Now that you have considered the different habitats in which the white clover is found and the factors affecting fitness in clover, you will develop hypotheses to explain the observed distribution of plain and striped clover. A hypothesis is a tentative answer to a well-framed question. This means that one has developed an explanation of an event based on preliminary data, observations, and perhaps the work of other scientists. Scientists use observations and data to develop and justify their hypotheses. A hypothesis is presented as a statement, not a question, and must be both testable (there must be some way to test if it is valid) and falsifiable (it must be possible to show that an incorrect hypothesis is false).
Based on the data presented above and the differences in habitat between Minnesota and North Carolina, propose a hypothesis to explain each of the following: a) the higher frequency of plain clover in Minnesota, and b) the higher frequency of cyanide producing/striped clover in North Carolina. Justify the reasoning leading to each of your hypotheses. Be specific in terms of which variables (conditions) affect the frequency of each type of clover in each habitat. Remember to write your hypotheses as statements, not as questions.
Are your hypotheses the same for the different habitats? Explain why individuals or populations from the same species may show different traits in different habitats. Use the term “selection pressure” in your explanation. Selection pressure refers to the influence a particular factor has on the ability of an organism to survive and reproduce.
Once a scientist has formed a hypothesis, the next step is to test it with observations or experiments. Experiments should test only one variable at a time, and keep as many other factors as possible constant (which doesn’t mean “unchanging,” but only that they are the same for all experimental groups). Design experiments to test at least one hypothesis for each habitat.
For each of the experiments you proposed in Exercise 6, describe data that would support your hypothesis and data that would falsify your hypothesis.
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