Reified Misconceptions 1 Running head: REIFIED MISCONCEPTIONS Missing Links: How Cladograms Reify Common Evolutionary Misconceptions

Cladograms are tree-like structures devised by evolutionary biologists for conveying patterns of shared ancestry among biological kinds. These representations have become highly popular in science textbooks and science museums, yet most non-biologists have difficulty reading them. Here, I discuss how those difficulties stem from common misconceptions about evolution— misconceptions reinforced not only by what is included in cladograms but also by what is not included. Cladograms routinely omit information about extinction (depicting only the extant species within a taxonomic grouping), biodiversity (depicting only a subset of those species) and variation (depicting species with a single label), and these omissions, while irrelevant to how biologists understand cladograms, likely have cognitive consequences for how non-biologists understand them. I conclude by considering other types of diagrams—circle diagrams, spiral diagrams, and bush diagrams—that depict patterns of shared ancestry with different graphing conventions and may thus be more appropriate than cladograms when their intended audience is non-biologists and their intended purpose is education. Reified Misconceptions 3