Dentition of a Mesolithic Population from Wadi Halfa, Sudan ' DAVID L. GREENEP GEORGE H. EWING3 AND GEORGE J. ARMELAGOS 2 University of Wyoming, Laramie, Wyoming; 3 University of Colorado, Boulder, Colorado; University of Utah, Salt Lake City, Utah ABSTRACT The dentition of a Mesolithic population (8,000-11,000 years old) from Wadi Halfa, Sudan, can be characterized as morphologically complex, massive and relatively free from pathology except that associated with extreme wear. Maxillary incisors show shoveling. All of the maxillary molars show some develop- ment of the hypocone. Supernumerary cusps appear frequently. Almost one-half of the second lower molars observed show distally located third cusps. Over one-half of the maxillary third molars show an extra cusp. A high percentage of mandibular molars show six cusps. Overall the teeth from this population compare favorably in size with those of an Australian aborigine tribe and are slightly larger than the teeth of the Neanderthaloids from Skuhl. The teeth show wear of a degree greater than that found in present day Eskimo or Australian aborigine groups. This data may be intcrpreted as indicating that this Mesolithic group was subjected to rigorous selective pressures favoring large and/or morphologically complex teeth. This pressure was apparently intensive wear, presumably caused by the inclusion of large amounts of grit in the diet through the eating of vegetable food macerated on coarse grinding stones. During the 1963-1964 field season of to the southeast. There was also a large the University of Colorado's Nubian Expe- burial complex in which orientation of the dition, a series of 39 permineralized fossil skulls varied from east to south. The skeletons were discovered by expedition burials were usually flexed, lying on their archaeologists and excavated by the ex- left side, except for one individual resting pedition's three physical anthropologists on his back. (George Armelagos, George Ewing and Preliminary descriptions of these skele- David Greene) . Preliminary analysis by tons have been made elsewhere (Hewes the archaeologist directly responsible for et al., '64; Armelagos et al., '65). Impor- this site, Arthur Saxe ('66), indicates that tant aspects of the skeletal morphology it has Mesolithic affinities and is at least with regard to the dentition as part of a 8,000-1 1,000 years old. functioning morphological complex are The site from which the skeletons were the existence of structures that indicate uncovered, given the designation 6-B-36, heavy masticatory musculature. Tempo- lies between 31 and 35 m above the mean ral lines on the frontal bone are heavily Nile level at Wadi Halfa. This is about marked and most of the skulls show a 151 to 155 m above the mean sea level at pronounced glabellar protrusion which Alexandria and back 2.5 km from the Nile arches and diminishes laterally to a point into what is now desert. Lithic material approximately above the supraorbital fo- recovered from living areas on the site has ramina. These cannot properly be called been included in the Wadi complex of tori but they probably bear a functional Wheat and Irwin ('65) and appears to be relationship to masticatory stress by pro- similar to the Quadan complex described viding struts against lateral stresses in the by Shiner ('65) and Wendorf, Shiner and frontal bone (Ewing, '66). The mandibles Marks ('65). also show features related to heavy mas- Most of the 39 skeletons were deliber- IField work for this study was in part financed ately buried as single and double inter- through National Scienoe Foundation Grants GS-7, GS-286, and GS-557. (Principle Investigator: Dr. C. W. ments and were oriented with their heads Hewes.) AM. J. Pays. ANTHROP.,27: 41-56. 41 42 DAVID L. GREENE, GEORGE H. EWING AND GEORGE J. ARMELAGOS Fig. 1 Typical individual from 643-36 showing marked temporaI lines, gIabelIar pro- trusion, gonial eversion and a massive mandible all indicative of heavy masticatory mus- culature. ticatory musculature. Many show pro- Morphology nounced gOnid eversion and in general The dentition from site 6-B-36can be are massive with heavy bodies and broad characterized as morphologically complex ascending rami. and massive. Almost all individuals, where DENTITION OF A MESOLITHIC POPULATION 43 the observation is possible, show some de- have well developed triangular ridges con- gree of lingual elaboration, or shoveling, necting with the buccal cusp. of the maxillary incisors. Because of post- All nine individuals observed with man- mortem loss and the high degree of dental dibular second premolars have well devel- attrition present in this population, only oped lingual cusps. Five of these exhibit 11 individuals have incisors on which this bilaterally a third distal lingual supernu- trait can be observed. Four of these have merary cusp. In general, these teeth have deciduous incisors; all have distinct labial mesial and distal pits, but the triangular ridges and slight fossae which correspond ridge is not as