Atlas for PA 2005

[26des12R lab mikropal]
Fig.3.60 (p.64): adult P.pygmaeus from Borneo, A,B upper jaws & dentition. The UC has a mesial & distal vertical groove on the lingual surface. There is a lingual cingulum on the UC, particularly well-developed in females (Hooijer 1948; Swindler 1976).

Both UP3 & UP4 have paracone & protocone, w/ the paracone larger than the protocone. UP3 & UP4 have mesial & distal marginal ridges & mesial & distal crista. There is no mesio-distal developmental groove between the paracone & protocone. Crenulations are present. The palates are broad. C: close-up of the UM1-3. The UM1-3 are more oval in shape than in the chimp or gorilla. There are 4 main cusps, w/ the paracone highest on UM2-3 & the metacone highest on UM1. Swindler (1976) states that the hypocone is always the lowest cusp & may be missing (together w/ the metacone) on UM3. UM3 is the smallest UM & UM2 is either equal to or larger than UM1. Orangutan molars have a sulcus obliquus. While lingual cingula are frequently present, they are less common than in the African apes. Crenulations are present.

Fig.3.61 (p.65): adult P.pygmaeus from Borneo. A: mandible & lower dentition. LP3 is a compressed, sectorial tooth. There is a large protoconid & a smaller metaconid connected by the protocristid. There is a lingual cingulid.. There is a trigonid basin & a talonid basin. Both the protoconid & metaconid are well-developed on LP4. Swindler (1976) reports that entoconids are frequently present. A protocristid is present on LP4, as are trigonid & talonid basins. LM have 5 cusps & the Y5 pattern is evident in this specimen. The metaconid & entoconid are higher than are the buccal cusps. Swindler (1976) reports that the hypoconulid is buccal in position. Buccal cingulids are generally absent. The LM2 is the largest lower molar. B: close-up the left lower cheekteeth.

Fig.3.72 (p.71) modern adult H.sapiens. A; occlusal view of the upper jaws & teeth without the UM3. B: left UC-UM2 of an adult modern human. The specimen is missing the UM3. Each of the upper premolars has 2 main cusps, w/ a groove between them. There is a mesial fossa & a distal fossa at each end of the groove. In modern humans, the lingual & buccal cusps are often subequal in length but the paracone can be taller than is the protocone. UP3 has 2 roots but UP4 has one root. The groove or sulcus on the occlusal surface of UP4 is shallower than on the UP3, which causes the cups to appear shorter on UP4. There is a wrinkled appearance to the occlusal surface of UP4, while the surface is smoother than on UP3. A concavity called the canine fossa is found on the mesial side of UP3 (Hillson 1996:37). The UM1-3 are described having 4 large cusps & 3 roots. The appearance of the occlusal surface is actualy very variable, esp for the UM3. UM1 in this individual has a Caravelli cusp present in the mesio-lingual corner of the tooth & a metaconule. Carabelli cusp is lingual to the protocone. The 2 main buccal cusps are higher than the main lingual cusps. The hypocone is largest in UM1 & smaller in UM2. There is a crista oblique between the metacone & the protocone. In the center of the trigon is the fovea centralis. UM1 is normally the largest tooth on the upper dentition. In UM2, the BL size of the crown is similar to that of UM1 but the MD size is generally less than UM1. In addition, the crown is buccolingually wider in the distal half of the tooth than it’s in the mesial. Ash (1984) writes Carabelli cusp is absent on UM2. UM3 tends to be smaller than UM2 & is very variable in form –ar least partially because of the tooth crowding that is common in modern humans. Often, there is no hypocone & a UM3 may have only three principal cusps. C: bucco-distal view the upper left molars, including UM3.


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