The History and Consequences of Self-incompatibility in Flowering Plants (Visiting Scholar)
One of the major pursuits of evolutionary biology is the provision of a working theory that explains the generating processes behind the vastness of biodiversity. A natural starting point for such a basic--yet seemingly intractable--problem is the observation that the rules of mating between individuals determine both the amount and distribution of genetic variation within species. Breeding systems influence diversification rates, shape the evolution of other traits. Consequently, they are crucial for meaningful comparative studies of the processes that influence plant diversification. Self-incompatibility, the ability of individuals to recognize and reject their own pollen, is common in flowering plants. Inferences about its history and consequences are complicated by a trio of facts, seemingly at odds: (1) the existence of a single ancient and widespread mechanism (RNase/F-box system of nightshade, coffee, and rose families), (2) a multitude of distinct, non-homologous and independently evolved, mechanisms that enforce self-incompatibility, as well as (3) the spectacularly common loss of plant self-incompatibility within families, and indeed, the absence of self-incompatibility from many plant families. I propose to reconstruct the history and consequences of breeding system evolution in flowering plants by using a vast existing personal collection of several thousand species records to construct a formal high-quality database, recording this key trait, related traits, and primary reference information.