Figure 1 : Divergence of giraffe and okapi from a common ancestor.

From: Giraffe genome sequence reveals clues to its unique morphology and physiology

Figure 1

Using the average pairwise synonymous substitution divergence (dS) estimates between giraffe, okapi and cattle as calibrated by the pecoran common ancestor (27.6 mya), the divergence of giraffe and okapi from a common ancestor is estimated to be 11.5 mya. Okapi image adapted from a photograph by Raul654.