The Encyclopedia of Life (EOL) is an ambitious project to organize and make available via the Internet virtually all information about life present on Earth. At its heart lies a series of Web sites—one for each of the approximately 1.8 million known species—that provide the entry points to this vast array of knowledge. The entry-point for each site is a species page suitable for the general public, but with several linked pages aimed at more specialized users.
The Tree of Life Web Project is a collection of information about biodiversity compiled collaboratively by hundreds of expert and amateur contributors. Its goal is to contain a page with pictures, text, and other information for every species and for each group of organisms, living or extinct. Connections between Tree of Life web pages follow phylogenetic branching patterns between groups of organisms, so visitors can browse the hierarchy of life and learn about phylogeny and evolution as well as the characteristics of individual groups.
This selection of 57 native, and 5 introduced trees is organized according to leaf shape and arrangement. Each tree is identified by popular name familiar to Pennsylvanians and its complete scientific name.