Detailed breakdown of data availability.

The number of studies with available phylogenetic data—as tree files (green), alignments files (orange) or both (blue), procured either from online archives or by direct request—organized by year of publication (barplot). Phylogenetic data of some kind (tree and/or alignment files) were available from an online archive for approximately of the studies, and additional data were successfully solicited by direct request for of the studies. Complete datasets were unavailable for of published studies, and data of any kind were unavailable for of studies (gray). The ‘policy’ arrow indicates the onset of several community initiatives to improve the sharing and preservation of evolutionary (including phylogenetic) data, which coincides with a marked increase in the deposition of phylogenetic data to online archives. For each pair of barplots, the left/right bars correspond to archived/solicited data, respectively. Grayscale image available at http://dx.doi.org/10.6084/m9.figshare.1148872.