2. What are the principal levels used in the traditional rank-based system of taxonomy? You should be able to explain why this system fits your definition of a nested hierarchy. Also, you should be able to explain why a taxonomy that is based on groupings of organisms all sharing a most recent common ancestor makes it a valid representation of nature (rather than a subjectively imposed hierarchy). 3. In the case of taxonomy, why can’t we really expect to learn with perfect certainty the actual true history of ancestry among all species that have ever lived? What are the basic tools that we use to conjecture the evolutionary history of organisms? What is the evidence used to support our models of how organisms are related to each other? 10. Jean-Baptiste Lamarck is the subject of (sometimes) benevolent ridicule in biology textbooks today (despite the fact that he practically coined the word “biology”!), and his name is typically associated with “the giraffe story.” What is “the giraffe story,” and how did his mechanism for evolutionary change fail on the basic level of how heredity works? Lamarckian evolution fails on another level in being teleological. What does this mean, and how is the true mechanism of evolutionary change inherently non- teleological? 15. In class we considered evolutionary change by natural selection to be the outcome provided three conditions are “necessary and sufficient.” The second of these (after phenotypic variation) was selection. In order to demonstrate that this condition is necessary, you should be able to argue (by logical proof) that evolution could not occur in its absence. Describe a situation in which a population has phenotypic variation but there is no selection on that phenotype. Why would such a population not be expected to evolve?