According to the most recent Pteridophyte Phylogeny Group (PPG), eupolypods, or eupolypod ferns, are the most differentiated and diversified of all major lineages of ferns, accounting for more than half of extant fern...According to the most recent Pteridophyte Phylogeny Group (PPG), eupolypods, or eupolypod ferns, are the most differentiated and diversified of all major lineages of ferns, accounting for more than half of extant fern diversity. However, the evolutionary history of eupolypods remains incompletely understood, and conflicting ideas and scenarios exist in the literature about many aspects of this history. Due to a scarce fossil record, the diversification time of eupolypods mainly inferred from molecular dating approaches. Currently, there are two molecular dating results: the diversification of eupolypods occurred either in the Late Cretaceous or as early as in the Jurassic. This study uses the Bayesian tip-dating approach for the first time to infer the diversification time for eupolypods. Our analyses support the Jurassic diversification for eupolypods. The age estimations for the diversifications of the whole clade and one of its two subclades (the eupolypods II) are both in the Jurassic, which adds to the growing body of data on a much earlier diversification of Polypodiales in the Mesozoic than previously suspected.展开更多
Inferring divergence times between lineages is crucial for understanding biological evolutionary processes. The extraordinary species diversity of Eupolypods within the fern lineage has been interpreted as an ecologic...Inferring divergence times between lineages is crucial for understanding biological evolutionary processes. The extraordinary species diversity of Eupolypods within the fern lineage has been interpreted as an ecological opportunistic response to the emergence of more complex, angiosperm-dominated ecosystems. This co-adaptation between Eupolypods and angiosperms has prompted ongoing investigations into the phylogenetic and diversification timelines of Eupolypods. In this study, we incorporate newly discovered fossils of Dryopteridaceae, including two species from both the stem and crown groups, to reanalyze the phylogenetic and diversification times of Eupolypods using total-evidence dating (TED or tip-dating) methods. Our analyses confirm that Eupolypods first diversified during the Jurassic and suggest that both subclades, Polypodiineae and Aspleniineae, underwent their earliest diversification during this period, challenging recent claims that Polypodiineae diversified no earlier than the Cretaceous. These results support a “long fuse” model, indicating that the initial emergence of Polypodiales preceded their diversification and extensive fossil record. Furthermore, our findings clarify the systematic position of Hypodematiaceae, indicating that it, along with Didymochlaenaceae, represents the basal lineages of Polypodiineae. This study highlights the critical role of fossil abundance and taxonomic composition in molecular dating analyses.展开更多
文摘According to the most recent Pteridophyte Phylogeny Group (PPG), eupolypods, or eupolypod ferns, are the most differentiated and diversified of all major lineages of ferns, accounting for more than half of extant fern diversity. However, the evolutionary history of eupolypods remains incompletely understood, and conflicting ideas and scenarios exist in the literature about many aspects of this history. Due to a scarce fossil record, the diversification time of eupolypods mainly inferred from molecular dating approaches. Currently, there are two molecular dating results: the diversification of eupolypods occurred either in the Late Cretaceous or as early as in the Jurassic. This study uses the Bayesian tip-dating approach for the first time to infer the diversification time for eupolypods. Our analyses support the Jurassic diversification for eupolypods. The age estimations for the diversifications of the whole clade and one of its two subclades (the eupolypods II) are both in the Jurassic, which adds to the growing body of data on a much earlier diversification of Polypodiales in the Mesozoic than previously suspected.
文摘Inferring divergence times between lineages is crucial for understanding biological evolutionary processes. The extraordinary species diversity of Eupolypods within the fern lineage has been interpreted as an ecological opportunistic response to the emergence of more complex, angiosperm-dominated ecosystems. This co-adaptation between Eupolypods and angiosperms has prompted ongoing investigations into the phylogenetic and diversification timelines of Eupolypods. In this study, we incorporate newly discovered fossils of Dryopteridaceae, including two species from both the stem and crown groups, to reanalyze the phylogenetic and diversification times of Eupolypods using total-evidence dating (TED or tip-dating) methods. Our analyses confirm that Eupolypods first diversified during the Jurassic and suggest that both subclades, Polypodiineae and Aspleniineae, underwent their earliest diversification during this period, challenging recent claims that Polypodiineae diversified no earlier than the Cretaceous. These results support a “long fuse” model, indicating that the initial emergence of Polypodiales preceded their diversification and extensive fossil record. Furthermore, our findings clarify the systematic position of Hypodematiaceae, indicating that it, along with Didymochlaenaceae, represents the basal lineages of Polypodiineae. This study highlights the critical role of fossil abundance and taxonomic composition in molecular dating analyses.
