Question

masteringbio JFor each of the studies described below, indicate if it is hypothesis driven and whether the scientist is employing observational or manipulative methods. Match the words in the left column to the appropriate blanks in the sentences on the right. Words can be used once, more than once, or not at all.

Answer 1

Incomplete question. The remaining part of the question read;

Words in the left column:

• Yes
• No
• Observational
• Manipulative

1. A physiologist incubates eggs in the lab at a range of temperatures to see what temperatures produce males and what temperatures produce females.

2. A biologist predicts that shade might influence ground temperature, and therefore turtle sex ratios. He records the sex ratio of turtle hatchlings in shaded and unshaded regions

3. An ecologist predicts turtles grow larger when no predators are around. She places turtles in an experimental pond system where half the ponds have predators and half the ponds have had the predators removed.

4. A climatologist predicts that concentration of CO2 in a city will be negatively correlated with the amount of wind in that city. He collects data and looks at the amount of CO2 in a city as a function of the wind speed in the city.

5. A sociologist conducts a survey in Hawaii to describe people's attitudes about global climate change.

6. A scientist determines the average wind speed, and variation in the amount of wind, in a number of locations to see which locations would be most suitable for wind turbines

Answer/Explanation:

1. Hypothesis-driven? Yes!

Observational or Manipulative? Observational.

We can make this conclusion here that the physiologists' research is hypothesis-driven since we are told he wanted to "see what temperatures produce males and what temperatures produce females." In other words, he wanted to know whether the temperature used in incubators can influence the sex of an egg by means of observation.

2. Hypothesis-driven? Yes!

Observational or Manipulative? Observation.

3.  Hypothesis-driven? Yes!

Observational or Manipulative? Manipulative.

We can make the conclusion that is the ecologist used the manipulative method in her research since she decided to place the turtles in two different types of ponds; one where half the ponds have predators while in the other the pond the predators have been removed. In other words, she manipulated the independent variables.

4. Hypothesis-driven? Yes!

Observational or Manipulative? Observational.

Note, the use of the word, "predicts" in most instances underscores the tone of hypothesis-driven research, hence we can say Yes! And remember, we are told the researcher "collects data", meaning he is merely observing differences that occur naturally.

5. Hypothesis-driven? No!

Observational or Manipulative? Observational.

6. Hypothesis-driven? No!

Observational or Manipulative? Observational.