these and other, more serious moral dilemmas, for some of us tend to be impulsive initially, with our consciences becoming active afterward in a damage-control mode, whereas others remain perpetually tempted but holding back. And then at the extremes are those who have internalized their group’s cultural prohibitions so well that they are barely tempted, and of course they contrast sharply with the unrestrained psychopaths at the other end of the spectrum, the weakly conscienced people who were discussed in Chapter 2.
There also are “immoralists” who seem to take delight in breaking rules just to be breaking them, and in some modern nations this last reaction seems to be incorporated into youth cultures. We also have full-blown, rule-based alternative criminal cultures, with gangs (and, unfortunately, prisons) as their special breeding grounds. On the other hand, we also have monastic cultures in which individuals take oaths to live in a morally superior way and perhaps, like Thomas Aquinas, find their consciences being overworked because their naturally based ambivalences are so strong and their moral standards are so high.
I shall not try to suggest how all of these complex reactions evolved, but it’s apparent that we’ve moved well beyond the rather straightforward, mainly fear-based modes of self-restraint found in the African great apes, including even apes raised by highly moralistic humans. Morality involves this special kind of self-consciousness we call a conscience, which enables us to think about several important things at the same time. One is the rules we’ve internalized, and another is our immediate desires. And then there are our larger social objectives in life, such as gaining a good moral reputation and avoiding a bad one. A conscience is the mediator of all this, and it’s well evolved to do so.
We may tend to think of our consciences mainly as psychological agencies of moralistic self-control, as Darwin did, but I’ve suggested that we may define the evolutionary conscience as having functions that are much broader. An opportunistic, “Alexandrian” conscience enables us to predict the social reactions of our peers and to calculate what we can get away with socially and still keep up a decent moral reputation.91 It also allows us to decide that a particular transgression is just plain worth it—even assuming that public discovery is likely. And it lets saintly types like the Mother Teresas of this world strategize their behavior so as to maximize their reputations and perhaps gain thereby, even though often enough their main motives may be altruistic.
The optimal evolutionary conscience, then, is not a perfect and complete instrument of rule internalization that makes self-inhibition automatic and might work very nicely in an anthill. Among humans things are quite different because individuals who take society’s rules too literally, and therefore are too inhibited to behave with some moral flexibility, will usually find themselves at a competitive disadvantage with respect to relative fitness. Rather, a fitness-optimizing conscience is one that permits some bending of lesser rules for personal advantage, even as it recognizes which rules should never be bent because doing so will bring dire personal results. This is an argument from adaptive design. But it also fits quite nicely with what can be learned ethnographically about LPA hunter-gatherers and with what we can learn in a Cartesian manner by peering into our own evolved psyches.
We now have a hypothesis about how moral origins began, for in all probability gaining a self-regulating conscience was the first milepost in human moral evolution. Basically, we’ve moved from a wolflike or apelike “might is right,” fear-based social order to one also based on internalizing rules and worrying about personal reputations. This was enough to make us unique in the animal kingdom, but the real clincher was blushing with shame—a mystery of natural selection that no scholar has begun to explain to date. In terms of evolutionary priority, it seems to me that the internalization of rules and values probably came first, as one basic function of the evolutionary conscience, and that blushing somehow became associated with these self-control functions afterward. But this is sheer speculation. If someday the genes involved with socially triggered facial flushing and other moral reactions can be identified, a more specific theory might be offered and a chronological hypothesis might even be possible.
Becoming moral did not mean that our typical temptations were about to go away as facts of human life. Rather, they became entwined with feelings of anticipatory shame that had the effect of automatically inhibiting antisocial behavior from the inside. Nor did becoming moral mean that ancestral-type fear motivations were going away. We still behave ourselves in part because we dread the moral outrage of our peers—or, today, police intervention as well.
What happened was that the nature of self-control was transformed in ways that no scientist could have predicted—even though in hindsight some useful preadaptations are fairly obvious. And once people were becoming moral, their consciences did more than guide and inhibit them. We moved from being a “dominance-obsessed” species that paid a lot of attention to the power of high-ranking others, to one that talked incessantly about the moral reputations of other group members, began to consciously define its more obvious social problems in terms of right and wrong, and as a routine matter began to deal collectively with the deviants in its bands. In important ways the dominance of the group was superseding the dominance of individuals; indeed, the well-known social tyranny of small groups has been well appreciated (and resented) by potential or actual deviants for at least tens of thousands of years.
As we began to create the kind of gossipy, socially conformist moral communities that Durkheim described so well, the sense of right and wrong afforded by a conscience was able to transform group social control. It was by achieving a moral consensus that people who were threatened by serious social predation could connect with others, and do this so strongly that they could reach a point of shared moral outrage that simply by its threat could deter many a potential deviant. In their actual expression, the resultant punitive actions led to effective and usually safe elimination of those whose conduct seriously threatened or injured the common good.
As our gene pools changed as a result, an increasingly moral social life offered new evolutionary possibilities, which have been experienced by no other species. And one of these possibilities was the rise of altruistic tendencies as hunter-gatherers began to deliberately harness the good they saw in human nature. The result was social selection of a very different type, that contributed significantly to our becoming a species noted for its altruism.