Rogoff, 1990; Vygotsky, 1978, 1986). Finally, high productivity, generosity, and social effort by parents generate not only social capital for themselves but also future material benefits for offspring—access to scarce social and material resources (e.g., marriage opportunities or food, respectively) that may serve as a hedge against premature parental illness or death.

Implications for Life History

How, then, should sociality and multitasking be counted in life history terms? Existing theory should be pushed to cope with these realities of human reproductive behavior. Sociality raises productivity through its impact on intake and maintenance via the pathways described above. It represents a major overlooked approach to meeting other maintenance and reproductive demands. Though sociality exacts real costs, it yields tangible benefits. Social effort accordingly represents an important arena for the allocation of trade-offs. Similarly, multitasking represents a challenging phenomenon for parsing allocation in behavior analysis and adaptationist logic. The ubiquity of multitasking relating to reproduction and involving social life indicates that its omission may limit the capacity of current behavioral ecology and life history theory to contribute to the understanding of human reproductive behavior.

The importance of social relationships, their role in fertility behavior, and their value in determining long-term offspring viability are not unique to humans. The data on baboons presented by Altmann and Alberts in this volume provide compelling nuanced evidence of this. Reproductive effort comprises complex social strategizing, not just copulating and giving birth, and the insight that such strategic capacities are both significant in humans and not unique to them should broaden our view of the determinants of fertility schedules. Efforts directed at social relationships, including relationships with group members who are neither coparents nor primary kin, yield costs and benefits over time that determine mating and parenting success. Therefore, from a life history perspective, strategies to establish, maintain, and enhance social relationships are essential components of reproductive effort.

EPIGENESIS AND REARING ENVIRONMENTS

Epigenesis in Human Reproduction

As noted above, reproduction faces an information problem: how the blueprint for a fully functional adult organism can be conveyed through the union of two parent cells. It was suggested that biocultural inheritance was an aspect of the solution. This is part of the broader process of epigenesis,



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement