While reading an article on Inuit shamanism yesterday, this passage offered confirmation:

Shamanic traditions were embedded in a wider cosmological framework that still operates. This cosmological framework concerns a wide range of features such as respect for animals, the beliefs in tarniit (shades, souls), tuurngait, nonhuman beings (such as ijirait [caribou-people] and tuniit [people who inhabited the land before the Inuit]), the Inuit naming system, the sharing of country food, the need to communicate or confess transgressions or exceptional experiences, tirigusuusiit (the following of old rules and taboos), ritual injunctions, and many other features, all of which play a part in modern Inuit society. Thus the notion that animals will only offer themselves to human beings if they are treated with respect and not abused is recurrent in Inuit discourse.

As is evident, foraging and social knowledge is inextricably linked to Inuit oral traditions.

While this makes for a plausible story, there are a number of problems. The first is that we have little archaeological evidence of ritual behaviors, especially those that would have been group oriented. While some have argued that evidence of symbolic thinking – in the form of decoration-adornment and markings on material objects – indicates ritual behavior, this linkage is attenuated at best and imaginary at worst. While wearing perforated shell or decorating material objects is suggestive, such displays neither entail nor require ritual-religious behavior.

A simpler explanation is that people were using such items as social markers, to individuate themselves and perhaps signal to others identity or status. There remains a large gap between these artifacts and the kinds of group ritual activities, such as singing and dancing, that some have imagined. While such data do not rule out ritual or proto-religious behaviors, they constitute sparse evidence for ruling them in.

Bigger Groups Win

The second major problem – the one I wish to focus on here, concerns competition between groups. What makes one group more successful than another?  In nearly all cases involving competing groups of social mammals, larger groups out-compete smaller ones.  The reasons are fairly obvious and supported by the evidence: larger groups have lower predation risk and have greater success in agonistic encounters between groups. They have larger ranges or territories, and when resources are depleted or disappear, migration – usually a hazardous undertaking, is more feasible. When a larger group of social mammals encounters a smaller one, the larger nearly always prevails. Larger groups also have a greater store of collective knowledge with respect to nearly everything that matters – water, food, shelter, and predators.

While there are several factors that impact group size, ecological ones being foremost, it is safe to say that ritualistic or proto-religious behaviors are not among them.  Highly social mammals are for the most part bound together by that most powerful of evolutionary bonds: genetic kinship.  Extraneous factors need not be invoked to explain cooperative or even altruistic behavior.  Inclusive fitness is sufficient.

Talking about Tools

Focusing specifically on hominins, there are two factors that would have decisively impacted the size and ultimate success of Paleolithic groups: language and technology. One need not accept the “social grooming” hypothesis to realize that language (or advanced forms of proto-language) is a game changer when it comes to cooperation and cohesion.  In addition to the planning and coordination it would have enabled, language at some point made possible notions of extended and fictive kinship, further strengthening this most powerful form of social glue.

For at least 2.5 million years and probably longer, technology has been a defining characteristic of hominins. Although there are broad progressive technological trends in the lithic record, it is also clear there were long periods of stasis and even reversion. Few things would have had a greater impact on any given group’s odds of success than its technologies. Although apparently slight advances (such as material choice and flaking methods) were undoubtedly advantageous, other technologies were – like language – game changers. The control of fire is obviously one of these. The first groups to develop composite weapons, spear throwers, and bows-arrows would have had immense advantages over other groups, not only in hunting but also in warfare. For groups radiating toward northern latitudes, clothing would have provided similar benefits.

In sum and in rough order of importance to the success of any given hominin group, the factors that would have had the greatest impact intergroup competition are: (1) group size; (2) proto-language or language; and (3) technology. Any group having advantages in one or more of these areas would have been better able to compete against groups deficient in them, but which might have had the kind proto-religion or ritual that enhances group solidarity and commitment.  Such solidarity and commitment is, of course, determined in the first instance by kinship, which is not dependent on proto-religion or ritual for its efficacy.

