Offspring Human Fertility Behavior in Biodemographic Perspective (2003) / Chapter Skim
Currently Skimming:
11. Evolutionary Biology and Rational Choice in Models of Fertility
11. Evolutionary Biology and Rational Choice in Models of Fertility
Pages 322-338
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 322... ...
Considerable effort has been put into fitting the observed empirical patterns into economic and evolutionary theoretical perspectives, with some important successes. One of the most important features of these analyses in both economic and evolutionary approaches has been the recognition that decreased fertility is almost universally associated with increased investments 322
|
From page 323... ...
Quality-quantity trade-offs have been central to both economic and evolutionary models of fertility and arguably offer the most plausible way for reconciling both types of models with the observed empirical patterns. This chapter discusses the intersection between rational choice models of fertility especially models developed by economists and evolutionary biology models of human fertility.
|
From page 324... ...
and are one area in which evolutionary models are potentially informative. One of the useful features of these types of models is that they can also incorporate issues of time allocation and the opportunity cost of children by assuming that child quality is produced using inputs of time and goods according to some production function: Q = Fq(Tqw, Tqh, Xq)
|
From page 325... ...
Labor market earnings of the husband and wife plus unearned income A are used to purchase the market inouts for children and nonchild consumption.
|
From page 326... ...
of quantity-quality trade-offs that we could observe substantial decreases in child quantity offset by large increases in child quality in response to increased productivity of parents in producing child quality. Labor Market Productivity and the Price of Children It is often remarked that children are much more expensive today than they were 100 years ago, an observation that in turn is often used to help explain why fertility is so low in today's high-income countries.
|
From page 327... ...
This could occur because wages do not adjust to the actual increase in productivity or simply because the increase in home productivity is as large as the increase in labor market productivity.2 A woman will work in the labor market if and only if her labor earnings are worth more to the couple than the foregone productivity of her time at home. Increased schooling will increase the probability that a woman works in the labor market if that schooling causes a larger increase in her market wage than in her home productivity.
|
From page 328... ...
On the one hand is the race between home productivity and labor market productivity, driving the extent to which better-educated women are pulled into the labor force by higher wages. On the other hand is the adjustment in child quality and child quantity that results from the effects of schooling on home productivity.
|
From page 329... ...
_ Q ~ 3 . _ South Africa Brazil 74 1 o 329 l 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Years of schooling FIGURE 11-1 Number of live births by years of schooling for married women, ages 45 to 54, in Brazil 1984, and for black South Africans, 1995-1998.
|
From page 330... ...
SOURCE: 1984 Brazil PNAD and 1995-1998 South Africa October Household Survey.
|
From page 331... ...
Although fertility falls relatively steeply with schooling in both Brazil and South Africa, there is surprisingly little effect of the first 8 years of schooling on the probability that women are employed in the labor market. Figure 112 plots the proportion of all women ages 35 to 44 that reported being employed in the previous 7 days by years of schooling.
|
From page 332... ...
Wages increase substantially over this range, without any corresponding increase in women's employment, additional evidence that there is some aspect of women's time allocation other than labor market activity to explain the link between education and fertility. As suggested in the theoretical discussion above, investments in child quality may be the margin in which education and time allocation interact with fertility.
|
From page 333... ...
Increases in women's schooling also lead to increased labor market productivity, as evidenced by the large rise in wages. In making labor supply decisions, however, women are faced with simultaneous increases in home productivity and labor market productivity.
|
From page 334... ...
writes that "complexities in either the ecological or social environment that result in increased effectiveness of parental investment should result in more investment, even at the expense of fertility itself." Low's discussion suggests that high eventual reproductive payoffs to trading off child quantity for child quality in the current generation might hold the promise of reconciling evolutionary models of fertility with the awkward empirical evidence of declining fertility in the face of rapidly rising incomes over time. Parents might find it optimal to reduce child quantity in favor of quality in their own offspring, with the payoff coming in the form of increased numbers of grandchildren born to their wellendowed children.
|
From page 335... ...
It might further be argued that the rational choice economic mode! is therefore better able to explain modern low fertility than is the evolutionary model, since the observed fertility behavior is consistent with standard economic models.
|
From page 336... ...
In the case of quantity-quality trade-offs, the focus of this paper, it is worth considering whether evolutionary biology can help inform the economic mode! laid out above.
|
From page 337... ...
This prediction can also be applied to the effects of increased productivity of parents, resulting for example from increased schooling. Empirical evidence from Brazil and South Africa suggests that the strong negative effect of mother's schooling on fertility is the result of a strong oualitv-ouantitv trade-off over the first 8 Years of schooling.
|
From page 338... ...
Lam, D., and K Anderson 2002 Women's schooling, fertility, and investments in children in South Africa.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.