Understanding the process of evolution by natural selection hinges on mechanistic understanding of two component processes: 1) differential survival and/or fecundity of individuals associated with the traits they possess and 2) the extent to which these traits are inherited. Inheritance is the process by which an individual receives two copies of each gene as well as the extent to which the genes affect the expression of a trait. Maternal inheritance is the special case when the mother via her own genes can directly affect the expression of a trait in her offspring. This maternal effect is independent of the genes she passes on to her offspring. This research is novel in that it will investigate the extent to which juvenile traits are not only determined by the genes an individual possesses, but also by the genes which its mother possesses. This phenotypic connection between generation is common in many organisms and can include parental provisioning and parental care. This non-standard form of inheritance can alter direction and rate of adaptive evolution. The goal of this research is to quantify the magnitude of this effect and examine how it might change the outcome of selection as it is observed in a natural population. At the most basic level this research will provide an alternative mechanism for the evolution of juvenile and maternal traits in natural plant populations. Breeders have developed a variety of breeding programs to enhance their ability to alter juvenile and maternal traits such as seed weight, emergence date and seed dispersal in plants and birth weight, gestation length and milk production in animals. These programs maximize the change in the trait of interest by selection at the individual, sibling group, or family level depending on the nature of inheritance. This research is an outgrowth of these applied problems in plant and animal breeding, but it will also make a contribution to this applied field by providing a mechanistic understanding of these non-standard forms of inheritance in plants.