It seems unlikely that proto-religion or ritual provided any groups with advantages with respect to language or technology. No one has ever suggested that language evolved or technology progressed because either was linked to the supernatural. Given this fact, and the paramount importance of group size to group success in ancestral environments, the critical question facing advocates of group level selection as the functional impetus for the evolution of religion is: Did proto-religion enable Paleolithic hominins to form larger groups? If group ritual oriented around supernatural beliefs somehow resulted in larger groups, then the “religion evolved as a group level adaptation” story may have legs.

Paleolithic Group Size – No Religion Necessary

Let us assume, for the sake of argument, that at some point during the middle or upper Paleolithic, certain groups developed proto-religious ideas that promoted ritual activities and resulted in increased cooperation or cohesion. Do we have any reason to think that such ideas or activities also resulted in larger groups, which the single best predictor of success when it comes to group competition? While we can speculate on the ways in which proto-religion might have affected group size, a better method is to look for evidence that hominin group sizes increased during the Paleolithic. If we can identify increases in group size among Paleolithic hunter-gatherers, we can then ask whether the larger groups were enabled or caused by proto-religion.

Because we do not have direct evidence of Paleolithic group size, we have to rely on proxies and analogies, however imperfect. As a proxy, we can examine primate group size. For an analogy, we can examine known hunter-gatherer groups. Although primates obviously do not have anything like proto-religion, it is reasonably safe to assume that the factors affecting primate group size are similar to those that would have affected hominin group size. As for known hunter-gatherers, they do have something akin to “religion,” although their loosely organized, non-systematic, and individualized shamanic practices bear few resemblances to the kinds of religions that humans systematically developed in conjunction with agriculture. If we can identify groups that grew over time or were larger than others, we can ask whether the observed size increase was connected to supernatural-religious beliefs, or whether other factors better explain the larger groups.

Because there are over 300 species of extant primates, it should come as no surprise that group size (and composition) varies considerably; the range is from a few family members to a few hundred. While several variables affect group size, the most important are predation risk, resource density, and neocortex size. The latter speaks to the tremendous load that intense sociality places on cognition and memory.

Chimpanzees and baboons are perhaps the most relevant models; the former because they are the most closely related to hominins and the latter because they are largely terrestrial and live in relatively stable multi-male and multi-female groups. Many researchers are of the opinion that this mode and composition most closely resembles the ancestral hominin condition. Chimp group size varies from 15 to 65 and the mean, other factors being equal, is approximately 30. Baboon group size varies from 25 to 250, with a mean near 100.

Remarkably, these numbers are quite similar to those of known hunter-gatherers. The basic foraging unit – which usually includes a few related families – consistently clusters around 30 people. This group typically maintains close ties to neighboring groups that are similarly sized and genetically related. The units occasionally aggregate into a group that averages 150 members, most of whom are related. This fairly tight knit group is primary, and is the one that can be counted immediately counted on in times of need. In most cases, these primary groups of 150 maintain kinship ties with surrounding groups of similar size, with the result being that a kinship group of approximately 500 constitutes the larger regional network that may come together only infrequently. This secondary group is typically the largest and hunter-gatherer groups rarely exceed this number. Beyond the regional network group of 500, relations are attenuated and conflict more likely. This pattern (basic = 30, primary = 150, secondary = 500) is fairly consistent across time and space.

This consistency in forager group size, when coupled with similar group sizes for chimps and baboons, leads to the conclusion that the upper limits of hominin group size remained relatively stable for much of human evolution. These limits and groupings were, of course, substantially altered by the dynamics of domestication; with agriculture and sedentism, human group size increased substantially. It is at this time, when groups become larger than 30-150-500, that kinship glue is no longer able to hold people together, and collective abstractions – such as polity or religion – are required to maintain larger groups. For most humans in the world, this fundamental transition (from foraging to agriculture) occurred no more than 7,500 years ago.

No Group Evolution of “Religion”

Where does this leave us? It means there is no need to invoke religion or ritual to explain group level success. Given the limited group sizes we are talking about for most of human evolution, other factors – such as language and technology – would have had far more profound effects on the success of one group versus another. Kinship, both real and fictive, is more than sufficient to bind such limited-size groups together and make them cohesive, cooperative, and altruistic. This is not to say that proto-religion and ritual would not have had an impact, but it is difficult to imagine the circumstances under which a “religious” 30 member group would prevail over a “non-religious” 150 member group. If group sizes were equal, and one group was proto-religious but the other was not, other factors would have been more decisive in determining the outcome of any conflict between them.

