Figure 1.
Phylogeny and dietary ecology of Ursidae including three-dimensional microwear photosimulations of analyzed taxa.
Phylogeny modified from Krause and colleagues [1] with an update to polar bear origination from Miller and co-authors [2]. The shaded bar highlights the rapid evolutionary radiation of bears, which correlates with climatic and environmental changes. Numbers indicate divergence dates in millions of years. Po, Pliocene; Ps, Pleistocene; H, Holocene. A–F are three-dimensional photosimulations of lower second molars taken at 100× magnification, length and width measurements of photosimulation F correspond to all. A. Ursus maritimus, NMNH 512117; B. Ursus americanus, UF 28436; C. Ursus malayanus, NMNH 151866; D. Tremarctos ornatus, NMNH 271418; E. Ailuropoda melanoleuca, NMNH 259028; F. Arctodus simus, LACMHC 1292.
Figure 2.
Depiction of ursid tooth facets analyzed for dental microwear.
Pictured: Ursus americanus (NMNH 198391), left mandible, buccal view, anterior is to the right. Shading indicates scanned regions. A. Second molar (m2) hypoconulid, mesial facet. B. First molar (m1) protoconid, buccal facet.
Figure 3.
Bivariate plot of complexity (Asfc) vs. anisotropy (epLsar) for lower second molars of ursids.
Polygons enclose data points.
Table 1.
Descriptive statistics of dental microwear attributes used to differentiate diet in bears.
Table 2.
Pairwise differences for microwear attributes of extant ursid lower second molars (Dunn’s procedure).
Table 3.
Pairwise differences of variance between lower second molars of all extant and extinct bears.