Publication and editorial responsibility
Ptree — Interactive Tree of Life Explorer is part of the Ptable network of independent science references. Published at ptree.org, it is a secondary source that assembles and interprets biological evidence. Michael Dayah is responsible for its conception, design, software, data integration and editorial content.
Ptable has been accessible from the same URL for 29 years and maintained independently since 1997. Ptree extends that work in interactive scientific reference to the tree of life.
Publication, permissions and correction inquiries: contact Michael Dayah. Media information and downloadable assets are available on the press page.
Copyright and trademarks
Original Ptree code, interface and editorial content © 2026 Michael Dayah. Ptree™ identifies this reference and its related materials. Ptable® is a registered trademark of Michael Dayah.
Educational screenshots and recordings are welcome with credit. See Citing Ptree for educational use, publication permissions, embedding and redistribution.
Scientific data, photographs, illustrations, maps and encyclopedia content retain their respective source licenses. The copyright notice for Ptree's original work does not replace those licenses. Individual silhouette credits are listed in the illustration register.
Data attribution and transformations
Ptree uses material published by scientific institutions, research projects and individual contributors under the terms documented in Sources & licenses. For material used under Creative Commons Attribution, Ptree credits the provider, links the applicable license and identifies its transformations: matching records across classifications, normalizing units and vocabulary, and aggregating evidence into group summaries. Source records and citations remain available behind the displayed values.
CC BY 4.0 permits sharing and adaptation, including commercial use, subject to its attribution and other terms. Materials under ShareAlike, NonCommercial or other licenses retain those conditions. Attribution identifies the origin of the material; it does not imply a provider's endorsement of Ptree.
The methodology describes Ptree's interpretation and evidence handling. The citation guide explains how to acknowledge the explorer and its contributing sources.
Privacy
The privacy statement describes access logs, aggregate analytics, error reports and browser-stored preferences.