It is only when all primary variables are equal – group size, linguistic ability, and technological prowess – that a proto-religious group may have had some kind of advantage due to increased cohesion or cooperation. This places religion far down on the list of factors that explain group success during the Paleolithic. It also means that “religion” did not evolve because it made some groups more competitive than others.

Sources:

Aiello, Leslie and Dunbar, Robin. 1993. “Neocortex Size, Group Size, and the Evolution of Language.” Current Anthropology, 34(2):184-193.

Baer, Darius and McEachron, Donald. 1982. “A Review of Selected Sociobiological Principles: Application to Hominid Evolution — The Development of Group Social Structure.” J. Social Bio. Struct., 5:69-90.

Isbell, Lynne and Young, Truman. 1996. “The evolution of bipedalism in hominids and reduced group size in chimpanzees: alternative responses to decreasing resource availability.” Journal of Human Evolution, 30:389–397

Janson, Charles and Goldsmith, Michele. 1995. “Predicting Group Size in Primates: Foraging Costs and Predation Risks.” Behavioral Ecology, 6(3):: 326-336.

Kosse, Kristinza. 1989. “Group Size and Societal Complexity: Thresholds in Long Term Memory.” J. Anth. Arch., 9:275-303.

Marlowe, Frank. 2005. “Hunter Gatherers and Human Evolution.” Evolutionary Anthropology, 14:54 –67.

Wrangham, Richard, et al. 1993. “Constraints on Group Size in Primates and Carnivores: Population Density and Day-Range as Assays of Exploitation Competition.” Behavioral Ecology and Sociobiology, 32(3)199-209.

There’s been a minor explosion of punditry about the evolution of religion, some of it naive and some of it making my blood boil. It seems that it was Jesse Bering who kicked it off. Before Christmas, he wrote up Michael Blume’s research into religion and fertility. Then in the New Year, Jonathan Leake picked up the story in the Sunday Times. Most recently, Nick Spencer took up the cudgels in the Guardian.

Each of them made me more exasperated than the last! And what is it that’s got them so excited? Well, it’s the idea that the relatively higher fertility rate of the religious in the modern world means that religion is somehow at the apex at the tree of life.

In the remainder of his post, Tom explains in three steps why religion did not evolve as a fertility adaptation. It’s a good start, to which I will add three additional reasons:

1. “Religion” is a modern construct — this social/cultural package did not evolve at some point during the Paleolithic. There was nothing like “modern religion” during the Paleolithic.

2. We cannot study modern religions — which are fundamentally and profoundly different from the supernatural beliefs/practices of Paleolithic humans — and say that because modern religions promote fertility, Paleolithic supernaturalism did the same.

3. The relevant study group for the “evolution of religion” (a terribly misleading phrase for the reason stated in point one) would be Paleolithic hunter-gatherers, not any religious group that has existed since the advent of agriculture.

It should go without saying that studying modern religious groups and projecting them back in time tens of thousands of years — to some imaginary origin point for “religion” — is an invalid method, both logically and historically.  But it apparently needs to be said.

The fallacy of this approach is basic and can be highlighted in many ways. I will provide but one example.

It is a proven demographic fact that around the world, people of low socioeconomic status have much higher fertility rates than people of high socioeconomic status. Does this mean that poverty is an adaptation? Obviously not. Neither is “religion.”

Underlying most of this talk is an implicit assumption: that a lack of religious knowledge is a bad thing. While I do not want to argue the point here, I think this assumption is well supported on several levels, the most important being a simultaneously conservative and Nietzschean concern for truth.

If truth about the beliefs which we characterize as supernatural and religious is a goal, an obvious question arises: What do we need to learn?  This is the question Diane Winston recently asked without providing much of an answer, other than “Knowing a bit of theology and religious history is good a first step.”  I would reverse that order and suggest the teaching religious history is essential — theology detached from the historical contexts in which it was created not only is bland; it is also misleading.

