Data from: Phylogenomic insights into the cambrian explosion, the colonization of land and the evolution of flight in arthropoda

The timing of the origin of arthropods in relation to the Cambrian explosion is still controversial, as are the timing of other arthropod macroevolutionary events such as the colonization of land and the evolution of flight. Here we assess the power of a phylogenomic approach to shed light on these major events in the evolutionary history of life on earth. Analyzing a large phylogenomic dataset (122 taxa, 62 genes) with a Bayesian-relaxed molecular clock, we simultaneously reconstructed the phylogenetic relationships and the absolute times of divergences among the arthropods. Simulations were used to test whether our analysis could distinguish between alternative Cambrian explosion scenarios with increasing levels of autocorrelated rate variation. Our analyses support previous phylogenomic hypotheses and simulations indicate a Precambrian origin of the arthropods. Our results provide insights into the 3 independent colonizations of land by arthropods and suggest that evolution of insect wings happened much earlier than the fossil record indicates, with flight evolving during a period of increasing oxygen levels and impressively large forests. These and other findings provide a foundation for macroevolutionary and comparative genomic study of Arthropoda.Insect8_no3rdTree FileTable S1 Sampled TaxaList of Sampled Taxa, their data and sourcesTable S2 Pairwise genomic agesTable S3 simulation resultsFigS1 v2Figure S1. Schematic of the 'short fuse' Cambrian explosion simulation analyses. Using all branch lengths 520 Ma were modified to conform to a 'short fuse' Cambrian explosion event at 540 to 530 Ma (panel B). Branch lengths of this resulting tree were then modified at different levels of autocorrelated rate variation (panel C). For no rate variation among branches, the coefficient of variation (CoV) among branch rates is 0 (and there is only 1 tree). For each of the higher levels of rate variation, 10 different realizations of autocorrelated branch length manipulation were generated (with some examples shown in panel C). Each of these trees was then used as a template for generating simulated DNA datasets and then analyzed using BEAST and the same parameters as our observed data. Histograms of the distribution of posterior estimates for the age of the Arthropoda are show, for the three different levels of CoV shown in panel C, with posterior values pooled among replicates