Download Graphic Images from the Hillis/Bull Lab Return to "Download Files" Page You are welcome to download the following graphic image of the Tree of Life for non-commercial, educational purposes: Tree of Life (~3,000 species, based on rRNA sequences) (pdf, 368 KB) (see Science, 2003, 300:1692-1697) This file can be printed as a wall poster. Tree of Life tattoo, courtesy of Clare D'Alberto, who is working on her Ph.D. in biology at the University of Melbourne. The organisms depicted in this tattoo are (starting at 4 o'clock and going around clockwise): (1) a cyanobacterium (Anabaena); (2) a radiolarian (Acantharea); (3) a dinoflagellate (Ceratium); (4) an angiosperm (Spider Orchid); (5) a couple species of fungi (Penicillium and a yeast); (6) a ctenophore (comb jelly); (7) a mollusc (nudibranch); (8) an echinoderm (brittle star); and (9) a vertebrate (Weedy Sea Dragon). Here is another great Tree of Life tattoo! Cover of Molecular Systmatics, 2nd ed Here is yet another version from Hannah Udelll at the University of Wisconson-Madisson.
What is Occams Razor? [Physics FAQ] - [Copyright] Updated 1997 by Sugihara Hiroshi. Original by Phil Gibbs 1996. Occam's (or Ockham's) razor is a principle attributed to the 14th century logician and Franciscan friar William of Ockham. Ockham was the village in the English county of Surrey where he was born. The principle states that "Entities should not be multiplied unnecessarily." "Pluralitas non est ponenda sine neccesitate" "Frustra fit per plura quod potest fieri per pauciora" "Entia non sunt multiplicanda praeter necessitatem" In fact, only the first two of these forms appear in his surviving works and the third was written by a later scholar. Many scientists have adopted or reinvented Occam's Razor, as in Leibniz's "identity of observables" and Isaac Newton stated the rule: "We are to admit no more causes of natural things than such as are both true and sufficient to explain their appearances." In physics we use the razor to shave away metaphysical concepts. References: W. W.