Quantitative genetics: Introduction and partitioning the genetic variance
Quantitative genetics deals with the inheritance and evolution of traits that vary continuously. Such traits are typically influenced by many genes, and the same genotype typically produces somewhat different phenotypes in different environments (phenotypic plasticity). Even so, we'll develop our understanding of quantitative genetics by studying a model with only one locus and two alleles. You'll be amazed at how far we get with that simple model.
WARNING: There is an unusually large amount of math coming in the next few lectures, and it's unusually difficult to connect it to biology, because the concepts that matter - additive effect of an allele, additive genetic variance, dominance variance - are abstract mathematical ideas, not things you can observe directly. But we have to develop all of the math before you can see how to connect things that you measure to these abstract ideas and see how it really is these abstract ideas that matter.