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Bakker, F. T.

Publications and source records attributed to Bakker, F. T..

2 recordsLinked to original sources

Rampant transitions between dispersal syndromes duringangiosperm evolution

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

evolutionary biology↗

Novel insights into karyotype evolution and whole genome duplications in legumes

Legumes (family Fabaceae) are globally important crops due to their nitrogen fixing ability. Papilionoideae, the best-studied subfamily, have undergone a Whole Genome Duplication (WGD) around 59 million years ago. Recent study found varying WGD ages in subfamilies Mimosoideae and Caesalpinioideae and proposed multiple occurrences of WGD across the family based on gene duplication patterns. Despite that, the genome evolution of legume ancestor into modern legumes after the WGD is not well-understood. We aimed to study genome evolution at the subfamily level using gene-based linkage maps for Acacia auriculiformis and A. mangium (Mimosoideae) and we discovered evidence for a WGD event in Acacia. In additional to synonymous substitution rate (Ks) analysis, we used ancestral karyotype prediction to further corroborate this WGD and elucidate underlying mechanisms of karyotype evolution in Fabaceae. Using publicly available transcriptome resources from 25 species across the family Fabaceae and 2 species from order Fabales, we found that the variations in WGD ages highly correlate (R=0.8606, p-value<0.00001) with the divergence age of Vitis vinifera as an outgroup. If the variation of Ks is corrected, the age of WGDs of the family Fabaceae should be the same and therefore, parsimony would favour a single WGD near the base of Fabaceae over multiple independent WGDs across Fabaceae. In addition, we demonstrated that genome comparison of Papilionoideae with other subfamily provide important insights in understanding genome evolution in legumes.

evolutionary biology↗