An early burst of skeletal evolution at the origin of dinosaurs

Over 230 million years of Earth history, dinosaurs became a major terrestrial animal clade and produced one of the most species-rich living tetrapod lineages, birds. Yet, largely because of uncertainty surrounding the phylogeny and geographic origins of dinosaurs, the tempo and mode of their emergence and initial radiation remain poorly constrained. Here, we reconstruct the initial diversification of dinosaurs through Bayesian tip-dating analyses. Using seven morphological datasets to account for uncertainty, we suggest that dinosaurs emerged between 250 and 240 Ma, 10 million years before the earliest unambiguous dinosaur fossils. The emergence of the dinosaurs was followed by the rapid appearances and diversification of all major lineages, coinciding with a burst of morphological evolution that peaked in the early Late Triassic. The patterns we infer are consistent with the expectations under a scenario of evolutionary radiation, in which ecologically disparate lineages rapidly divers..., , # An early burst of skeletal evolution at the origin of dinosaurs

Dataset DOI: [10.5061/dryad.w9ghx3g33](10.5061/dryad.w9ghx3g33)

## Description of the data and file structure

README

These compressed files contain all information necessary to replicate our phylogenetic analyses. Each dataset analyzed has a folder named after it, which contains subfolders for each of the ten chains that we ran, named \"Chain_1\" through \"Chain_10\".

Each chain folder contains the following files:

\*.out: A text file showing the BEAST 2 output. This displays the random starting seed for this chain, enabling exact replication, as well as all MCMC outputs.

\*.err: A text file showing any messages (including error messages) displayed during the run

NameChain#_SLURM.sh: The SLURM file used to run the analysis in Princeton's high-performance computing cluster. The exact BEAST 2 command can be seen here.

NameChain#.log: The log file for this chain.

NameChain#.trees: The tree file for this chain.

NameCha..., ,