For quite some time, Daniel Dennett has been arguing (see this TED talk where he dismantles Rick Warren’s purpose pabulum) for a broadly enhanced religion curriculum that, in the end, would enable young people to choose a faith — or decline it altogether — because of truth correspondence.  This correspondence, however, goes far beyond apprehending which theology seems most agreeable or sensible; it includes evolutionary approaches to metaphysics.  As Dennett contends in Breaking the Spell, supernatural beliefs can be understood and are explicable as something entirely natural, but what we today call “religions” are produced by humans.

Achieving this understanding requires more than a “bit” of teaching about religious history.  It requires a curriculum (or course) organized along these broad lines:

1.  Deep History: the evolution of a brain-mind that generates supernatural concepts and beliefs;

2.  Paleolithic History: the manifestation of supernatural thinking as shamanisms; and

3.  Neolithic History: the transformation of shamanisms into more organized and systematic forms of belief that we call “religions.”

The philosopher and historian of science Michael Ruse has a nice piece titled “Darwinism and the Moral Argument for God,” in which he discusses the religion deflating research demonstrating that morality has no necessary linkage to God or religion.  This is of course true, as I explained in Religion Functions to Sustain the Moral Order — Starkly Wrong.  Aside from the considerable body of research showing that primates possess proto-morality (see Frans de Waal’s work) and that humans have evolved moral sensibilities (see Marc Hauser’s work), one should also consider that most or all hunting and gathering groups had distinct moral codes that were unwritten and unattached to notions of deity.  These codes became considerably more complex after the Neolithic Revolution, when writing first appeared and organized-systematic religions were formed. You can, in other words, have morals without religion.

Dzogchen Ponlop Rinpoche has posted an article asking: “Is Buddhism a Religion?”  Although Rinpoche’s version of Buddhism is non-religious, the fact remains that many practicing Buddhists around the world believe in a kind of Buddhism and engage in various Buddhist practices that are distinctly “religious.”  Rinpoche’s version of Buddhism is a recent incarnation that is highly westernized:

If you are interested in “meeting the Buddha” and following his example, then you should realize that the path the Buddha taught is primarily a study of your own mind and a system for training your mind. This path is spiritual, not religious. Its goal is self-knowledge, not salvation; freedom, not heaven. And it is deeply personal. Without your curiosity and questions and your open mind, there is no spiritual path, no journey to be taken, even if you adopt all the forms of the tradition.

This version of Buddhism is also tightly linked to the concept of the secular (see Talal Asad’s work) and concomitant privatization of belief.

Finally, Paul Wagler has posted on the early history of Christianity — “Ancient Empires: Reflections on the Spiritual Conquerers of the First Century.”  This story is interesting insofar as it goes, but a more complete history of Christianity and empire would discuss the marriage of Christianity to power that came with the Roman Emperor Constantine’s (272-337 CE) conversion and the subsequent adoption of Christianity as the official state religion.  This was perhaps the most fortuitous of all events in Christian history, and it resulted in Christianity becoming a “world religion.”  Without Constantine’s conversion, Christianity may have remained an esoteric Mediterranean religious sect.

“There is a fundamental difference between religion, which is based on authority, [and] science, which is based on observation and reason. Science will win because it works.”

Science and religion — neither of which exist as entities that have agency (i.e., they are abstract concepts) — are not in a contest.  Therefore, neither science nor religion can “win” anything.

What Sawyer should have asked was whether positivist inquiry can explain or account for religion.  What Hawking should have said is: “Yes.  We are already able to explain the brain-mind functions that result in supernatural thinking.  Humans have created bodies of belief and practice — which today we call religion — that depend on these brain-mind functions.”  Neither Sawyer nor Hawking seems to understand that science and history, working together, are largely capable of explaining religion.

With this in mind, let us look at this excerpt from Heussner’s report:

“What could define God [is thinking of God] as the embodiment of the laws of nature. However, this is not what most people would think of that God,” Hawking told Sawyer. “They made a human-like being with whom one can have a personal relationship. When you look at the vast size of the universe and how insignificant an accidental human life is in it, that seems most impossible.”

