This proposal has two overarching inter-connected goals. First, we aim to understand the basic mechanisms that support meiotic genome haploidization in eukaryotes. We will investigate how cells implement alignment of parental homologous chromosomes, chromosome breakage, crossover recombination and kinetochore function in preparation for meiosis I. Second, we aim to delineate the mechanisms by which meiosis is 'repurposed' for asexual reproduction in parthenogenetic organisms.