Wild-type and peloric flowers of Antirrhinum majus. Darwin noted the near-complete dominance of the wild type and the segregation of the recessive allele in the F2. This is a floral trait determined by a single recessive allele and could have given Darwin the Mendelian ratios if he had pursued his breeding experiments. Photograph kindly provided by and copyright Enrico Coen. Reproduced with permission.
Howard Journal of Biology 2009 8:15 doi:10.1186/jbiol123