Here is where Hawking’s ignorance of religious history comes into play.  Not all peoples at all times have conceived of a singular God who is human-like.  In fact, we can trace the genealogy of this idea or particular concept of God.

Few if any hunter-gatherers or foragers believe in anthropomorphic or human-like gods and spirits.  Instead, they tend to perceive the entire world and everything in it as being animated by spirit or spirits.  Because all humans were hunter-gatherers until approximately 10,000 years ago, it is fairly safe to assume that anthropomorphic gods-spirits are a more recent development.  And indeed, we find this to be the case.

The idea of anthropomorphic or human-like gods originates in the earliest city-states located in Mesopotamia and the Levant.  This was no accident.  The elites and rulers of those city-states found it useful to conceive of gods in human terms — the earliest theologians (who always served earthly kings and rulers) reasoned that the earthly order was a reflection of the spiritual order.  Because there were kings and rulers on earth, there must be kings and rulers in the spirit realm.  And because kings and rulers on earth were humans, they thought that the kings and rulers of the spirit world must be like humans.

It was in this milieu that some groups, the Hebrews in particular, began to conceive of a high god who ruled over other gods.  The Babylonians had a similar idea about the supremacy of their high god.  Over time, the Hebrews extended this idea and began to claim that there was only one God whose name was Yahweh.  For those interested in this history and progression, I recommend Roy Rosenberg’s superb article, “Yahweh Becomes King.”

In the meantime, it would be helpful if physicists kept their mystical and religious ideas to themselves.  They always seem to be commenting on things that have nothing to do with space, time, and the cosmos.

When I lecture or write on this critical — albeit little known — topic, I like to use a string of “s” words to describe the consequences of domestication:

• Sedentism
• Surplus
• Specialization
• Stratification
• Sickness

These seemingly innocuous words are but basic descriptions for much larger changes in population, politics, warfare, economy, and religion.  The default assumption for most people seems to be that these changes were an unmitigated improvement and herald the dawn of “civilization.”

I have never been convinced that these effects were for the better; in that sense, I am a proud member of the “Paleoterrific” crowd.  This first dawned on me after reading Marshall Sahlins’ classic article, “The Original Affluent Society” and his book on paleolithic lifeways, Stone Age Economics.  Both should be required reading for those who believe that post-Neolithic civilization has been good either for humanity or earth.  Since first reading Sahlins’ article and book, I have read hundreds of ethnohistories and ethnographies on hunter-gatherers, including archaeological assessments of foraging, and nothing has changed my mind.

Although these issues do not receive much attention in the popular press, the BBC’s science reporter Paul Rincon recently interviewed Dr. Spencer Wells, who is the geneticist, anthropologist, and explorer in residence at the National Geographic Society (sounds like a very nice job).  During the interview, “Sting in the Tail of the Farming Revolution,” Wells expounded on the problems resulting from intensive agriculture, which makes everything else about “civilization” possible:

In [my new book Pandora's Seed], I talk about global warming and overpopulation. I trace a lot of these issues back in time to the dawn of the Neolithic. This was a period when humanity made a sea change in its culture. We settled down and started growing our own food.

Given that it has been so successful – 99.99% of the people in the world today are agriculturalists, and hunter-gatherers are a tiny minority – you would guess that it is successful for a reason. That it is a wonderful way of life, improved our health and so on.

It turns out, that’s not actually the case. Even if you look at very early communities, as they made the transition from a hunting and gathering lifestyle to farming in the same region, they became less healthy. They ended up shorter, they tended to die younger, the skeletal structure changed in a way that’s consistent with a decreased level of nutrition. So the question is why did (farming) win out?

Wells provides a climatological explanation, which may be partially correct and even necessary, but it is not sufficient.  Any explanation that fails to include the inexorable and uncontrollable drive to have sex and reproduce cannot be complete.  Regardless, Wells ascertains that farming has led to many unexpected and unpleasant consequences from which there may be no turning back:

Wells: But unfortunately, [the agricultural revolution] had lots of ancillary baggage. And the book is really about tracing that ancillary baggage. Diabetes, obesity, mental illness, climate change.

Rincon: How would people in western societies fare now if we had to be more like hunter-gatherers again?

Wells: I think we’d be in trouble (laughs). I think I’m probably romanticising hunter-gatherers somewhat in the book. But I have spent time with these groups and there is this remarkable sense of calm and almost coming home after a few days.

And it’s because they utilise so much of what it is to be human. So many different parts of the brain – their natural history knowledge is extraordinary.

Then there are the tracking skills, the hunting skills, the gathering skills, knowing where to find things at particular times of year. Even though it looks like a desert, you know where to dig down and find a tuber that’s going to keep you alive for a few more days.

We’ve lost all of that, and I think we’ve lost a lot in the process. We live in a very technological world, where everything’s available to us on Google. But if we lost that ability to Google things and we had to go out and subsist for ourselves in a marginal environment, I don’t know that we’d be able to do it. Once you lose it, it’s very difficult to get it back.

Wells’ ancillary baggage list is actually pretty tame; the slaughterbench of post-Neolithic history is perverse and the destruction of the earth’s plants, animals, and environment proceeds without pause.  The disaster in the Gulf is but the latest example, and is symptomatic of post-Neolithic societies. To this dismal list, I would add the all-important breakup of extended kinship groups, communal sharing of resources, and egalitarian ways of hunter-gatherers.

The Lakota and other Native Americans had good reason for resisting the advance of European civilization and detesting nearly everything about it, beginning with its intense focus on individualism, acquisition, consumption, and materialism.  Most of them thought the same of its pessimistic, prescriptive, doctrinal, and intolerant religious practices.

Michael:  I appreciate your discussions of evolutionary hypotheses of religion very much! But I wonder why I couldn’t find anything about the (on average) higher numbers of children by religionists, even if controlled for education, income and other factors. Religious tend to be fruitfull and multiply throughout the generations – which is a direct fitness advantage.

Cris:  My short answer is this: I am generally hesitant to look at modern religions — their forms, beliefs, practices (and fertility rates), and then project those back into evolutionary time. Doing so poses serious methodological problems. Indeed, it is my contention that there was no such thing as “religion,” in any organized or systematic sense, until well after the Neolithic Revolution approximately 12,000 years ago.

The first evidence of organized and systematic religion, in the modern sense, comes from Mesopotamia and Egypt, and thus dates to approximately 5,000 years ago. By this time, the forces of culture appear to have been far more important to humanity than the forces of selection. Thus, while organized religions may have increased fertility rates over the last 5,000 years, I am not certain it had anything to do with fertility rates during the preceding 150,000 years, which is when Homo sapiens first appears in the archaeological record.

Although I dislike the term “cultural evolution” (because I think the concept of “evolution” should be restricted to biology), it seems to me that most analyses of post-Neolithic, historically known, or modern religions are looking at “cultural evolution” rather than biological evolution. Cultural factors such as religion, in other words, were driving fertility rates but not doing much to shape the genomes or phenotypes of humans over the last 5,000 years.

Before there were any modern religions (i.e., before 5,000 years ago), there were shamanisms (the spiritual traditions which everywhere preceded the rise of organized religions). Thus, if I wanted to test the hypothesis that spiritualism in the form of shamanisms affected fertility rates, I would be looking at the reproductive fitness of shamanistic groups.

Because nearly all shamanistic groups over the past 100,000 years were hunter-gatherers, I think you will find that they deliberately depressed fertility rates through various methods, including extended lactation, abortion, and infanticide. All hominids and humans hunted and gathered for nearly 99% of their existence on earth, and whatever their spiritual/religious practices were, one thing is certain: they could not afford many offspring and took great care to limit group size.

This would seem to argue against religion playing much of a role in reproductive fitness, at least until quite recently in human history.

Michael:  That’s an interesting perspective! Nevertheless, I would like to point out three main arguments against this sidestep:

1.  If an evolutionary function is observable among contemporary humans, one would have to explain why it shouldn’t have been in older times. In fact, Sarah Hrdy emphasized the role of cooperative breeding (related to mythologies and religious “as-if kin”) especially (!) among the cultures of hunters and gatherers! I discussed her convincing stand here.

2.  Among contemporary, egalitarian hunters and gatherers without religious institutions etc. as e.g. the !Kung San, the Hadza etc., religious mythologies and commandments “are” emphasizing pro-family values, children etc., as well.

