Darwin's Unfinished Symphony Quotes

“When changes in one genetic trait are the source of selection for changes in a second, the rate of response in the latter depends in parts on the rate of change in the former, which, as a rule, is not fast. In comparison, if a cultural practice modifies selection acting on human genetic variation, then the greater the proportion of individuals in the population that exhibit the cultural trait, the stronger the selection on the gene. As a consequence, the rapid spread of a cultural practice often leads quickly to the maximally strong selection of the advantageous genetic variant, which rapidly increases in frequency. Cultural practices typically spread more quickly than genetic mutations, simply because cultural learning typically operates at faster rates than biological evolution. What does the speed with which a culturla trait spreads depend upon? Answer: the fidelity of cultural transmission. The very factor that is critical to the emergence of complex cumulative culture in humans is also a major determinant of evolutionary responses to that culture.”
― Kevin N Laland, Darwin's Unfinished Symphony: How Culture Made the Human Mind

“The first finding that jumped out at us was that it is possible to learn too much ! In the tournament, investing lots of time in learning was not at all effective. In fact, we found a strong negative correlation between the proportion of a strategy's moves that were INNOVATE or OBSERVE, as opposed to EXPLOIT, and how well the strategy performed. Successful strategies spent only a small fraction of their time (5-10%) learning, and the bulk of their time caching in on what they had learned, through playing EXPLOIT. Only through playing EXPLOIT can a strategy directly accrue fitness. Hencem every time a strategy chooses to learn new behavior, be it through playing INNOVATE or OBSERVE, there is a cost corresponding to the payoff that would have been received had EXPLOIT been played instead. This implied that the way to get on in life was to do a very quick bit of learning and then EXPLOIT, EXPLOIT, EXPLOIT until you die. That is a sobering lesson for someone like myself who has spent his whole life in school or university.”
― Kevin N Laland, Darwin's Unfinished Symphony: How Culture Made the Human Mind

“Also renowned is the beautiful painting ceiling of the cave at Altamira, in Northern Spain. This was the first cave art to be discovered in 1879. The art at Altamira, which has been dated to around 19,000-11,000 years ago, comprises stunning representations of bison, horses, and other large animals, with extraordinary use of colors and shading to indicate depth. The quaint story of its discovery details that the paintings, which are on a low ceiling, were initially missed by the team of archaeologists, but were spotted by one of the team's 8-year-old daughter; she was the only individual small enough to stand erect and still look up at the ceiling.”
― Kevin N Laland, Darwin's Unfinished Symphony: How Culture Made the Human Mind

“The teaching conundrum had been solved. Teaching evolves where the costs are outweighed by the inclusive fitness benefits that result from the tutor's relatives being more likely to acquire the valuable information. Teaching is not favored when the pupil can easily acquire the information on their own or through copying others. Nor is it favored when imparting traits that are difficult to learn, as teachers generally do not possess the information to pass on to their relatives. These restrictions typically lead to few circumstances under which teaching would be efficacious. Models that allow for cumulative cultural knowledge gain, however, suggest that teaching evolved in humans despite, rather than because of, our strong imitative capabilities, and primarily because cumulative culture renders otherwise difficult-to-acquire valuable information available to teach. The analyses suggest that human teaching and cumulative culture evolved together, through mutual reinforcement.”
― Kevin N Laland, Darwin's Unfinished Symphony: How Culture Made the Human Mind

“If efficient copying is adaptive, such that natural selection should favor greater and greater reliance on social as opposed to asocial learning, then the tournament also establishes that a number of characteristics strongly evocative of human culture will follow automatically. With increasing copying inevitably comes greater behavioral diversity; the retention of cultural knowledge for long periods of time; conformity; and rapid turnover in behavior such as fads, fashions, and changes in technology. Provided copying errors or innovation introduce new behavioral variants, copying can simultaneously increase the knowledge base of a population and reduce the range of exploited behavior to a core of high-performance variants. Similar reasoning accounts for the observation that copying can lead to knowledge being retained over long periods of time, yet trigger rapid turnover in behavior. Low-level performance of suboptimal behavior is sufficient to retain large amounts of cultural knowledge in social learning populations, over long periods. A high level of copying increases the retention of cultural knowledge by several orders of magnitude.”
― Kevin N Laland, Darwin's Unfinished Symphony: How Culture Made the Human Mind

“Strategies that did well in competition with other strategies were not, however, those that maximized the returns to agents. Rather, we found a strong inverse relationship between the mean fitness of individuals in populations containing only one strategy, and that strategy's performance in the tournament. This finding illustrates the parasitic effect of strategies that rely heavily on OBSERVE. Strategies using a mixture of social and asocial learning are vulnerable to being outcompeted by those using social learning alone, which may result in a population with lower average returns. These findings are evocative of an established rule in ecology; this specifies that, among competitors for a scarce resource, the dominant competitor will be the species that can persist at the lowest resource level. An equivalent rule may apply when alternative social learning strategies compete: the strategies that eventually dominates will be the one that can persist with the lowest frequency of asocial learning.”
― Kevin N Laland, Darwin's Unfinished Symphony: How Culture Made the Human Mind