The rising influence of `Human Nature’ and renewed interest in middle childhood

Members of the Evolutionary Anthropology Society regularly read and contribute to the journal, Human Nature: An Interdisciplinary Biosocial Perspective (HN). HN has a special relationship with EAS: “As a general rule, each year the journal publishes one or two special issues based on an [EAS] organized session … as well as the Best Student and Best New Investigator Award papers,” explains editor Jane Lancaster (UNM). This year, two special issues were published: Mary K. Shenk (U Missouri) and I co-edited a double-issue on evolutionary and quantitative approaches to the study of kinship and Benjamin C. Campbell (U Wisconsin) guest-edited an issue on middle childhood.

HN’s special issues, in synthesizing research around areas of broad interest, often reach wide audiences. Campbell’s special issue on middle childhood was featured by noted science writer Natalie Angier in The New York Times. Lacking the “gotcha cuteness of babydom” and “secondary sexual billboards of pubescence”, middle childhood is nonetheless a critical developmental period, writes Angier. It is the time when reason, or “making sense” develops, when children begin to assert their independence and become noticed, and when body odor and sweat interact to create that musky marker of individuality that allows us to discriminate among relations, potential mates, and undesirables.

“Middle childhood is of special relevance to those interested in evolution because it represents a phase of human development critical for socialization and the development of our encultured brains,” says Campbell. During middle childhood, children only provide a fraction of their subsistence needs. How and why humans have managed to afford such a “luxurious” period of subsidized development are questions that continue to inspire theoretical and empirical research.

Campbell’s issue addresses these questions from several angles: Jennifer Thompson (UNLV) and Andrew Nelson (U Western Ontario) review fossil evidence for indications of childhood stages in our hominin ancestors. They argue that modern human childhood is distinctive in its lengthy duration and slow skeletal growth trajectory. Even Neanderthals, who show signs of a distinct middle childhood period, probably engaged in adult-like behavior earlier in order to provide the energy necessary for growing and maintaining a robust physique. David Lancy and Annette Grove (Utah State) review cross-cultural ethnographic evidence of middle childhood, showing that it is marked ceremonially on one end (the transition to adulthood) and by increasing autonomy and “getting noticed” on the other (the transition from toddlerhood).

Karen Kramer and Russell Greaves (Harvard) explore the energetics of middle childhood among the Pumé foragers of Venezuela, suggesting that fast juvenile growth can be maintained if physical activity levels are low, even in resource- poor environments. Finally, Benjamin Campbell synthesizes research relating to the role of adrenarche – the production of dehydroepiandrosterone (DHEA) that commences in middle childhood – in maintaining synaptogenesis in the brain and in the onset of biological hallmarks of development such as hair growth and the production of body odor.

Campbell’s special issue is holistic and synthetic. The hypothesized centrality of DHEA to the processes of behavioral and biological adjustment to increasing autonomy and social interaction evokes seminal work on the role of oxytocin and vasopressin in facilitating parental solicitude. These remarkably complete pictures of fundamental attributes of human life may hold the keys to understanding the labile nature of human growth and development. Parents, too, may be aided by clear delineation of a subtle life history phase during which the parent-child relationship is expected to change – a period vulnerable to the onset of ADHD, notes Campbell, when “kids are expected to be able to control themselves … and the … short attention span of ADHD interferes…”

The impact of special issues such as Campbell’s are emblematic of HN’s rising influence. “The high international rankings of HN reflect the status of our field in anthropology as well as the social sciences in general,” observes Lancaster. For members of EAS and beyond, HN remains an excellent venue for publication and may also be a go-to resource for parents bemused by the sudden appearance of pungent markers of childhood transitions.

Comments on and contributions to this column are welcome. Please send to Siobhán Mattison (sm.mattison@auckland.ac.nz).