3.  A great deal of the available symbols and statues of pre-historic times is dealing with topics of sexuality and especially fertility, e.g. female figurines giving birth. This would hardly have been the case if reproduction had been a no-topic or even a negative one in our ancestor’s mythologies.

Cris:  Your points are well taken and I do not want to sidestep them.  What I want to do is adhere to chronology and be parsimonious with data.  I am on guard, in other words, against drawing unwarranted inferences.  Such inferences often arise when we assume that the way something functions today functioned the same way in the past.  More fundamentally, the problem is assuming that something as complex as “religion” even existed in the past.  The final problem arises from the assumption — pervasive in evolutionary biology and psychology — that the current function of a physical feature or behavioral trait indicates that it was targeted by selection and therefore is adaptive.

In their classic article, “The Spandrels of San Marcos and the Panglossian Paradigm: A Critique of the Adaptationist Programme,” Stephen Jay Gould and Richard Lewontin examined these assumptions and made a compelling case for caution.  We should not, in other words, be telling “just so” stories based on current functions that appear to be adaptive in modern settings.  From this perspective, religion is what Gould and Lewontin would call a “spandrel.”  I would also call religion a spandrel (or byproduct of other neural functions), in part for reasons I discussed in Religion as Evolved Adaptation: The Fallacy of Backwards Projection.

I am familiar with Sarah Hrdy’s work and admire it greatly.  On reading your post about her excellent book, Mothers and Others: The Evolutionary Origins of Mutual Understanding, one of the first things I noticed was that you discuss it primarily in the context of modern forms of religion — none of which (except shamanisms) were present in our evolutionary past (i.e., before 5,000 years ago):

Hrdy rightfully observes that religious mythologies is legitimizing distinct family models and organizing cooperative childcare. Not only Mother Church (!) provided assistance and later education to families and children (including the often-quoted “widows and orphans”), as did the Muslim Umma (from arab. umm = mother). Religious personnel is frequently called in the terms of as-if kin, e.g. as Father (Pater), Mother, Brother, Sister, the “Nun” etymological closely related to the “Nanny”. Shamans are communicating with the ancestors, emphasizing familial as well as mythological relationships.

If you look at Europe and beyond, religious communities today are increasingly focussing on their central competences – successful religions bestowing massive reproductive advantages upon their adherents in contrast to the less-reproducing seculars. We don’t have to speculate about the evolutionary mechanism: We are able to observe it, today and worldwide.

I do not deny that historically and ethnographically known shamanisms at times concerned themselves with fertility and reproduction.  My reading of the shamanistic record, however, does not indicate that increased fertility and child rearing was a primary preoccupation of shamans and their clients.  Although I have read most of the literature on shamanisms, I have yet to encounter a shamanistic practice or tradition that is linked to alloparenting, which is what Sarah Hrdy is discussing.

One last point regarding historical demographics, which admittedly are a bit speculative but are supported by genomic studies.  Most historical demographers estimate the world population — just before the Neolithic Revolution and domestication of plants-animals — to be in the range of 3-5  million people (though I have seen even lower estimates, around 1.5 million people worldwide).  All these people were hunter-gatherers and for a world-wide population count, these numbers are astonishingly low.

I think it no accident that the first organized and systematic religions appear in conjunction with the Neolithic Revolution and subsequent population explosion.  Evolution, however, involves more than just fertility rates or reproductive fitness.  Let’s take Judaism as a simple example of a religion that resulted in increased fertility rates.  How did this increased fertility affect genomes or phenotypes?  Which traits were under selection within Judaic groups?  Is there any evidence of a selective sweep — or allele fixation — within Judaic groups?

Michael:  Well, if I may condense your answer, it sounds like: I am personally certain that religion is a spandrel and if somebody is demonstrating evolutionary adaptivity in the modern times, I just point out that this is no proof with regard to pre-history. (And in doing that, you just sidestepped those many, clearly fertility-related female figurines – which are widespread and much, much older than 5000 years! How do these fit into the idea of a non-fertile spandrel?)

