Kevin Laland’s Darwin’s Unfinished Symphony is sure to make my top five and the early favorite to make number one. It got a mention from Tyler Cowen and a brief review from Robin Hanson. I would be curious to know what Jason Collins thinks of it. Laland is a person I would very much like to spend a few hours with batting ideas around.

Laland’s field is evolutionary neuroscience, or so I would guess. The book is focused on the co-evolution of brain capabilities and culture in humans. A central question is how culture came to be so advanced in humans relative to animals. To address that, one must try to understand how culture is developed, transmitted, and retained.

On page 7, Laland offers his definition of culture as

the extensive accumulation of shared, learned knowledge, and iterative improvements in technology over time.

Recall that my working definition of culture is “socially communicated thought patterns and behavioral tendencies.”

Late in the book, Laland uses dance as an example of culture.

The social structure of many communities. . .gain much of their cohesion from the group activity of dancing. Historically, dance has been a strong, binding influence on community life, a means of expressing social identity of the group, and participation allows individuals to demonstrate a belonging. . .there are as many types of dances as there are communities with distinct identities.

Of course, I like this choice of examples. I think that dance illustrates what I see as a trend in recent decades toward narrower, deeper, older.

One of the central scientific studies in the book is the social learning strategies tournament. In the tournament, each player faces an environment that changes gradually over a sequence of turns. To cope with this environment, at each turn the player can choose one of three moves. Quoting from the article,

INNOVATE, OBSERVE and EXPLOIT. INNOVATE represented asocial learning, that is individual learning stemming solely through direct interaction with the environment, for example, through trial-and-error. An INNOVATE move always returned accurate information about the payoff of a randomly selected behavior previously unknown to the agent. OBSERVE represented any form of social learning or copying through which an agent could acquire a behavior performed by another individual, whether by observation of or interaction with that individual An OBSERVE move returned noisy information about the behavior and payoff currently being demonstrated in the population by one or more other agents playing EXPLOIT. . . Finally, EXPLOIT represented the performance of a behavior from the agent’s repertoire

As long as the environment stays reasonably stable, you profit most from EXPLOIT. But as the environment changes, you can obtain higher payoffs by learning. In the simulation exercise conducted in the study, the social learning strategy OBSERVE worked much better than the asocial learning strategy INNOVATE. It seems to me that people who play OBSERVE get to free ride on others who are playing EXPLOIT and to free ride especially profitably on others who play INNOVATE.

Think of a factory worker in Ohio in 1999. If you just go to work every day expecting your job to last forever, you are playing EXPLOIT. If you decide to study the career choices and location decisions of people you think are similar to you, you are playing OBSERVE. If you decide to pick a new career and/or location based mostly on your own instincts, you are playing INNOVATE. The signals you get from playing OBSERVE are noisy. You could end up copying someone who develops computer network management skills and moves somewhere to run a data center. Or you could end up copying someone who goes on disability and gets addicted to opioids.

I think that this very simple model helps one to think about the PSST story for a recession. During boom times, people find patterns of specialization and trade that are rewarding, and they EXPLOIT them. But people may over-estimate the stability of that environment. They think that house prices will never go down. They think that manufacturing jobs are going to last. Then, as the environment changes and as those changes become manifest, a lot of people’s EXPLOIT strategies start to work out badly. They have to go into learning mode. They are used to having OBSERVE work out best, and that may still be the case from the perspective of the individual, but it means that the process of establishing new patterns of specialization and trade will take a long time. To speed up that process, from a social perspective we may need more people to play INNOVATE.

Anyway, there is a lot to the book, and I plan to write a fuller review.