Fig. 5.

Quartile boxplot of (a) log₁₀inner diameter of the sclerotic ring, (b) log₁₀maximum length of the sclerotic ring and (c) log₁₀orbit diameter, showing the differences between nocturnal and diurnal activity patterns. For all three plots, the box represents the quartiles, the extensions represent the data range and the solid line represents the mean, and anova analysis found the differences between the means to be statistically significant (P < 0.001). Archaeopteryx lies within the range of both activity patterns for all three variables.