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What Small Scale Societies Tell Us About Our Own Child-Bearing Decisions
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Culture
Image credit: Kalahari San
Lesley Newson
Lesley Newson
is a honorary post-doc at University of California, Davis. She studies the cultural evolutionary process known as “modernization” which most human populations are now experiencing.

There is no shortage of information on how we reproduce. Sexual behaviour, pregnancy and child-rearing are all hot topics in all our media. But the coverage is almost always about how we do it – “we” who live in modern, usually Western societies. How relevant is it to look at what we do today if we want to learn about human reproductive behaviour?

Okay, modern Westerners are human too, of course, but we’re only a fraction of the people living on Earth today. And, if you think about the thousands of generations of humans who lived and died before the industrial revolution, our specific ways of doing things seem even less relevant to the big picture of human behaviour. Modern culture has profoundly influenced our lives and strongly influenced our reproductive behaviour. (Think: contraception, drugs to cure sexually transmitted diseases, on-line pornography, internet dating, vaccination, compulsory schooling and laws against hitting naughty children.)

To test Darwinian ideas about human behaviour we need to study people in a wide range of cultures, including cultures which Westerners used to describe as “primitive”, “barbarous”, “uncivilized”, or “undeveloped”. Nowadays anthropologists tend to call them “small-scale societies”, which is more descriptive and less insulting. Reproduction in these societies seems to more closely match Darwinian predictions than that of modern people who have vast resources and very few offspring. Studies of small-scale societies are essential for developing and testing evolutionary theories of human behaviour because their members live in conditions much closer to those which humans experienced for most of our evolutionary history. Small scale societies have culture too, of course, and looking at their behaviour in light of their cultural environments can give us a more general view of human reproduction.

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Unfortunately, there are very few truly small-scale societies left. Nowadays, even many nomadic hunter-gather groups have become dependent on their mobile phones. But we can draw on the reports of historians and of anthropologists who began studying peoples living in remote parts of the world well over a century ago.

In the foraging, herding and subsistence farming communities in which humans lived for most of our evolutionary history, people got all their social information (information from other people) by observing and talking to their family and other members of their community. Members of small scale societies have detailed knowledge of the environments they live in and the expertise needed for exploiting them. And their lives were intricately interwoven with the lives of the people in the family and community they were part of. Their interaction with strangers was limited and so was their knowledge of the wider world, although they may have shared plenty of stories about the wider world.

Our ancestors lived in small-scale communities much more recently than one might imagine from a casual reading of history. It’s true that ancient cities like Babylon and Rome were “large-scale” in that elites and city-dwellers had large complex social and economic networks and in some cases written texts. But the population of these cities was tiny compared to today’s cities. And they didn’t last long. Ancient civilizations, dynasties and empires rose and fell without affecting the lives of more than a small proportion of the humans alive at the time. Most of our ancestors lived in small rural communities. They may have traded with people from towns and cities but they didn’t have much to do with them. In his survey of England’s population at the end of the 17th century Gregory King estimated that 80 per cent of the people lived in small villages and hamlets. England was poised to begin its industrial revolution; her wealth, infrastructure and literacy were growing rapidly but in 1700, few English towns, apart from London had a population that reached ten thousand.

Information about the opinions and customs of people living in this time can be gleaned from diaries, letters and other written materials and many places had officials who assiduously kept records of the births, deaths and marriages. In Europe, some records go back as far as the 1500s and supply the basic details of the lives of the rural population as well as people living in market towns and cities. We also have a great deal of information about small scale societies outside Europe, some from historical records and archives and some from anthropological studies of small-scale societies that continued to exist into the twentieth and twenty-first centuries.

The findings of historical and anthropological studies have revealed so much variation in the reproductive behaviour of humans that it hardly makes sense to talk about “human reproductive behaviour”.   But they also reveal three important similarities:

  1. Every human population has beliefs and rules about reproduction that influence almost every aspect of their lives. Within each community people have more or less the same beliefs so, in general, members of the same cultural group have similar behaviour.

