Explore the complexities of polygenic adaptation in this lecture by Nick Barton, part of the "Theoretical and Empirical Approaches to Understand Polygenic Adaptation" program. Delve into the genetic architecture of phenotypic traits, examining how multiple genetic variants influence complex characteristics like crop yield, human height, and diseases. Investigate the integration of different adaptive dynamics models, from large changes at few loci to infinitesimal changes across many. Learn about cutting-edge research bridging the gap between extreme views of adaptation and discover how these concepts relate to empirical data. Gain insights into the quantitative description of various adaptation scenarios through pedagogical lectures, research seminars, and interactive tutorial sessions. This lecture, hosted by the International Centre for Theoretical Sciences, offers a comprehensive look at the evolving understanding of biological evolution and phenotypic variation.