Fig. 3

Terrace properties. a: Terrace size as a function of taxon coverage density. The black dot marks the coverage density of the data set for which we terminated terrace tree enumeration before completion (see text). The data point above the plot (in dashed box) represents the largest terrace measured, 10³⁸⁸ trees. b: Resolution (ρ) of the strict consensus tree of a terrace plotted as a function of terrace size. ρ is defined as the ratio of the number of a tree’s bipartitions to the number found in a binary tree of the same size. For two terraces identified in data sets, including the largest (10³⁸⁸ trees) and a terrace consisting of 11,655 trees, we terminated construction of the strict consensus tree before completion