The baby bust
The baby bust is a babysitter shortage that no celebrity pep talk can fill. Today a couple raises a child mostly alone, with grandparents far away and friends who rarely bring a meal. Humans are built to hold back on a baby whenever helpers go missing, because for most of our history a child raised without them often died.
Source: Baby Nudges: How Social Influences Shape Fertility Choices, ifstudies.org
Humans evolved to raise children with many hands. For most of human history fathers, grandmothers, older children and unrelated helpers carried, soothed and fed babies. The survey's best countries sit far below that: only around a third expect friends to pitch in, and in Japan just 4 percent expect a meal.
The wish survives the shortage while the commitment drops. In every country studied except Israel, people have fewer children than they say would make them happiest, the drive keeping the wish while reading too few helpers. The drive also tracks sex with a partner who will stay: kin once arranged most marriages and forager adults fed children for years, while today the mate search runs alone, a couple feeds a child from its own pay, and the survey asked only partnered people about intentions.
The report's numbers show where talk runs out. Parental urging goes with 30 percent higher intentions, yet supportive friends go with fewer children ever born, because help peaks at the first baby and fades, where forager children had helpers present for years. Standing once came from prestige among people who knew you, and better hunters had more children; today the admired model is a screen figure, in Japan with one child on average.
Both camps name stated reasons over the same drive. Pronatalists blame lost values and critics blame unequal chores, yet sermons made no detectable difference and housework division predicted nothing, since the drive reads hands and food. For most of human history others held, fed and soothed infants daily, and devout people, who expect far more help from friends, want bigger families.
What they say it is
They say
Gaps between desired and actual family size are a cultural messaging problem: if peers, parents and celebrities celebrated children more, young people would have the children they want.
"Ultimately, social influences matter for young people trying to have families."
Held by the report's authors and the Institute for Family Studies framing of the study.
What it really is
The baby bust is a babysitter shortage.
Which system wins
Every brain system that could explain this, oldest at the top. The bar is how well each one explains the source.
Oldest firstScore, out of 1
-
500million yrsConditional drive for children: the urge drops when the organism reads it cannot raise them
-
500million yrsWanting children is the first drive
-
500million yrsA child costs the energy budget more than it can carry
-
50-100million yrsParents chase status and children cost it
-
2-5million yrsReligion and group norms set family size
Why it wins. Conditional drive for children: the urge drops when the organism reads it cannot raise them explains 8 of the 13 details in the source and sits on reproduction. It also has the top score.
The 13 details and the scores as a table
- D1 The report is by IFS and the Wheatley Institute, pronatalist bodies funded by private donors.
- D2 Ultra-Orthodox women in New York average 7.5 children against 1.58 for college-educated white women in the same metro; Ohio Amish about 6.
- D3 Survey of 9,915 respondents in a dozen countries (4,721 Americans), a nonprobability online panel.
- D4 Believing friends would celebrate a new baby goes with 10 percent more desired children and 20 percent more intent.
- D5 Parental encouragement goes with 11 percent more desired children and 30 percent more intent.
- D6 Admiring a public figure with a bigger family goes with 14 percent more intent.
- D7 Believing people have a moral obligation to have children does not predict intent.
- D8 In every country but Israel, people have fewer children than they say would make them happiest.
- D9 Just over 20 percent of Americans expect a friend to bring a meal after a new baby; 4 percent in Japan, 6 percent in Korea.
- D10 Parents who see parenting as a big burden intend 9 percent fewer further children.
- D11 The authors infer that TV exposure to childless celebrities lowered Japanese fertility after the mid-1980s.
- D12 The most religious third have 9 percent more children.
- D13 Taken for granted: birth rates sit below replacement and many people say they do not want children.
| Reading | System | At stake | Details | Distance | Score |
|---|---|---|---|---|---|
| Conditional drive for children: the urge drops when the organism reads it cannot raise them | M14 | Reproduction | 8/13 | 2/3 | 0.65 |
| Wanting children is the first drive | M14 | Reproduction | 2/13 | 1/3 | 0.47 |
| Parents chase status and children cost it | M5 | Standing | 3/13 | 2/3 | 0.35 |
| A child costs the energy budget more than it can carry | M13 | Standing | 1/13 | 2/3 | 0.31 |
| Religion and group norms set family size | M11 | Standing | 3/13 | 1/3 | 0.30 |
Score = 0.571 x what is at stake (survival 1, reproduction 0.67, standing 0.33) + 0.286 x share of details explained + 0.143 x distance from the camp. Phylogenetic age adds no points; it orders the stack and settles near-ties.
So now what?
- Before a baby arrives, line up named people for regular help: who brings meals in the first weeks, who takes a standing weekly afternoon with the child.
- When choosing where to live, pick a place within easy reach of a grandparent, sibling or close friend who will help with a child week after week.
- Spend regular time in the homes of friends who are raising young children, so babies and the people caring for them are part of ordinary weeks.
If you take psychiatric medication: where no biomarker shows a physical disease, the goal is to come off it. Work on the real cause, most often your situation with other people, at the same time as a slow taper supervised by your doctor. Never stop suddenly: stopping some drugs at once is dangerous.
How do we know?
8 claims, 6 counterpoints
The wish for children is built in and conditional: mothers evolved to weigh whether help and food would let them carry a child through to independence, and to hold back when help read as missing.
E281 argued, not yet testedE402 argued, not yet testedE271 argued, not yet testedE22 argued, not yet testedE256 argued, not yet tested
For most of human history fathers, grandmothers, older children and unrelated helpers carried, soothed and fed babies, and others answered a large share of their cries.
