Final answer:
A hypothesis about shark head shape, such as its effect on swimming efficiency, would be tested through controlled experiments measuring swimming speed and energy use, providing data to support or refute the hypothesis.
Step-by-step explanation:
The question asks how a scientist might design an experiment to test a hypothesis about the function of a shark's head shape. To address this, one must first formulate a hypothesis, such as 'The streamlined head shape of a shark reduces drag and increases swimming efficiency.' Next, controlled experiments would need to be undertaken, in which systematic observations or measurements are made. For example, scientists could compare the swimming speeds and energy expenditure of sharks with different head shapes in a controlled environment. Tags could measure the sharks' speed and sensors could analyze energy use. This would provide data to support or refute the hypothesis.
Controlled conditions are crucial to ensure that only the variable tested (head shape) influences the results. The outcomes would either generate evidence in support of the hypothesis or prove it false, and subsequently, the data collected will require thorough analysis.