Fig. 1From: An analytical upper bound on the number of loci required for all splits of a species tree to appear in a set of gene treesSchematic of a species tree (black) and two gene trees (blue, green). Coalescent events in a gene tree are constrained to occur only once lineages are present in the same population. The red dashed line indicates a species tree bipartition AB |CD, separating species A and B from species C and D. The same bipartition occurs in the blue gene tree; by contrast, the green gene tree does not contain this bipartition, instead containing AD |BCBack to article page