The paper "Climate Change on the Checkerspot Butterflies" is a worthy example of an assignment on environmental studies. The purpose of the trial was to study the effect of climate change on the population of two species of checkerspot butterfly. One question asked in the study was whether precipitation variability affected the interaction between host plant and larvae. Another question was whether the habitat loss in relation to dispersal ability caused its extinction. The hypothesis was that extinctions of two populations of the checkerspot butterfly, Euphydryas editha bayensis, were caused by a combination of habitat loss and regional climate change in the form of increasing variability in precipitation (McLaughlin et.al, 2002). The precipitation variability from San Jose and Woodside were evaluated against the population simulations in two different time periods. Linear regression and ordinary cross-validation were used to minimize errors. Simulations were run with bootstrapped samples drawn from two different periods in which each population went extinct. The variables involved were precipitation, adult abundance and year. The similar simulation was obtained by using bootstrapped precipitation data from other relevant time intervals. The control was the starting population sizes in two periods. The results demonstrate that increased precipitation variability likely caused extinctions of two butterfly populations. The variability in the annual precipitation caused a difference in the associable growth cycle of larvae and host plant, which increased the mortality and thus contributed towards extinction. The results indicated the probable reason of population extinction as the severity of weather variance. The result supports the hypothesis as it indicates that habitat loss and climate variability hastened population extinction. The unanswered part of the hypothesis is the effect of temperature and the variance homogeneity.