There are often large differences between populations, however. For example, many cultures believe a woman should limit herself to sex with a single man so that the paternity of her children can be certain but this belief is far from universal. Several tribal cultures in the South American lowlands believe (or at least they did until recently) that a child is conceived from the build-up of semen from several men. It’s thought best for women to have several sexual partners because babies with more fathers are likely to be stronger. When a woman gets pregnant, her sexual partners and their families are expected to work together to help her feed and care for their young relative (Walker, Flinn et al. 2010). Other examples are provided by beliefs about gaining sexual pleasure in ways that don’t result in the conception of offspring. Same-sex sexuality is considered wrong in many cultures but many see it as a normal, even essential, part of life (Kirkpatrick 2000). Beliefs change over time too. Masturbation was considered sinful in 19th England but 200 years earlier people seem to have thought it normal and necessary (Hitchcock 1997).

Beliefs about what children need and how they should behave also vary widely from population to population and from time to time. For example, it may seem obvious that human breast milk is the best food for human babies but some farming communities in central Europe appear to have had a centuries long tradition of not breast feeding at all, a tradition that lasted until the 20th century (Kintner 1985). Mothers in Upper Bavaria who breastfed their infants were subject to taunts and ridicule from neighbours and threats from their husband. Babies were instead fed “pap”, a thick paste made by boiling together flour, water and raw cows’ milk. Scripts of Medieval Christmas plays from the area depict Mary making pap for the newborn baby Jesus.

  1. All cultures believe that human mothers need a great deal of help raising children. It’s easy to see why this is the case; any population that didn’t accept this obvious fact would soon become extinct. A single parent (male or female) can’t possibly provide the all the nourishment, care and protection that a human baby needs (Hrdy 2009). Our babies need to grow a human-sized brain and to do this they must be supplied with much more energy than similar-sized mammals with a smaller brain. The largeness of its brain also means that a human baby has to be born at an earlier stage of development than the babies of other apes. A baby human must exit the womb while its head is still small enough fit through the opening in its mother’s pelvis. Newborn humans are therefore much less developed than newborn chimps so they’re weaker and need more care. From the moment a baby chimp takes its first breath, it’s able to cling on to its mothers’ hair and help itself to milk from her teats. This leaves the mother chimp’s hands free for climbing and getting food. Being clingy is essential for chimps because other members of a chimpanzee troop are not just unreliable helpers; they have been observed to snatch away babies and kill them (Pusey, Murray et al. 2007).   Chimps are weaned and more or less independent by the age of five and by this time the mother is usually carrying her next baby.

All cultures may recognize that mothers need help but that is where the agreement ends. Beliefs about the kinds of help mothers need and who should supply it vary widely. In modern cultures, people are paid to care for and educate other people’s children and fathers are expected to do some of the hands-on care. The role played by human fathers varies a lot. In many small-scale societies fathers do little direct caring for children but help by providing other necessities such as food, security, and status in the community. The father’s female kin may spend more time with his baby than he does. In a few cultures, the mother’s relatives provide almost all the help and the baby’s father provides nothing more than his genes. And in many cultures, older children provide much of the hands-on care of their younger siblings, cousins, nieces and nephews. The amount and kind of work that children do (child-care and other work) varies considerably culture-to-culture (Hrdy 1999; Kramer 2005).

  1. All cultures practice birth control. Only modern societies have contraceptive technology but all societies have customs and/or rules that serve to regulate conceptions.

For example, when Nick Blurton-Jones (1987) studied nomadic !Kung hunter-gatherers in the deserts of South Africa in the 1970s and 80s, he found that most women had a gap between their births of about four years. He also found women who left this a gap of this length had greater reproductive success. Four years seemed to be the ideal spacing for producing the most children while giving each child a good chance of survival. The ability of !Kung women to achieve this spacing probably had a lot to do with their custom of breastfeeding babies until the age of four. Breastfeeding inhibits ovulation, especially in women who are lean, as these women were.

Rules about when it’s appropriate for a woman to have sexual intercourse are important regulators of conception. Some cultures discourage a couple from having sex until their youngest child is weaned, thus making it more likely that babies are born far enough apart that mothers retain their strength and babies get adequate care. A rule that only married couples should have sex reduces the chances of a woman having to endure the risks and strain of pregnancy and birth when she doesn’t have the resources or support necessary to give her child a reasonable chance of reaching adulthood. The European records of birth and marriages suggest that most people obeyed such a rule until the mid-twentieth century (Coale and Treadway 1986). Almost all babies were born in wedlock, although in some regions it was common for a woman’s first child to be conceived before her marriage. Humans can experience sexual pleasure without performing the kinds of mating behaviours that lead to conception and a considerable body of historical evidence from many cultures reveals that unmarried men and woman were not necessarily abstaining from sex, just the kind of sex that leads to pregnancy (e.g., Hitchcock 1997; Kirkpatrick 2000).

