FIG. 8.—The evolutionary origin and loss of key courtship traits in the genus Desmognathus. Character origins are shown with solid rectangles; losses are shown with open rectangles: tbf ¼ turning back towards the female, tpd ¼ transdermal pheromone delivery (tpd1 and tpd2), ps ¼ pulling and snapping, rfh ¼ rub female head, bas ¼ bite and seize, fm ¼ forelimb movement, and fs ¼ forelimb strokes. Small solid circle denotes branch of origin for adjacent trait box. The time of origin or loss for each trait is bounded by the times at the ends of the branch on which it resides. Time-calibrated phylogeny based on Kozak et al. (2009); time scale shown in millions of years.