Possible adaptive and non-adaptive radiation in three plant genera in the Japanese archipelago

The adaptive radiation of flowering plants as manifested by the floral diversity has long been considered associated with the diversity of plant-pollinator interactions, because changes in plant-pollinator interactions are hypothesized as one of the major mechanisms driving plant ecological speciation. To understand the relative contributions of various mechanisms for plant radiation, including pollinator changes, it is useful to study a plant group for which comparative study of the species life history across the whole lineage is feasible. To this end, we will focus on the plant lineages that have presumably radiated in the Japanese archipelago, namely, the genera Asimitellaria, Asarum, and Arisaema. By comparing these three genera, we will comment on the possible modes of adaptive radiation and diversification among the endemic flora of Japan.