The records also suggest that until the late 19th century, once Europeans got married, most of them tried to raise as many children as they could. This is certainly the case with Charles and Emma Darwin. They married in 1839 when they were both 30 and Emma went on give birth to 10 children, seven of which survived to adulthood. The Darwins were wealthy with a large house in the country but many couples of more modest means also produced many children. Meanwhile, a substantial proportion of the population decided, like Charles Darwin’s older brother, Ras, remained unmarried.

When the reproductive behaviour of humans is analysed from a Darwinian perspective, a fourth important consistency is observed. By and large, people who live in small-scale societies or who belong to populations that are at an early stage of economic development behave as if they’re striving to maximize their fitness (e.g., Cronk 1991; Low 1993). They aren’t necessarily trying to have as many children as possible themselves, but they’re behaving as if they want to see their genes get reproduced. People who have no children usually contribute to their genetic fitness by helping their relatives and, if possible (if harvests improve or more work becomes available), they usually get married and have their own children. One of the pieces of evidence that demonstrates this is a careful study of births, deaths and marriages in England from 1541 to 1871. The records reveal that during more prosperous times more people got married and more babies were born (Wrigley and Schofield 1981; Coale 1986).

But then it changed. The child-bearing decisions of people who live in modern cultures show no evidence of any effort to maximize fitness (Vining 1986; Kaplan, Lancaster et al. 1995; Borgerhoff Mulder 1998; Goodman, Koupil et al. 2012). Most people in modern societies can afford to raise many children but they choose not to. Many don’t have any children at all.

The change from striving for fitness to not striving for fitness happens very quickly; in some populations it happens in a generation or less. Researchers have learned a great deal about this behavioural change, but not its cause. It’s a mystery that Darwinists need to solve. See: Why do Modern People Have so Few Children.

Literature cited

Blurton, Jones, et al. (1987). Bushman birth spacing: Direct tests of some simple predictions. Ethology and Sociobiology 8:183-203.

Borgerhoff Mulder, M. (1998). “The demographic transition: Are we any closer to an evolutionary explanation?” Trends in Ecology & Evolution 13: 266-270.

Coale, A. J. (1986). The decline of fertility in Europe as a chapter in demographic history. The Decline of Fertility in Europe. A. J. Coale and S. C. Watkins. Princeton, N.J., Princeton University Press: xxii, 484 , [412] folded leaves of plates.

Coale, A. J. and R. Treadway (1986). A summary of the changing distribution of overall fertility, marital fertility, and the proportion married in the provinces of Europe. The Decline of Fertility in Europe. A. J. Coale and S. C. Watkins. Princeton, NJ, Princeton University Press: 31-181.

Cronk, L. (1991). “Human behavioral ecology.” Annual Review of Anthropology 20: 25-53.

Goodman, A., I. Koupil, et al. (2012). “Low fertility increases descendant socioeconomic position but reduces long-term fitness in a modern post-industrial society.” Proceedings of the Royal Society B 29 August 2012.

Hitchcock, T. (1997). English Sexualities. London, MacMillan.

Hrdy, S. B. (1999). Mother Nature: A History of Mothers, Infants and Natural Selection. New York, Pantheon/Chatto & Windus.

Hrdy, S. B. (2009). Mothers and Others: The evolutionary origins of mutual understanding. Cambridge, MA, Harvard University Press.

Kaplan, H., J. B. Lancaster, et al. (1995). “Does observed fertility maximize fitness among New Mexico men? A test of an optimality model and a new theory of parental investment in the embodied capital of offspring.” Human Nature 6: 325-360.

Kintner, H. J. (1985). “Trends and regional differences in breastfeeding in Germany from 1871 to 1937.” Journal of Family History 10(2): 163-182.

Kirkpatrick, R. C. (2000). “The evolution of human homosexual behavior.” Current Anthropology 41(3): 385-398.

Kramer, K. L. (2005). “Children’s help and the pace of reproduction: Cooperative breeding in humans.” Evolutionary Anthropology 14(6): 224-237.

