Fig. 3
From: Fossil Horses, Orthogenesis, and Communicating Evolution in Museums

A model to show the difference between orthogenesis (A) and branching (B) speciation (or phylogeny; from MacFadden 1992)
From: Fossil Horses, Orthogenesis, and Communicating Evolution in Museums

A model to show the difference between orthogenesis (A) and branching (B) speciation (or phylogeny; from MacFadden 1992)