1. 5 to 100 million species of organisms on Earth

2. All organisms on Earth are genetically related

3. “Tree of Life” Bacteria Archaea Eukaryotes All organisms are genetically related

4. P HYLOGENY History of lineages changing through time

5. NSF Assembling the Tree of Life (ATOL) Program http://atol.sdsc.edu “Increased knowledge of phylogenetic relationships will improve human health, push the frontiers of comparative developmental biology, meet threats to agriculture and forestry from invasive species and pests, and improve management of our natural resources.”

6. http://tolweb.org

7. Scientific Core Content > 6000 web pages with scientific content > 500 scientific contributors

8. Most pages are still under construction… > 6000 web pages with scientific content

9. Some content is provided by amateur contributors > 6000 web pages with scientific content > 200 treehouses (learning materials) > 20,000 images, videos, audio files

10. The structure of the Tree of Life web site illustrates phylogenetic relationships Life on Earth Rosa davurica Bembidion zephyrum Eukaryotes Insects Branch pages Leaf pages

11. http://tolweb.org

12. Homoplasy The Scourge of Phylogentic Biologists!

13. Homoplasy in Sequence Data: Long Branch Attraction A BC D D CB A Reconstructed TreeTrue Tree many informative changes few informative changes

14. How to avoid long branch attraction? Exclude long-branch taxa Exclude characters that show evidence of excessive homoplasy Use other inference methods that take branch lengths into account Split long branches by adding more taxa