Rampant transitions between dispersal syndromes duringangiosperm evolution

Abstract

O_LIAngiosperms have evolved a diverse range of seed dispersal syndromes that have undoubtedly played a key role in their evolutionary history and rise to dominance. However, it remains largely unknown how ancestral angiosperm seeds were dispersed, when and how frequent dispersal-related characters and syndromes evolved, and whether these syndromes facilitated biome and pollination mode transitions. C_LIO_LIWe integrated a large phylogeny and several dispersal-related characters for >1200 species representing all extant angiosperm families. We used phylogenetic comparative methods to infer ancestral states of major angiosperm clades, trends in the evolution of dispersal syndromes, and evolutionary correlations between dispersal syndromes, biomes and pollination modes. C_LIO_LIWe show that angiosperms were ancestrally most likely animal-dispersed (zoochory) and had fleshy, indehiscent fruits. Over macroevolutionary time, frequent transitions between dispersal syndromes occurred, often with non-specialised (autonomous) dispersal as an intermediate state. Finally, we found that dispersal syndrome evolution affected transition rates among biomes and among pollination modes. C_LIO_LIThe number of dispersal syndrome transitions exceeded pollination mode transitions by a factor of five, emphasizing lability in dispersal syndrome evolution. The progressive evolution of diaspore complexity led to frequent and repeated evolution of dispersal syndromes, critical for the colonization of angiosperms across modern biomes. C_LI