D. Cristol et al. published results of their studies of two subspecies of dark-eyed juncos in the article "Migratory Dark-Eyed Juncos, Junco Hyemalis, haveBetter Spatial Memory and Denser Hippocampal Neurons than Nonmigratory Conspecifics" (Animal Behaviour, Vol. 66, pp. 317-328). One of the subspecies migrates each year, and the other does not migrate.
Several physical characteristics of 14 birds of each subspecies were measured, one of which was wing length. The following data, based on results obtained by the researchers, provide the wing lengths, in millimeters (mm), for the samples of two subspecies.

a. At the 1% significance level, do the data provide sufficient evidence to conclude that the mean wing lengths for the two subspecies are different? (Note: The mean and standard deviation for the migratory-bird data are 82.1 mm and 1.501 mm, respectively, and that for the nonmigratorybird data are 84.9 mm and 1.698 mm, respectively.)
b. Would it be reasonable to use a pooled t-test here? Explain your answer.
c. If your answer to part (b) was yes, then perform a pooled t-test to answer the question in part (a) and compare your results to that found in part (a) by using a nonpooled t-test.

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Migratory Nonmigratory 84.5 81.0 82.6 821 82.4 83.9 82.8 84.5 81.2 87.1 84.6 85.1 80.5 82.1 82.3 86.3 86.6 83.9 80.1 83.4 81.7 84.2 84.3 86.2 83.0 79.7 878 84.1