What species is Lucy and Selem (use the genus and species name)? What time frame did this species exist? Where did they exist geographically? Name one trait for this species that is more apelike and one trait that is more human like. What was the environment of the Rift Valley like when Salem lived there? Review the six models in the text (Ch 10) which work to explain the evolution of bipedalism. Which model do you think is the most likely explanation? Do you think there are likely several models that might have played a role in the evolution of bipedalism? Select one or more model and briefly state why you favor that model(s). Use data from the texbook and/or video. What is competitive exclusion (see text, powerpoint for definition)? Give an example of competitive exclusion between hominin species. How does the molecular time clock give us knowledge as to when species last shared a common ancestor? When did we last share a common ancestor with chimps?