13.27 The graphs below are based on data from an experiment to assess the effects of logging on a squirrel population in British Columbia (“Effects of Logging Pattern and Intensity on Squirrel Demography,” The Journal of Wildlife Management [2007]: 2655-2663). Plots of land, each 9 hectares in area, were subjected to different percentages of logging, and the squirrel population density for each plot was measured after 3 years. The scatterplot, residual plot, and a boxplot of the residuals are shown below.

Does it appear that the assumptions of the simple linear regression model are plausible? Explain your reasoning in a few sentences.