Low, B. S. (1993). “Ecological demography: A synthetic focus in evolutionary anthropology.” Evolutionary Anthropology 1: 177-187.

Pusey, A., C. Murray, et al. (2007). “Severe aggression among female Pan troglodytes schweinfurthii at Gombe National Park, Tanzania.” International Journal of Primatology.

Vining, D. (1986). “Social versus reproductive success: The Central Theoretical Problem of human sociobiology.” Behavioral and Brain Sciences 9: 167-216.

Walker, R. S., M. V. Flinn, et al. (2010). “Evolutionary history of partible paternity in lowland South America.” Proceedings of the National Academy of Sciences 107(45): 19195-19200.

Wrigley, E. and R. S. Schofield (1981). The Population History of England, 1541-1871. Cambridge:Harvard Univ. Press.

15 Comments

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15 Comments

  1. Juan Alfonso says:

    Great article, Leslie!

    The example of the upper Bavarian mothers who were encouraged NOT to breast feed their babies and feed them instead with flour and cow´s milk is awesome! Harvey Karp (in “The happiest baby on the block”) says that cow´s milk is very “strong” for newborn: it gives them baby colics. Goat´s milk, he says, is better. And mother´s milk gives them almost no colics at all.

    Then, why did upper bavarians adopted such a potentially harmful tradition? Well, this seems to me like a great example of gene-culture co-evolution! This tradition, if held across many generations, would have helped Natural Selection to act on and select for both cow´s milk lactose-tolerant children and gluten-tolerant children. To me this would make perfect sense! Such a tradition (or Boyd´s and Richerson “Cultural Variant”) would facilitate the genetic evolution of individuals increasingly adapted to their environment: a diet based on cow´s milk and grain. This could be a case of genes and culture working side by side to quickly adapt a population to its niche.

    In my opinion the “enigma” here is that, from an individual-interest point of view, mothers who took more care of their babies (breast feeding them) would probably enhance their fitness, at least in the short-term; Perhaps these “selfish” mothers could kind of free-ride (as modern parents who refuse to vaccinate their children do) on a population trend, hoping that their children would mate with sexual partners that would do have the advantageous tolerance genes and pass them to their offspring. To solve this free-riding issue Cultural Evolution would need to find the ways to inforce the tradition: ridicule and taunting could account for such a mechanism since reputational position is extremely important when living in a small-scale group.

    Lactose-tolerance is possibly the most evident living example of gene-culture co-evolution. Could this be one explanation to how it evolved in such a short time?… Could this be an instance of cultural group selection?…

    • Lesley Newson says:

      Juan, It may be that the people in Bavaria thought they were selecting babies that would be able to drink cow’s milk but it wouldn’t be because of lactose tolerance. All mammal babies have to be able to break down lactose or they wouldn’t be able to properly digest their mother’s milk. Most cases, however, the gene for making lactase (the enzyme that does the break down) is turned off once they are weaned and no longer need to survive on milk. Members of cultures that obtain part of their food through dairying have a mutation that stops the gene turning off so they continue to secrete lactase.

      I agree with you that the presence of lactose tolerance in dairying populations is a good example of gene-culture co-evolution. It shows how quickly genetic change can occur when culture provides strong selection.
      In the case of the culture of not breast-feeding in Bavaria, I always think of it as an example of how culture can get it wrong, providing it’s members with rules that are less than ideal and as long as populations are relatively isolated, they can persist.
      It might have been that some women who found breast-feeding difficult were particularly prestigious and influential in the community and they enforced the non-breastfeeding idea. As a result, the mortality of their infants was no higher than that of women who would have been better breastfeeders and inability to breastfeed was not selected against in that population.

      • Juan Alfonso says:

        Yes, you are right, of course. It is the tolerance to cow´s milk not to lactase in general what could be selected through this process. May be you are right about “culture getting it wrong” in this case but I find it unlikely since it is a cultural variant that is mainly transmitted vertically. Vertically transmitted cultural variants tend to be similar to genes in the sense that it is difficult for harmful genes to linger in the gene pool… unless, as you say, they constitute a conspicuous handicap: a signal of prestige. In that case NOT breastfeeding would be a signal of status since it would harm the babies, and only the most healthy babies would be ok with that.
        On the other hand there is the possibility that the long-term advantages of “forcing” babies into feeding on cow´s milk are higher than the costs. Perhaps babies who better tolerate cow´s milk will turn into adults who are healthier living with a diet based on cow´s milk. Perhaps children who can´t tolerate cow´s milk and die are the ones would turn into unhealthy and less productive adults if they were breastfed instead. And that could be an opportunity cost higher than the cost in the form of increased infant mortality.
        May be it is more efficient to force babies into cow´s milk: those who die are the ones that would have turn into unhealthy adults. This would be a direct sieve or selective force in just one generation, but during many generations genes for babies who can tolerate cow´s milk (and that would turn into healthy cow´s milk drinking adults) would vastly predominate.

