TimeTree HD

TimeTree 4 is a public knowledge-base for information on the evolutionary timescale of life. This application allows easy exploration of the thousands of divergence times among organisms in the scientific literature. A tree-based (hierarchical) system is used to identify all published molecular time estimates bearing on the divergence of two chosen organisms, such as species, compute summary statistics, and present the results. Names of two taxa to be compared are entered in the search window and the results are presented on a set of self-explanatory tabs. TimeTree 4 contains data from 2,274 studies including 50,632 species. We will be adding more data in the future as it comes in from researchers. TimeTree 4 requires iOS 8.0 or newer. The TimeTree project is jointly directed by Blair Hedges (Center for Biodiversity, Temple University) and Sudhir Kumar (Institute for Genomics and Evolutionary Medicine, Temple University). This project has been supported, in part, by grants from the National Science Foundation, National Institutes of Health, NASA Astrobiology Institute, and Science Foundation of Arizona.