Molecular & Cellular. Anatomy. Biology That Makes Us Tick: Free Stanford Course by Robert Sapolsky. 7.014 Introductory Biology | CosmoLearning Biology. Exploring Life's Origins: Understanding the RNA World. The Complete Work of Charles Darwin Online. Biochemical Society. Genetics and the tree of life. We traditionally think about the tree of life in terms of Kingdoms: plants, animals, fungi, bacteria, etc. Genetics has really revolutionized the way we think about the tree of life and, because our classifications should reflect ancestry (that is, who is more closely related to whom), it has actually called into question a lot of our traditional classifications.
Most biologists split up life into three domains: Archaea, Bacteria, and Eucarya (the last of which includes animals, plants, fungi, etc.). The three domains of life. From Carl Zimmer's blog The Loom. Science writer Carl Zimmer has an interesting post on his blog about how the newest genetic data may even call this classification into question by adding a fourth domain. From his post: There’s a lot of debate about whether eukaryotes actually split off from within the archaea, or just branched off from a common ancestor. New research is looking at tons of genes from these sorts of organisms. References Wu, D., et al. (2011). Biodiversity Heritage Library. Gary Carlson - Illustration &Animation - Medical &Biological - StumbleUpon.