1.What are the eras of the Phanerozoic? Name one important evolutionary event in each of those eras. •Paleozoic - The cambrian explosion •Mesozoic - Mass extinction of dinosaurs •Cenozoic - Extinction of non-avian dinosaurs and the rise of mankind 2.Define/explain the following terms: Ediacaran, Vendian, stromatolite, permineralized, Cambrian explosion, trace fossil, unconformity. •Ediacaran - Its a period that spans 94 million years from the end of the Cryogenic Period (635 mya) to the beginning of the Cambrian Period (541 mya) •Vendian - It is another word for the Ediacaran period •Stromatolites - a calcareous mound built up of layers of lime-secreting cyanobacteria and trapped sediment •Permineralized - A process of fossilization in which mineral deposits form internal casts of organisms •Cambrian Explosion - An event approximately 541 million years ago in the Cambrian period when most major animal phyla appeared in the fossil record •Trace fossil - a fossil pf a footprint, trail, burrow, or other trace of an animal rather than of the animal itself. •Unconformity - a surface of contact between two groups of uncomfortable strata 3.What are some biases of the fossil record? (i.e. what causes some organisms to be more commonly fossilized than others?) Animals with hard parts are obviously more preserved that those that have soft bodies 4. What is the difference between relative and absolute age in the geological record? Relative age is when you determine if something is younger or older based off the sequence of events and absolute age is assigning a number to the amount of time that has passed. 5. Based on the tree of skink taxa (A-G) indicate the evolutionary history of the two traits whose states are indicated and answer the following: a.Assuming parsimony, what is the ancestral state of the root for tail color? Hair color originated at the node at the end of skink A and evolved at the node of skink E and skink F to be red. b. What is the ancestral state of dorsal color pattern for the common ancestor of skink E, skink F, skink G, & skink H?The ancestor of skink E, F, G, and H was blue but evolved to be red in these generations possibly due to environmental factors. c. Identify an instance of homoplasy. An instance of homoplasy in this tree is the dorsal color pattern of skink G and skink C due to how the both evolved a same trait in different times. 6. What are some similarities and differences between parsimony and maximum likelihood methods of phylogenetic tree reconstruction? Parsimony tells us to base scientific explanation for a phylogeny on the data that provides evidence such as DNA sequence pattern. Maximum likelihood takes into account the data from the parsimony but isn't the simplest explanation but rather what is most likely to have evolved from each other. 7. What is meant by long-branch attraction? Long-Branch attraction is a systematic error whereby distantly related lineages are incorrectly inferred to be closely related. 8. Imagine a tree with three tips (species A, Species B, and Species C). What is the likelihood of observing eyes in species A and B, and no eyes in Species C? Maximum likelihood: 0.00875 9. Which is the maximum likelihood tree? Tree 1 10.a. Derive the formula for the probability of observing characters 1,1,0 (from Left to Right on the Tree Above) (1-p)*(1-p)*(1-q)*q b. Derive the formula for the probability of observing characters 1,1,1 (from Left to Right on the Tree Above)