Final answer:
The study analyzed relationships between genetic bottleneck and parasite escape index in butterflies, using Pearson's correlation. The presence or absence of butterfly eyespots was a key independent variable affecting bird predation behavior. Measures of genetic diversity and correlation analyses supported claims about natural selection and trait prevalence.
Step-by-step explanation:
The question concerns a biological study involving Pearson's correlation, butterflies, and their response to predation threat, particularly the role of the eyespot trait. In the study, several variables such as genetic bottleneck indices, the ratio of non-native to native genetic diversity, and the parasite escape index were analyzed. A significant positive correlation between genetic bottleneck and parasite escape indices (Pearson's r = 0.637; p = 0.0025) was observed, suggesting a relationship between these variables within the butterfly population.
Further, the independent variable example in this scenario would likely be the presence or absence of eyespots on the butterflies, as this characteristic is manipulated to observe the birds' responses, which are the dependent variables in the experiment. The data suggests that eyespots make butterflies more visible and therefore likelier to be attacked by predators, leading to natural selection against the trait. Lastly, the notion of parasite escape is considered, where butterflies may avoid carrying parasites, which could influence certain traits' success within the population.