Topic of Book
The authors continue their research on the relationship between human biology, culture and learning. “Not By Genes Alone” is much accessible to a general audience, but this summary is worth reading.
- Culture is critical to understanding human behavior and evolution.
- Culture is not separate from biology; culture is part of human biology.
Important Quotes from Book
“Over the last 30 years, we have worked to develop a theory and supporting evidence to account for the evolution of the human capacity for culture and how this capacity leads to distinctive evolutionary patterns…”
“Our research can be summarized by five propositions:
- Culture is information that people acquire from others by teaching, imitation, and other forms of social learning. On a scale unknown in any other species, people acquire skills, beliefs, and values from the people around them, and these strongly affect behavior…
- Culture change should be modeled as a Darwinian evolutionary process…
- Culture is part of human biology. The capacities that allow us to acquire culture are evolved components of human psychology, and the contents of cultures are deeply intertwined with many aspects or our biology. What we learn, what we feel, how we think, and how we remember are all shaped by the architecture of human minds and bodies shaped over the millennia by the ongoing action of organic evolution. As a result, much cultural variation can be understood in terms of human evolutionary history.
- Culture makes human evolution very different from the evolution of other organisms. Humans, unlike any other living creature, have cumulative cultural adaptation. Humans learn things from others, improve those things, transmit them to the next generation, where they are improved again, and so on, leading the rapid cultural evolution of superbly designed adaptations to particular environments… This opens the door to the spread of “maladaptive” ideas, ideas that would never evolve in a nonculture organism.
- Genes and culture coevolve. Because culture creates durable changes in human behavior, human genes evolve in a culturally constructed environment. This environment, in turn, generates selection on genes… Much of what human organic evolution has been about is the coevolution of capacities for culture and cultural traditions.”
Think of culture as a pool of information, mainly stored in the brains of a population of people. This information gets transmitted from one brain to another by various social learning processes. We define culture as follows: Culture is information capable of affecting individuals’ behavior that they acquire from other members of their species by teaching, imitation, and other forms of social transmission. By “information”, we mean any individual attribute that is acquired or modified by social learning and affects behavior.
“human-style social learning creates a novel evolutionary trade-off. Social learning allows human populations to accumulate reservoirs of adaptive information over many generations, leading to the cumulative cultural evolution of highly adaptive behaviors and technology. Because this process is much faster than genetic evolution, it allows populations to evolve (culturally) adaptations to local environments… However, the same psychological mechanisms that create this benefit necessarily come with a built-in cost. To get the benefits of social learning, human have to be credulous, for the most part accepting the ways that they observe in their society as sensible and proper, but such credulity opens human minds to the spread of maladaptive beliefs. The problem is one of information costs. The advantage of culture is that individuals don’t have to invent everything for themselves.”
“The human species is a spectacular evolutionary anomaly, and we ought to expect that the evolutionary system behind it is anomalous as well.”