A fern from the French Pyrenees—×Cystocarpium roskamianum—is a recently formed intergeneric hybrid between parental lineages that diverged from each other approximately 60 million years ago (mya; 95% highest posterior density: 40.2–76.2 mya). This is an extraordinarily deep hybridization event, roughly akin to an elephant hybridizing with a manatee or a human with a lemur. In the context of other reported deep hybrids, this finding suggests that populations of ferns, and other plants with abiotically mediated fertilization, may evolve reproductive incompatibilities more slowly, perhaps because they lack many of the premating isolation mechanisms that characterize most other groups of organisms. This conclusion implies that major features of Earth’s biodiversity—such as the relatively small number of species of ferns compared to those of angiosperms—may be, in part, an indirect by-product of this slower “speciation clock” rather than a direct consequence of adaptive innovations by the more diverse lineages.
DatingAnalysis1_combnd_burninout
DatingAnalysis1_combnd_burninout
Posterior sample of divergence times, etc., from the four DatingAnalysis1 (eupolypods II) runs, combined, with the burnin removed.
DatingAnalysis1_run1of4log
Posterior sample of divergence time, etc., from one of the four DatingAnalysis1 (eupolypods II) runs.
DatingAnalysis1_run1of4.log
DatingAnalysis1_run1of4trees
Posterior sample of time trees from one of the four DatingAnalysis1 (eupolypods II) runs.
DatingAnalysis1_run1of4.trees
DatingAnalysis1_run1of4xml
Beast XML (alignment, settings, etc.) from one of the four DatingAnalysis1 (eupolypods II) runs.
DatingAnalysis1_run1of4.xml
DatingAnalysis2_combd_burninouttree
Posterior sample of time trees from the four DatingAnalysis2 (Cystopteridaceae) runs, combined, with the burnin removed.
DatingAnalysis2_combd_burninout.tre
DatingAnalysis2_combnd_burninoutlog
Posterior sample of divergence times, etc., from the four DatingAnalysis2 (Cystopteridaceae) runs, combined, with the burnin removed.
DatingAnalysis2_combnd_burninout.log
DatingAnalysis2_run1of4log
Posterior sample of divergence times, etc., from one of the four DatingAnalysis2 (Cystopteridaceae) runs.
DatingAnalysis2_run1of4.log
DatingAnalysis2_run1of4trees
Posterior sample of time trees from one of the four DatingAnalysis2 (Cystopteridaceae) runs.
DatingAnalysis2_run1of4.trees
DatingAnalysis2_run1of4xml
Beast XML (alignment, settings, etc.) from one of the four DatingAnalysis2 (Cystopteridaceae) runs.
DatingAnalysis2_run1of4.xml
Rscript_xCysto_posterior_distributions_fitting_etc
An R script for extracting the posterior node age distributions from the Beast outputs, and then fit parametric distributions to them. And to compare distributions (plot them).
xCysto_posterior_distributions_fitting_etc.R
xCysto_alleles_garli configuration file
The Garli configuration file for the Cystopteridaceae alleles dataset analysis.
xCysto_alleles_garli.conf