TimeTree is a free public database developed by S. Blair Hedges and Sudhir Kumar, now at

Temple University Temple University (Temple or TU) is a public state-related research university in Philadelphia, Pennsylvania. It was founded in 1884 by the Baptist minister Russell Conwell and his congregation Grace Baptist Church of Philadelphia then calle ...

, for presenting times of divergence in the

tree of life The tree of life is a fundamental archetype in many of the world's mythological, religious, and philosophical traditions. It is closely related to the concept of the sacred tree.Giovino, Mariana (2007). ''The Assyrian Sacred Tree: A Hist ...

. The basic concept has been to produce and present a community consensus of the timetree of life from published studies, now numbering 3,998, and allow easy access to that information, on the web or mobile device. The database permits searching for average node times between two

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriat ...

or higher taxa and building of a timetree of life for a higher taxa. TimeTree has been used in public education to conceptualize the evolution of life, such as in high school settings. The original development of TimeTree dates to the late 1990s, with initial support fro
NASA Astrobiology Institute
Since then it has been supported by additional grants fro
NASA
and b
NSF
an
NIH

Features

TimeTree users can search for the names of two species, such as cat and dog, to obtain the mean and median time estimates for their divergence, in millions of years. The results also show all individual time estimates, from each study, next to a geologic timescale, indicating geologic periods. Separately, a table lists the time estimates, downloadable as a spreadsheet, from each study along with references and links to the abstracts of the original articles. The database also allows search of timetree articles by author name. The entire book ''Timetree of Life'' is also presented on the site.

References

{{reflist

External links

TimeTree Homepage

NASA Astrobiology Institute

NASA

NSF

NIH
Bioinformatics software