  2. Rosemary Hopcroft says:

    Leslie,
    You have heard me say this before but I will say it again. Just because fertility rates are low (and even below replacement for the society as a whole) does not mean that people are no longer maximizing fitness in modern environments.
    As in previous societies, the variance in reproductive success among women is lower than among men. In modern societies, most women have two or fewer children, but some men have more and some men (low status men) have none. Also as in previous societies, the highest fertility is found among high status males and among low status females (see Fieder and Huber 2007 -Sweden; Nettle and Pollet 2008-U.K; Hopcroft 2006, 2015- U.S.; Lappegard and Ronsen 2013-Norway).
    These familiar patterns suggest that people are doing what they always have, but in modern environments that effectively discourage fertility.

    • Lesley Newson says:

      Rosemary, I’m not convinced of the arguments used to justify the re-definition of “fitness” that you, Dan and others use to justify your declaration that people in modern societies are continuing to maximize fitness.

      Perhaps the difference lies in the way that we think about environment and behaviour. You see the norms (rules, customs, beliefs etc) that discourage modern people from having many children to be part of the environment. I see norms as being the product of human behaviour. Unlike other animals, human groups make and follow norms but as individuals we have choices about these norms – what norms to invent, which norms to follow, which to teach, which to enforce, which to deride, which to insist that our children obey etc. Faced with the same array of options, individual make different choices no doubt due to differences in experience and genetic differences. The change of norms is driven by changes in the choices people make.

      I am interested in the observation that members of small scale societies and societies that have just begun to modernize continue to follow and promote norms that encourage the effective conversion of resources. But then, after modernization has progressed a little, these norms change and most people begin to have low fertility. Individual differences still remain, however. I am not sure that the patterns in these individual differences are that familiar. It would be interesting to look at people who choose to have no children because if genes influence this choice their presence in the human gene pool will gradually diminish. Even more interesting will be to look at people who have many children. Any genetic or cultural variants associated with making the choice which resulted in high fertility will have higher frequency in the future.

  3. Denise Cummins says:

    Excellent essay! Thanks for posting this.

  4. Rosemary Hopcroft says:

    Lesley,

    Yes I do see the see the “norms (rules, customs, beliefs etc) that discourage modern people from having many children to be part of the environment.” But those norms are a response to an environment where for women, for example, it is very hard to maintain a regular job with having children (unless you are very rich and can afford round the clock help), and where women having jobs is necessary for families to maintain a decent standard of living in a modern industrial society (albeit a very high standard of living by historical standards).
    Fertility changes when opportunities change – for children and for women – and then the norms change. Scratch a norm and watch an interest bleed, is what I see.
    -Rosemary

    • Lesley Newson says:

      Aren’t the opportunities and attitudes to the various opportunities also products of human behaviour? And I agree with you that interest and competition is involved but it isn’t just people wanting to do the best for their family. Women working in the textile industry towns in England in the 19th century still had large families, not quite as large as the women in the coal mining villages, where their was no work for women other than being the wives of coal miners.

      Nowadays, having enough money for round the clock care doesn’t cause women to have many children. Bill and Melinda Gates only have 2, as I understand it. They follow modern norms. Meanwhile, members of Old Order Anabaptist (Amish, Mennonite and Hutterite) communities don’t follow modern norms. They isolate themselves from modern society are reasonably prosperous, have very low infant mortality AND produce 8 or more children.

      We are in England at the moment where there is controversy at the moment over benefits. Many working couples resent the fact that non-working single mothers can receive a higher household income because they have many children. The recently elected Conservative government has made changes which, they hope, will reduce this. On a news programme we watched a woman who will be affected by this was interviewed. She was a very pretty blonde woman who looked to be in her late 30s. She had eight children by various fathers who looked well and happy. She said that she understood that she had made some decisions that some people disapprove of but didn’t see why her children had to suffer for this.

