Dung beetles are one of the most common types of prey items for burrowing owls. The owls collect bits of large mammal dung and leave them around the entrance to their burrows, where they spend long hours waiting motionless for something tasty to be lured in. A research team wanted to know whether this dung actually attracted dung beetles or whether it had another use, such as to mask the odor of owl eggs from predators (Levey et al. 2004). They added dung to 10 owls’ burrows, randomly chosen, and did not add dung to 10 other owl burrows. The researchers then counted the number of dung beetles consumed by the two types of owls over the next few days. The mean number of beetles consumed in the dung-addition group was 4.8, while the mean number was 0.51 in the control group. The standard deviations for the two groups were 3.26 and 0.89, respectively.

a. What is an appropriate way to test for a difference in these two groups’ beetlecapture rates?

b. Perform this test.