Homo sapiens

Alexandrine parakeet

Psittacula eupatria


Million Years Ago (TTOL)
Mean: 311.90 Mya
Median: 318.45 Mya



Homo sapiens

Alexandrine parakeet

Psittacula eupatria
311.9 Million Years Ago (TTOL)

318.4 Mya (median, 30 studies)

Click on timescale or black dots for more info.

Molecular Time Estimates

*Note: If you would like to suggest your publication for inclusion, and it is not yet in TimeTree (see list of studies), you can send us the reference information for the publication using the contact page.

Time Reference Year
319.0 Laurin et al. 2018
312.2 Delsuc et al. 2018
319.3 Feng et al. 2017
177.3 O'Connor et al. 2015
324.7 dos Reis et al. 2015
315.8 Wang et al. 2013
271.0 Jones et al. 2013
329.1 Crottini et al. 2012
174.1 Liu et al. 2012
318.9 Shen et al. 2012
334.7 Parfrey et al. 2011
317.4 Shen et al. 2011
315.9 Meredith et al. 2011
328.4 Okajima et al. 2010
322.4 San Mauro et al. 2010
314.0 Inoue et al. 2010
310.0 Subramanian et al. 2010
308.5 Berbee et al. 2010
320.7 Roelants et al. 2010
317.9 Pyron et al. 2010
316.0 Phillips et al. 2009
320.3 Alfaro et al. 2009
324.5 Hedges et al. 2009
321.4 Okajima et al. 2009
318.0 Amer et al. 2008
312.0 Igawa et al. 2008
315.4 Kumazawa et al. 2007
328.0 Vieites et al. 2007
323.6 Pereira et al. 2006
326.0 Blair et al. 2005

CAUTION: We recommend that the users carefully examine individual study results provided before using summary information.

How It Works

Two species or higher taxa are queried (e.g., cat and dog).

TimeTree looks for these species in the TTOL to find their most recent common ancestor and produces the time estimate available. All studies with published times of divergence for that evolutionary split are shown in a Table format. When one or both of the species are not present in TTOL, the NCBI taxonomy is scanned to find the closest relatives of the species or higher taxa requested by the user. Then, those taxa are used as proxies and the most recent common ancestor identified to generate the final time estimates.



The TimeTree of Life from an assembly of all individual timetrees from the Time Tree of Life book. Order an offset print or download the file to print your own.


On our Results page, you can download all individual time estimates and study data associated with the query. The iPhone and iPad apps, and all chapters of the Timetree of Life book, can be downloaded by using their respective links. In addition, we will soon make available a facility to download timetrees consisting of multiple species, where users will also be able to input their own species trees. These facilities will be available for a large number of species (>50,000 species) as soon as we complete the processing and synthesis of results from over 2000 studies into this resource. In the meantime, we provide the >50,000-species timetree of life as a download here.

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