• Encyclopedia of Life
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.
• Integrated Taxonomic Information System
Find authoritative taxonomic information on plants, animals, fungi, and microbes of North America and the world.
• Tree of Life
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.
• Stem Cell Information: National Institute for Health
Basic information about stem cells as well as databases of stem cell research with citations and abstract of journal articles.
• Common Trees of Pennsylvania (PDF)
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.
• Crop Index
Crops are listed alphabetically by genus and common name.
• Weed Identification
Key for identifying weeds species.
• USDA PLANTS Database
Standardized information about the vascular plants, mosses, liverworts, hornworts, and lichens of the U.S. and its territories.
• CalPhotos
"A collection of 359,733 photos of plants, animals, fossils, people, and landscapes from around the world. "