      The point is though, that there are very few women like this, even in countries where the government benefits for women with children are more generous than England’s. Most people follow the norms.

  5. Rosemary Hopcroft says:

    First, Bill and Melinda Gates have three children, which is more than the average American family. And, yes, I agree the opportunities and attitudes to various opportunities are also products of human behavior. People are a social species and they respond to the opportunities available to them and to the attitudes of their social group. Think of the opportunities available to the eight children of the woman you mention. It will be difficult for any of them to fit in socially with the children of other families due to lack of money and lack of their own skills, training and cultural capital. The latter take the time and effort of parents, and their single mother will be unable to devote much time and effort to each of her children. Likely these children will not do well in school and will not have good economic opportunities as a result. Most mothers in modern societies are not willing to do this to their children, and so don’t have so many children.

    • Lesley Newson says:

      OK so the Gates have 3 children is That is still a very small number compared to what humans are capable of.

      On what do you base your suggestion that the eight children of the single mother won’t do well? Even if some of them don’t excel at school, some of them will probably do OK. Certainly their mother seemed articulate and very switched on. And even if they don’t get a highly paid job, they will likely still be able to afford to have some children. A woman who has 8 children is likely to have at least 10 grandchildren. A women who has 2 children is unlikely to have more than 5 grandchildren.

      • Rosemary Hopcroft says:

        Statistically, children of low SES, single mothers don’t do as well (educationally and economically) as children of higher SES, intact families in modern societies. Of course, that doesn’t mean the children of this particular women won’t do well. But it will be harder for these kids than for kids in smaller families. We evolved to love and care for our children, and this includes wanting to help ensure their success in life. That is why most women in modern societies don’t want to have lots of children.

  6. Guillaume Combot says:

    I saved many many hours of research by reading your great article. It’s very clear, easy to read, and full of sources, thank you very much Lesley!

  7. David Milgrim says:

    Thanks, Lesley, for another interesting article.

    Reading this and the comments makes me wonder about the type of research that might shed light on this. I imagine much has been done, but I am curious about the variance of family sizes within a culture. I know people who have always wanted a big family and others who wanted no family. I wonder what their reasons and lifestyles are. Variation within a culture could shed light on variation between cultures since it might offer a control over some of the factors. I imagine that within a large modern culture we find the functional equivalent of many individually chosen, but distinct, subcultures.

    There is also the question of why people change their minds about this during their life.

    Finding correlations to other factors is, I suppose, one clue. I would wonder about correlations to systems of meaning and personal value and worth. This is a hard one to measure. For example, I would wonder how common it is for woman who have high level, high responsibility jobs to also have large families.

    It is interesting about the small societies on the verge of modernization who quickly have a drop in family size (if I read this right). I wonder what they report their own reasons are. I wonder what they are busy with. I wonder if societies undergoing any type of rapid cultural change tend toward lower rates.

    It seems like a giant subject that would need lots of correlation studies to begin to detect patterns. My from the hip ideas (shared in the comments of your previous article) may be right or not. I also wonder how you might apply the results to policy or new social memes.

    • Lesley Newson says:

      Hi David,
      I agree that it would be interesting to look at variation in fertility. Quite a bit of research by human behavioural ecologists has suggested that in small scale societies higher fertility is associated with increased control of resources – whether it be better hunters in HG societies or better farmers or craftsmen in early modern societies – just evolutionary theory would suggest.

      In Modern societies, I think that it is important not to simply look at people who have had 3 children versus one child because both these numbers are far lower than the fertility that healthy well-nourished humans can achieve. I am interested in the people who are having 8+ children. What is it about them that causes them to fail to follow the modern small family norm. Old Order Anabaptists are interesting although one might ask if they are truly part of modern society.

      A lot of research has also been done (mostly in the 1970s, 80s, and 90s) about factors associated with fertility decline in developing countries. I wrote a review paper you might be interested it (Newson, L., T. Postmes, S. E. G. Lea, and P. Webley. “Why Are Modern Families Small? Toward an Evolutionary and Cultural Explanation for the Demographic Transition.” Personality And Social Psychology Review 9, no. 4 (2005): 360-75.).