Conditions that favour cumulative cultural evolution

Area of Science:

• Evolutionary biology
• Anthropology
• Cognitive science

Background:

• Human cumulative culture is a major evolutionary transition, yet its rarity is puzzling despite fitness advantages.
• Previous models (Boyd & Richerson, 1996) explored conditions favoring social learning but had limitations.

Purpose of the Study:

• To extend the discrete-cultural-trait model to investigate barriers to cumulative culture.
• To analyze the impact of strong selection, various transmission biases, environmental variation, and finite populations on cultural evolution.

Main Methods:

• Extended Boyd & Richerson's (1996) discrete-cultural-trait model.
• Incorporated strong selection, conformist/anti-conformist/unbiased transmission, environmental variation, finite populations, and multiple skill levels.

Main Results:

• The advantage of social learning over individual learning under specific conditions depends on the number of observed individuals (n).
• Finite populations and frequency-dependent transmission can allow for larger n, influencing the conditions under which social learning is favored.
• The increase in mean skill level is reduced when cumulative culture is initially absent, population size is finite, or transmission is frequency-dependent.

Conclusions:

• Multiple factors, including finite population size and frequency-dependent transmission, act as barriers to cultural accumulation.
• These barriers may explain why high degrees of cumulative culture are rare in nature, despite potential benefits.