Temporal change of the three morphometric characters in Siwalik murines.

<p>(A) Ratio of the anterostyle, measured by the length of the minor axis relative to that of the major axis. (B) Acute angle between the anterostyle and the longitudinal axis of the tooth. (C) Acute angle formed by a line connecting the centers of protocone and enterostyle, and the longitudinal axis of the tooth. Symbols as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0076070#pone-0076070-g002" target="_blank">Figure 2</a>. Abbreviations: Pr, Protocone; Ent, Enterostyle. Error bars indicate 95% bootstrap confidence intervals. Note that axes of the wear surface of the anterostyle parallel to the microscope lens. The specimen is <i>Progonomys debruijni</i> (YGSP 7740) in wear stage IV.