Questions: Biocultural Human Ecology and Adaptation

Question 1

Lactase persistence — the ability to digest milk into adulthood — evolved to high frequency in populations with long traditions of cattle pastoralism. What does this example best illustrate about biocultural evolution?

• A. Biological traits are determined by environment, not by culture
• B. Cultural practices can create selective environments that drive genetic evolution in the same population
• C. Cultural adaptation is always faster than biological adaptation, so culture caused the genetic change by outpacing it
• D. Humans adapted biologically to survive without culture once dairy farming ended

Answer: (B)

Lactase persistence is the canonical example of biocultural feedback: the cultural practice of keeping cattle and drinking milk created a new selective environment in which the lactase persistence allele was advantageous. Culture (pastoralism) changed what genes were favored — this is culture shaping biological evolution. Option C misunderstands the mechanism: the point isn't just about speed but about direction — culture actively creates the selective conditions that guide genetic change.

Question 2

A biocultural anthropologist studying high rates of Type 2 diabetes in a particular immigrant community considers genetic predisposition, developmental nutrition in utero, traditional dietary culture, and socioeconomic barriers to healthy food. Which frame does this analysis represent?

• A. Environmental determinism — the environment forces health outcomes
• B. Pure biological reductionism — disease has a genetic cause and everything else is secondary
• C. A triple-adaptation analysis integrating genetic, developmental, and cultural-ecological factors simultaneously
• D. Medical anthropology rejecting genetic explanations in favor of cultural ones

Answer: (C)

This analysis represents the biocultural approach: no single explanation (genes, culture, environment) suffices alone. The 'triple adaptation system' integrates genetic evolution, developmental plasticity (in-utero nutrition), and cultural-ecological factors (diet, access). Option D mischaracterizes the approach — biocultural anthropology doesn't reject genetic explanations but rather insists neither genes nor culture alone is sufficient.

Question 3

Biological adaptation is typically slow (operating over many generations), while cultural adaptation is rapid — so in the short term, mainly cultural adaptation matters.

• T. True
• F. False

Answer: False

This common assumption is false. Epigenetic changes can alter gene expression within a single generation in response to environmental conditions. Developmental plasticity — the body's adjustment during growth in response to nutrition, altitude, or disease load — can produce significant biological changes within a lifetime. Meanwhile, cultural change can sometimes be very slow (traditions, foodways, and ritual practices can persist for centuries). The clean separation of 'fast culture / slow biology' oversimplifies both.

Question 4

A population's cultural practices can create selective pressures that drive genetic evolution within that same population over generations.

• T. True
• F. False

Answer: True

This is the core mechanism of biocultural feedback, sometimes called 'gene-culture coevolution.' When a cultural practice changes the selective environment (as cattle pastoralism did for lactase persistence, or mosquito-net use modified the selective landscape for malaria resistance), biology responds over generations. Culture and genes do not evolve independently — each shapes the selective environment the other faces.

Question 5

Why do biocultural anthropologists argue that the nature/culture divide is false? What does treating them as separate domains miss?

Model answer: The nature/culture divide is false because biology and culture continuously interact and reshape each other rather than operating independently. Genes are not fate — cultural practices modify which genes are expressed and which are selected for. Culture is not free-floating — it is constrained by biological and ecological realities. What we eat, how we organize labor, how we respond to illness are simultaneously biological acts and cultural ones. Treating them separately misses the feedback loops where each domain creates the conditions that drive change in the other.

The practical consequence is that neither pure biological nor pure cultural explanations are adequate for understanding human health, behavior, or history. Medical anthropology, evolutionary medicine, and public health all benefit from holding both levels simultaneously — explaining, for instance, why the same pathogen causes very different disease patterns across populations with different biological histories and cultural arrangements.