National Geographic News

National Geographic News


In this exercise, you will learn about scientific debates, alternative hypotheses, and how there can be more than one explanation for the same set of scientific evidence by reading the National Geographic News online article, “Hermaphrodite Frogs Caused by Popular Weed Killer?”

After reading the article, answer these questions:

Using your own words, state Tyrone Hayes’ explanation, in the form of a scientific hypothesis, for the cause of abnormal sexual development in male frogs.



Provide an example of evidence cited by Tyrone Hayes to explain his theory for abnormal sexual development observed in male frogs. 



Provide an example of scientific evidence cited by Ernest Smith and John Giesy explaining why they disagree with Tyrone Hayes’ theory.



Do you think that Dr. Hayes’ suspicion that increasing levels of the enzyme aromatase (which converts testosterone to estrogen) in male frogs is an explanation or evidence for their feminization?



What are some possible explanations for the difference in opinion between Hayes and Smith and Giesy?



Based upon what you read, use your own words to define peer review.



Why is peer review important in science?



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