In contrast, Darwin defined religiosity in his “Descent of Man” as “belief in supernatural agents” and assumed very early beginnings in brain-based animism (here following Hume’s “Natural History of Religion”). He even did some comparisons with animals, especially dogs. And he assumed that the believed surveillance of supernaturals corresponded to changing behaviors, higher in-group loyalty and, thus, evolutionary success – as do many psychologists and sociologists today.

Just take one of the many examples of Sarah Hrdy: The belief in Chimerism. If people believed that children had more than one father, or if they believed that children were reborn ancestors, higher readiness to alloparental care would be the outcome. In fact, it IS among historic and contemporary hunters and gatherers!

But if we would assume that religiosity started as a “spandrel” (or an exaptation?), we would have to explain how it “got” the reproductive advantages we are observing today. To me, it seems to be more parsimonious to probe whether the observable effects of today could reach into the past than to decree that any contemporary effect should be ruled out from the start for the sake of an indirect route.

Cris:  Nice points.  I am not a Kantian so do not make a priori assumptions about anything, including spandrels or exaptations.  Increased fertility resulting from modern religions does not demonstrate adaptiveness.  It simply means that people who practice modern religions have more children.  As I stated earlier, evolution is not simply the product of increased fertility.

Evolution, in the classic sense, throws up variations (through random mutations) which can subsequently be targeted by selection, with the result being increased survival/reproduction directly related to the variation that confers a fitness advantage.  The usual result of this process is physical and/or behavioral change.

With this in mind, another step must be taken for your analysis to be convincing.  Don’t you need to demonstrate that the increased fertility is having genomic or phenotypic effects?  Given that culture over the last 5,000 years has substantially altered human mortality profiles, and dramatically diminished mortality rates, selection has been severely muted.  I fail to see what effect — if any — all this religiously increased fertility is having on genomes or phenotypes or behaviors.  More people means more variation, but when culture shields people from mortality selection, all we get is lots and lots of genetic variation (i.e., genetic noise) with nothing being fixed.  And without fixation or a selective sweep, there is no evolution.

Thus, I think the null hypothesis for evolutionary explanations should be that before 10,000 years ago, the primary driver of change in humans was biological evolution and that after 10,000 years ago (post Neolithic Revolution) the primary driver of change in humans is related to cultural forms, which include political systems, economic systems, legal systems, religious systems, technological systems, etc.  As is evident from the exponential population explosion caused by the Neolithic Revolution, selection — which at step one is about survival/death — was barely operating.  More and more people were surviving, and reproducing, and most of this had to do with one simple fact: the domestication of plants and animals (i.e., agriculture).

I also think it important to rely in the first instance on the data we have from 150,000 years ago to 5,000 years ago.  Do we have any evidence of “religion”?  No.  The venus or fertility figurines to which you point do not amount to religion.  Nor do burials or cave art.  These scanty items of evidence suggest shamanisms but not religions.  And there are fundamental differences between shamanisms on the one hand and religions on the other.  Until you can point me to shamanistic practices or traditions that bear directly on fertility and which resulted in increased birthrates, I will have to remain skeptical of the claim.

With respect to your final question — why, if supernaturalism is a spandrel, do we observe increased fertility among modern religious groups?  The answer, I think is fairly simple: religions do not exist in a cultural or social or historical vacuum.  Most religions encourage their members to marry and make babies for reasons of political, economic, and military security.

Over the last 5,000 years, small groups of people with peculiar religious ideas tend to disappear rather quickly.  Such groups tend to be crushed or conquered by larger groups.  To avoid this dismal fate, these small groups encourage reproduction.  They may make more babies, but I fail to see how this amounts to evolution.

• A generalized belief in higher powers, which may be gods, spirits, or other forces;

• A spiritualized reverence for nature and everything of nature;

• A cosmology oriented horizontally rather than vertically;

• A cyclic notion of time and perpetual renewal; and

• A belief array that includes animism, ritualism, totemism and shamanism.

Because humans have been foragers for the vast majority of their time on earth, understanding the supernatural beliefs and practices of hunter-gatherers is essential to any genealogy of religion.  This Category will examine those beliefs as part of a larger effort to trace the history of religion.