Comparison of morphology in UW 88–886 (left), <i>P</i>. <i>angusticeps</i> males (CO 100, center), and <i>P</i>. <i>izodi</i> males (TP 89-11-1, right).

<p>Top: Lateral view, specimens scaled to approximately the same cranial height. Note the tall malar region (black bar), prominent maxillary ridges and deep maxillary fossae (white arrows) in UW 88–886 and <i>P</i>. <i>angusticeps</i> compared with <i>P</i>. <i>izodi</i>. Bottom: Dorsal view, specimens scaled to approximately the same cranial width. Note the longer, narrower muzzle in <i>P</i>. <i>angusticeps</i> compared to <i>P</i>. <i>izodi</i>, and again the prominent maxillary ridges and deep maxillary fossae in UW 88–886 and <i>P</i>. <i>angusticeps</i> compared with <i>P</i>. <i>izodi</i>.</p

CT Scans of UW 88–866 in oblique (left) and lateral (right) views.

<p>Again, note the strong maxillary ridges, deep maxillary fossae, strong temporal lines, and tall malar region, distinctive of <i>P</i>. <i>angusticeps</i> males.</p

Comparison of selected morphological features in "small-bodied" <i>Papio</i> species.

<p><b>Notes:</b> Results from one-way ANOVA with Tukey's Honestly Significant Difference post-hoc comparisons for those variables with equal variances and Games-Howell post-hoc comparisons for those variables with unequal variances. Because orbit height, orbit area, and malar height all scale allometrically, the most meaningful comparisons are among taxa of similar body size. The estimated mass for <i>P</i>. <i>angusticeps</i> averages ~21 kg for males and ~15 for females [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0133361#pone.0133361.ref039" target="_blank">39</a>]. <i>P</i>. <i>izodi</i> is estimated at ~20 kg for males and ~15 for females [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0133361#pone.0133361.ref039" target="_blank">39</a>]. The most similar extant taxon in terms of body mass is <i>P</i>. <i>h</i>. <i>cynocephalus</i>, ~23 kg for males and 12.5 kg for females, which is why <i>P</i>. <i>h</i>. <i>cynocephalus</i> is used in the above comparisons. All specimens were pooled regardless of sex in order to increase sample size. For sex-specific values, see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0133361#pone.0133361.t003" target="_blank">Table 3</a>. n.s. = non-significant. Note that <i>P</i>. <i>angusticeps</i> and <i>P</i>. <i>h</i>. <i>cynocephalus</i> are both significantly different from <i>P</i>. <i>izodi</i>, but not from each other. Results for all comparisons are the same if UW 88–886 is included in the <i>P</i>. <i>angusticeps</i> sample. Orbit height defined as the maximum distance between the inferior and superior orbit borders. Orbit width defined as the maximum distance between the lateral and medial orbit borders. Orbit area is defined as orbit width x orbit height. Malar height defined as the distance between orbitale inferior/zygoorbitale and zygomaxillare inferior. Relative malar height defined as malar height/orbit height. <i>P</i>. <i>angusticeps</i> specimens include CO 100, CO 135A/B, CO 101, GV 4040, and HGD 1249. <i>P</i>. <i>izodi</i> specimens include TP 12, SAM 11728, T10, T13, UCMP 125854, UCMP 125855, UCMP 125856, STS 262, T89-11-1, and SWP UN-2. Values for each taxon represent averages. Numbers in parentheses represent estimates. For boxplots with ranges, see also <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0133361#pone.0133361.g004" target="_blank">Fig 4</a> and Table A in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0133361#pone.0133361.s001" target="_blank">S1 Dataset</a>.</p><p>Comparison of selected morphological features in "small-bodied" <i>Papio</i> species.</p

Available craniometric comparisons in <i>P</i>. <i>angusticeps</i>, UW 88–886, <i>P</i>. <i>h</i>. <i>cynocephalus</i>, and <i>P</i>. <i>izodi</i>.

<p>Top Row: Boxplots of orbit height considering UW 88–886 separately (left) and within <i>P</i>. <i>angusticeps</i> (right). Note that <i>P</i>. <i>izodi</i> has significantly taller orbits than both <i>P</i>. <i>angusticeps</i> and <i>P</i>. <i>h</i>. <i>cynocephalus</i>. UW 88–886 has tall orbits compared to other <i>P</i>. <i>angusticeps</i> specimens, but within a reasonable range of expected variation for a species. Middle Row: Boxplots of orbit area (mm²) considering UW 88–886 separately (left) and within <i>P</i>. <i>angusticeps</i> (right). <i>P</i>. <i>izodi</i> has significantly larger orbits than <i>P</i>. <i>angusticeps</i>, but a non-significant difference compared to <i>P</i>. <i>h</i>. <i>cynocephalus</i>. The difference between <i>P</i>. <i>angusticeps</i> and <i>P</i>. <i>h</i>. <i>cynocephalus</i> is also non-significant. UW 88–886 appears to have large orbits compared to other <i>P</i>. <i>angusticeps</i> specimens, but again within a reasonable range of expected variation for a species. Bottow Row: Boxplots of relative malar height considering UW 88–886 separately (left) and within <i>P</i>. <i>angusticeps</i> (right). <i>P</i>. <i>izodi</i> has a significantly shorter malar height compared to <i>P</i>. <i>angusticeps</i> and <i>P</i>. <i>h</i>. <i>cynocephalus</i>, but the difference between <i>P</i>. <i>angusticeps</i> and <i>P</i>. <i>h</i>. <i>cynocephalus</i> is non-significant. UW 88–886 is closest to the average of other <i>P</i>. <i>angusticeps</i> specimens. See also <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0133361#pone.0133361.t002" target="_blank">Table 2</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0133361#pone.0133361.g005" target="_blank">Fig 5</a>.</p

