"Parental effects – the expression of offspring traits depending upon the influence of parental phenotype -have become a major focus of interest in behavioural and evolutionary biology. They represent potentially very important epigenetic component of offspring phenotype that can advance, slow or even reverse phenotypic changes in response to selection. The simultaneous selection on parental and offspring traits is thought to result in a co-adaptation of parental and offspring traits which may result in negative or positive genetic correlations depending upon the selection pressures. This has mostly been studied in the context of post-hatching parent-offspring co-adaptation, with the focus on the co-adaptation in parental supply and offspring demand mechanisms. More recently, pre-hatching influences on offspring development and their influence on post-hatching parent-offspring interactions have become a major research focus due to the discovery of maternal hormones. However the genetic basis of pre-hatching parent-offspring co-adaptation has not been studied, nor how it relates and affects post-hatching parent-offspring interactions. I intend to study the genetic basis of pre-hatching parent-offspring co-adaptation, and its influence on post-hatching parent-offspring interactions. I will use specific breeding designs and genetic markers to separate and direct genetic effects from genetic and non-genetic parental effects. I will use theoretical modelling to understand how different types and mechanisms of parental effects evolve or influence evolution when selection on parents and offspring differs, focusing on the interaction of prenatal and postnatal maternal effects. Finally, I will experimentally test the functional consequences for parents and offspring when pre-hatching parental investment and offspring development is matched or mismatched and its interaction with post-hatching interactions."