FIG. 4 in Temporal paralogy, cladograms, and the quality of the fossil record

FIG. 4. — Temporal paralogy and the origin of tetrapods. The possibility of osteolepiforms being ancestors of tetrapods has been reinterpreted based on a parsimony analysis (Ahlberg & Johanson 1998). Among osteolepiforms, the Tristichopteridae appear as the closest relative to the Tetrapoda. The common ancestor of both groups is represented by a paralogous node, and according to temporal hierarchy the relative inclusiveness of each of the sister-groups cannot be decided. As a consequence, the Tetrapoda can be supposed to have occurred before the first appearance of osteolepiforms (Eifelian). There are no arguments to see osteolepiforms as possible ancestors of tetrapods, if this question has any meaning when argued from a parsimony analysis.