Campbell Biology 11th Edition by Lisa Urry,Michael Cain,Steven Wasserman,Peter Minorsky,Jane Reece

Exercise 5

How much does Camouflage Affect Predation on Mice by Owls with and without Moonlight D.W. Kaufman hypothesized that the extent to which the coat color of a mouse contrasted with the color of its surroundings would affect the rate of nighttime predation by owls. He also hypothesized that contrast would be affected by the amount of moonlight. In this exercise, you will analyze data from his studies of owl-mouse predation that tested these hypotheses.
How the Experiment Was Done Pairs of mice ( Peromyscus polionotus) with different coat colors, one light brown and one dark brown , were released simultaneously into an enclosure that contained a hungry owl. The researcher recorded the color of the mouse that was first caught by the owl. If the owl did not catch either mouse within 5 minutes, the test was recorded as a zero. The release trials were repeated multiple times in enclosures with either a dark-colored soil surface or a light-colored soil surface. The presence or absence of moonlight during each assay was recorded.
Data from the Experiment
First, make sure you understand how the graphs are set up. Graph A shows data from the light-colored soil enclosure and graph B from the dark-colored enclosure, but in all other respects the graphs are the same. (a) There is more than one independent variable in this graphs. What are the independent variables, the variables that are tested by the researcher Which axis of the graphs has the independent variables (b) What is the dependent variable, the response of the variables being tested Which axis of the graphs has the dependent variable (For additional information about graphs, see the Scientific Skills Review in Appendix F and in the Study Area in MasteringBiology.