As you read each ACT Science passage, look closely for keywords that help you identify each scientist’s opinions. What does the author like? What does he dislike? What adjectives and adverbs does he use to describe the various scientific topics? He may feel positively about one thing, and negatively about another.
The evolution of the "modern" humans, Homo sapiens was a result of parallel evolution from populations of Homo erectus and an intermediary of some sort. This process occurred in Africa, Europe and Asia with some genetic intermixing among some members of these populations. There is clear anatomical evidence for this theory when comparing certain minor anatomical structures of Homo erectus populations with modern humans from these areas. These anatomical differences are so minor, this is clear evidence that modern humans must have evolved separately in Africa, Europe and Asia. This is the "Multi-Generational Hypothesis."
Which of the following best states the basis for the belief of Scientist 1?
Scientist 1 states: "These anatomical differences are so minor, this is clear evidence that modern humans must have evolved separately in Africa, Europe and Asia." Clearly, the focus of Scientist 1 is on the differences. The answer is (B).