well developed as in the first premolars. to what Hanihara ('61) calls semishoveled Permanent molars are also morphologi- deciduous teeth. Two of the individuals cally complex. All ten of the individuals with permanent teeth show no indication observed have well developed hypocones on of shoveling; five have what HrdliEka ('20) their maxillary first molars. Second maxil- called trace shoveling (distinct traces of lary molars show more variation. Only one the enamel rim); one has a distinct enamel individual has a well developed hypocone, rim plus a shallow fossa (semishoveled), five show a slight reduction in the size of and one has a marked enamel rim and a the hypocone and three show reduction of well developed fossa (shoveled). Most of the hypocone to a cuspule. Although third the maxillary incisors also have finger-like molars show a wide range of morphologi- projections running on the lingual surface cal variation, (Dahlberg, '45) this sample from the basal tubercle to the incisal edge of 12 individuals is relatively homogene- similar to those on teeth from Jarmo, de- ous. Two individuals have molars with scribed by Dahlberg ('60). only a slight reduction in the hypocone, As would be expected (HrdliEka, '20), two show only a cuspule for a hypocone, shoveling is not as prominent in the man- while one has no hypocone. Seven have dibular incisors. Two out of eight indi- fifth cusps which were probably produced viduals with permanent teeth show very by a splitting of the hypocone. In the three slight development of marginal ridges that cases where both right and left teeth were might be classed as trace shoveling. present, this morphological variant was bi- Lingual elaboration or shoveling con- laterally expressed. In a very large sample tinues into the maxillary and mandibular from historic Nubian populations, this oc- canines. This observation has been made curred bilaterally with a highly significant in other populations (Hanihara, '61 ). Gen- association (0.01 2 P 2 0.001) between erally, both upper and lower canines are left and right sides of the jaw (Greene, monocuspid teeth with noticeable mesial '65). Such mirror imagery in a bilateral and distal lingual marginal ridges which structure suggests that this split hypocone produce the shoveled contour. Of the eight variant has a genetic basis. individuals with maxillary teeth and a sim- Some of the maxillary molars present ilar number with mandibular teeth, none show elaboration of the lingual side of the show noticeable development of cinguli. protocone in the form of cusps, pits and Ten individuals have observable maxil- grooves. Some dental anthropologists feel lary premolars. In both the first and second that the pits and grooves that occur at this premolar, the lingual and buccal cusps are location are not part of the same morpho- almost equally developed with the buccal logical complex as the cusps. They restrict being only slightly larger. Most have well the term Carabelli Trait or Carabelli Cusp marked mesial and distal marginal ridges to the various gradations of cusps that may which are occasionally bisected by a cen- occur (Weidenreich, '37; Hanihara, '63). tral groove. Other dental anthropologists (Korenhof, Mandibular first premolars are bicuspid '60; Kraus, '51) include cusps, pits and with a noticeable lingual cusp. Two indi- grooves in the same complex. Carabelli viduals out of nine have lingual cusps ap- phenomena when iound are not restricted proximating the size of their buccal cusps. to any particular maxillary molar. They All have well marked mesial and distal can occur on any of the maxillary mo- pits and those with larger lingual cusps lars including the second deciduous molar ,44 DAVID L. GREENE, GEORGE H. EWING AND GEORGE J. ARMELAGOS Fig. 2 Mandible showing second premolar with a supernumerary third cusp located dis- tally on its lingual surface. The right third molar, and possibly the second and first as well, has six cusps. (Dietz, '44; Tsuji, '58). In this sample, 4 five distinct cusps. Six of these individuals out of 12 individuals with first maxillary have supernumerary sixth cusps located molars display some elaboration of the lin- between the metaconid and hypoconulid. gual side of the protocone (one pit; one Supernumerary cusps in this location have slight cusp with groove; two medium been termed C6 (Nelson, '38). In the three cusps). Two individuals out of ten show cases where individuals retain both left pits or grooves on their second molars. and right teeth, this variant is bilateral, And 2 out of 12 have slight cusps on their Out of 11 individuals with second man- third molars. dibular molars, five have at least five cusps Cusp number and fissure pattern in with two of these also having supernu- mandibular molars are probably indepen- merary C6 cusps. Out of ten individuals dent morphological and genetic variables with third mandibular molars, five have (J@rgenson, '55; Greene, '65); so their oc- five cusps with three of these also having currence is listed separately.