I don't think knowing Mendel's work would have helped Darwin much. Just look at the mess it caused at the turn of the century. What genetics did for Darwin wasn't apparent until the 1920's and 30's, when Fisher, Haldane and Wright showed how selection acted on genes in populations. By showing that even slight selective advantages could produce significant changes in the genetic structure of populations over time, Darwin's idea of gradual change was saved from being thrown out altogether.
quote:Perhaps not Mendel's work specifically, but if he had known of genetics and DNA as the mode of transmission of variation, it would have filled in some gaps. However, it would not have changed his theory.