Integrated Calendar

We show how the distribution of skills or phenotypes in a population acts as collective memory or "distributed information
store" serving individual so that individuals with varying innate abilities are able to
attain the mature fully skilled phenotype. We show how information moves "in" and "out" of genomes, relative to this memory system, elucidating how evolution determines where best to store information. This question applies to understanding diverse biological systems in which individuals acquire capacities from the population, including immunity, the microbiome, and social learning. Using Agent Based Modeling we investigate how properties of the
population and social aspects of the acquisition process affect the behavior of the system. We show
that the genetic properties of the population react predictably to changes in population properties that affect selection
pressures, without any group level selective processes. Specifically, parameter changes that make
acquisition slower lead to skills becoming increasingly innate while changes in parameters that improve
the results of acquisition (e.g., making acquisition reliant on abundant left-over tools) lead
to an increased reliance on acquisition, all while the average phenotype remains constant. The dynamics
we study contribute to understanding how individuals can evolve to become more or less reliant on
social learning and cultural information, how this depends on population properties (e.g., group
size), and how this manifests demographically. The more information stored externally, the stronger
the selection pressure on traits that support acquisition. Finally, we contrast our model and the Baldwin
Effect and relate out results to the study of the evolution of human social learning.