Since Charles Darwin's day, biologists have depicted how new
organisms evolve from old ones by adding branches to numerous trees that
represent portions of the animal, plant and microbial kingdoms.
Researchers from a dozen institutions recently completed a three-year
effort to combine tens of thousands of trees into one diagram, most
readable as a circle (below). The lines inside the circle
represent all 2.3 million species that have been named. Biologists have
genetic sequences for only about 5 percent of them, however; as more are
finished, the relationships within and across groups of species may
Anyone can propose updates to the database (OpenTreeOfLife.org). Greater detail could improve understanding of evolution and help scientists invent drugs, make crops more productive and better control infectious diseases.