EEA-CARE-01 tested many timesEEA-CARE-02 argued, not yet testedE271 argued, not yet testedE22 argued, not yet testedE700 tested onceE750 tested onceE701 tested onceE699 tested onceE749 tested many times
Forager adults produced more food than they ate and passed the surplus to children for many years, and large game was shared beyond the hunter's household.
E710 tested many timesE707 tested many timesE780 tested many times
Across forager societies about half of children died before age 15.
In forager bands standing came from prestige freely given, and where detailed records exist better hunters had more children.
EEA-SOC-10 contestedE689 tested many timesE770 tested many timesE731 tested many times
In most forager societies on record, parents or other kin arranged marriages.
Around a third of US, UK and Irish respondents expect friends to help with a new baby, only 4 percent of Japanese respondents expect meals from friends, and actual fertility is below the family size people say would make them happiest in every country studied except Israel.
Parental encouragement goes with 30 percent higher intentions, more supportive friends go with fewer children ever born, religious leaders' exhortations show no detectable effect, and the division of housework does not predict fertility.
What cuts against it
Some researchers dispute that humans are cooperative breeders and describe human reproduction as biocultural; a review found most natural-fertility studies do not support a grandmother effect, fathers improved child survival in only a third of studies, and in one forager group mothers still did about 69 percent of infant holding.
E703 contestedE704 contestedE382 tested many timesE749 tested many times
Calling low fertility a mismatch assumes genetic fitness is the measure; cultural transmission may reward behaviour that lowers it, and reading modern restraint as maladaptive is theoretical.
Modern policy evidence is mixed: childcare coverage and cash payments raised births in some places, while Korean programs did not reverse the decline and no economic or policy factor explained much of the US fall.
E823 contestedE812 contestedE813 tested onceE814 tested onceE832 contested
Frequent grandparental care went with a 66 versus 35 percent predicted chance of another birth in the Netherlands, but occasional care showed no significant effect, and this is a single modern sample.
The model that pronatal norms weaken when kin make up a smaller share of contacts is a model result, with a direct counterpoint from large personal network data.
Mate preferences and mating systems vary with local economies and populations.
Not in Cor yet
Among mobile foragers, a birth was met with food gifts, visits and help from campmates in the first weeks.
Ethnographic accounts of postpartum support in mobile forager bands (e.g. Hewlett and Lamb on Aka, Konner on !Kung)
Forager women with more helpers nearby had more children or closer-spaced births.
Page et al. or Sear and Mace style analysis of alloparental help and fertility in a mobile forager population
Grades are Cor's. Every id opens its Cor page.
Sources
- Baby Nudges: How Social Influences Shape Fertility Choices. ifstudies.org. The source decoded here.
- Apostolou (2007). Sexual selection under parental choice: the role of parents in the evolution of human mating.
- Bauernschuster et al. (2015). Children of a (policy) revolution: the introduction of universal child care and its effect on fertility.
- Crittenden & Marlowe (2008). Allomaternal care among the Hadza of Tanzania.
- Garfield et al. (2019). The evolutionary anthropology of political leadership.
- Gurven (2004). To give and to give not: The behavioral ecology of human food transfers.
- Hewlett et al. (1998). Culture and early infancy among central African foragers and farmers.
- Hrdy (1999). Mother Nature: A History of Mothers, Infants, and Natural Selection.
- Hrdy (2009). Mothers and Others: The Evolutionary Origins of Mutual Understanding.
- Jaeggi & Gurven (2013). Natural cooperators: Food sharing in humans and other primates.
- Kaplan et al. (2000). A theory of human life history evolution: Diet, intelligence, and longevity.
- Kaptijn et al. (2010). How grandparents matter: support for the cooperative breeding hypothesis in a contemporary Dutch population.
- Kearney et al. (2022). The puzzle of falling US birth rates since the Great Recession.
- Konner (2005). Hunter-gatherer infancy and childhood: The !Kung and others.
- Kramer (2010). Cooperative breeding and its significance to the demographic success of humans.
- Kruger & Konner (2010). Who responds to crying? Maternal and allocaregiver responses to infant crying among !Kung.
- Lee & Choi (2015). Lowest-low fertility and policy responses in South Korea.
- Milligan (2005). Subsidizing the stork: new evidence on tax incentives and fertility.
- Newson et al. (2007). Influences on communication about reproduction: the cultural evolution of low fertility.
- Panksepp (1998). Affective Neuroscience: The Foundations of Human and Animal Emotions.
- Richerson & Boyd (2005). Not by Genes Alone: How Culture Transformed Human Evolution.
- Scelza et al. (2020). High rate of extrapair paternity in a human population demonstrates diversity in human reproductive strategies.
- Sear & Mace (2008). Who keeps children alive? A review of the effects of kin on child survival.
- Smith (2004). Why do good hunters have higher reproductive success?.
- Speder et al. (2019). Cash support vs. tax incentives: the differential impact of policy interventions on third births in contemporary Hungary.
- Tronick et al. (1987). Multiple caretaking of Efe (Pygmy) infants.
- Volk & Atkinson (2013). Infant and child death in the human environment of evolutionary adaptation.
- von Rueden & Jaeggi (2016). Men's status and reproductive success in 33 nonindustrial societies: Effects of subsistence, marriage system, and reciprocal exchange.
- Walker et al. (2011). Evolutionary history of hunter-gatherer marriage practices.
- Wood & Eagly (2002). A cross-cultural analysis of the behavior of women and men: Implications for the origins of sex differences.