Mind the gap(s)... in theory, method and data: Re-examining Kanazawa (2006).

Area of Science:

• Evolutionary psychology
• Human longevity
• Societal intelligence

Background:

• Kanazawa's (2006) theory posits higher general intelligence drives longevity in affluent societies.
• This theory suggests intelligence, not wealth or egalitarianism, determines health and lifespan.
• The theory claims this correlation doesn't apply to sub-Saharan Africa.

Discussion:

• Critiques adaptationist views, arguing natural selection addresses specific, not general, problems.
• Challenges the assumption that sub-Saharan Africa represents the evolutionary past.
• Questions the plausibility of contemporary health hazards being evolutionarily novel.

Key Insights:

• Kanazawa's cross-national analysis shows a correlation between national IQ and mortality data.
• The study argues Kanazawa infers causation from correlation, ignoring alternative explanations.
• Methodological flaws in IQ data (sample size, sampling, consistency) undermine the findings.

Outlook:

• Re-evaluating the relationship between intelligence, societal factors, and health outcomes is necessary.
• Further research should employ robust methodologies and consider diverse populations.
• Investigating the complex interplay of genetics, environment, and socioeconomic factors on longevity is crucial.