Fig. 5.

Graphical representation of the frequency of type I and II biases when quantifying phylogenetic signal using Blomberg et al.’s K and polytomic chronograms (shallow-nodes strategy). The x-axis represents the degree of phylogenetic signal in the traits (λ-transformations). The percentages above the figures refer to the nodes that were randomly collapsed to generate the polytomic chronograms (see Additional file 1: Figure S2 for results derived from an alternative node-collapsing strategy)