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Abstract The adoption of contraception often coincides with market integration and has transformative effects on fertility behavior. Yet many parents in small-scale societies make decisions about whether and when to adopt family planning in an environment where the payoffs to have smaller families are uncertain. Here we track the fertility of Maya women across 90 years, spanning the transition from natural to contracepting fertility. We first situate the uncertainty in which fertility decisions are made and model how childbearing behaviors respond. We find that contraception, a key factor in cultural transmission models of fertility decline, initially has little effect on family size as women appear to hedge their bets and adopt fertility control only at the end of their reproductive careers. Family planning is, however, associated with the spread of lower fertility in later cohorts. Distinguishing influences on the origin versus spread of a behaviour provides valuable insight into causal factors shaping individual and normative changes in fertility.
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Uncertainty in a globalizing world. Livelihood and fertility variance increases in response to rapid change
Abstract ObjectivesThe extreme condition that we address in this special issue is how people adapt to rapid change, which in this case study is instigated by globalization and the process of market integration. Although market integration has been underway for centuries in some parts of the world, it often occurs precipitously in small‐scale societies, initiating an abrupt break with traditional ways of life and fostering a keen sense of uncertainty. MethodsUsing cross sections from 30‐years of data collected in a Yucatec Maya subsistence farming community, we test the expectation that when payoffs to pursue new livelihood and reproductive options are uncertain, variance in social, economic, and reproductive traits will increase in the population. Our data span the transition from subsistence farming to a mixed economy, and bridge the transition from natural to contracepting fertility. Exposure to globalizing and market forces occurred when a paved road was built in the early 2000s. ResultsWe find that livelihood traits (a household's primary economic strategy, amount of land under cultivation, amount of maize and honey sold), become more variable as new, but uncertain options become available. Variance in levels of education and family size likewise immediately increase following the road, but show signs of settling back down a decade later. Rather than replacing one way of life with another, Maya farmers conservatively adopt some new elements (family planning, wage labor), until the tradeoffs to commit to smaller families and the labor market become clearer. ConclusionOur findings highlight that in rapidly changing environments when the payoffs to assimilate new options are uncertain, some households and individuals intensify what they know best, while others adopt new opportunities, driving variance up in the population.
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- Award ID(s):
- 2051264
- PAR ID:
- 10481722
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- American Journal of Human Biology
- ISSN:
- 1042-0533
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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