Vegetation cover [%] of control vs. ant plots. The y axis is scaled to y = arcsin
(sqrt (y/100)). Boxes show the median (dividing the box) and the 25% and 75% quantiles;
vertical lines above and below the box indicate observations 1.5 interquartile
ranges from the top vs. the bottom of the box. Outliers (more than three interquartile
ranges away from the box) are shown as dots above and below.