Labeled ct reconstruction of <i>in situ</i> elements.

<p>Left vs. right images are the same specimen rotated 90 degrees with respect to one another. Top vs. bottom images are rendered to show low density tufaceous matrix and to exclude it, respectively. Prior to preparation, all blocks catalogued as AMNH 143612 and AMNH 143640 were CT scanned at Stony Brook University Medical Center. The resulting images allowed us to determine which blocks contained pedal material and where it lay. Surprisingly, only two blocks (one depicted here, the same as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0029135#pone-0029135-g001" target="_blank">figure 1</a>) contained identifiable foot material. As elements were removed, they were labeled with a unique number which is indicated for each bone visible in the bottom images. These numbers were recorded in a 3D pdf files containing images of the <i>in situ</i> bones, like that shown here, as physical preparation was undertaken (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0029135#pone.0029135.s011" target="_blank">Appendix S2</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0029135#pone.0029135.s012" target="_blank">S3</a>). Only pedal elements have been physically removed at this time. Ribs, tibia, fibula, and fragments of an innominate remain embedded.</p

ANOVAs and post hoc tests of distal phalanx variables.

<p>ANOVAs among distal phalanx groups (ungular, tegular, falcular, and grooming phalanges) for indices of distal phalanx shape and an angular measurement (FSA). The columns labeled ungulae and grooming means display the means and variances (in parentheses) for the ungulae and grooming claw groups respectively. Post hoc tests compare ungular and grooming phalanx groups. Comparisons are considered significant at the Bonferroni adjusted alpha of 0.0042. See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0029135#pone-0029135-t003" target="_blank">Table 3</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0029135#s4" target="_blank">Materials and Methods</a> for measurement and group details.</p><p>*GM: “geometric mean” of all linear measurements which is used for size standardization.</p

Basic measurements of AMNH 143612 & 143640, <i>Notharctus tenebrosus</i>.

<p>Measurements (in millimeters) of AMNH 143612 and 143640 elements.</p>a<p>Element abbreviations: Cub, cuboid; Ecc, ectocuneiform; Enc, entocuneiform; Ip, intermediate phalanx; Mec, mesocuneiform; Mt, metatarsal; Pp, proximal phalanx.</p>b<p>Measurement abbreviations: DED, distal end dorsovolar depth; DEW, distal end mediolateral width; L, proximodistal length; MSD, midshaft dorsovolar depth; MSW, midshaft mediolateral width; PED, proximal end dorsovolar depth; PEW, proximal end mediolateral width.</p>c<p>For elements Enc and Cub, these measurements refer specifically to the dimensions of navicular facet and calcaneal facet, respectively.</p>d<p>For elements Enc and Cub, these measurements refer specifically to the dimensions of the Mt1 facet and Mt4-5 facet, respectively.</p><p>*Measurement not applicable.</p><p>**Measurement not obtainable due to breakage.</p

<i>Notharctus tenebrosus</i> AMNH 143612-03, pedal distal phalanx of digit two.

<p>Views are dorsal (top row), medial (second row), ventral (third row), and proximal (bottom row). Left two images are stereopair photographs. Right side images are virtual reconstructions from a microCT scan taken at 0.013 mm resolution.</p

<i>Notharctus tenebrosus</i> AMNH 143612-04, pedal distal phalanx of digit four.

<p>Views are dorsal (top row), medial (second row), ventral (third row), and proximal (bottom row). Left two images are stereopair photographs. Right side images are virtual reconstructions from a microCT scan taken at 0.013 mm resolution.</p

Boxplot of distal phalanx distal shaft width scaled to total phalanx length.

<p>Raw values of shaft width taken at ¾ of the length of the shaft (SW-3/4) are divided by total phalanx length (TPL). SW-3/4 and TPL are demonstrated using illustrations of specimens scaled to the same length. The median specimen from each extant group is illustrated: <i>Tupaia glis</i> represents the falculae group; <i>Callithrix sp.</i>, tegulae; <i>Galago senegalensis</i>, grooming claws; and <i>Saimiri sp.</i>, ungulae. See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0029135#s4" target="_blank">Materials and Methods</a> for measurement descriptions.</p