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 development 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 protrusion, gonial eversion and a massive mandible all indicative of heavy masticatory musculature.

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 distally 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. With regard C6 supernumerary cusps. The remaining to the first mandibular molar, all 11 indi- five individuals have only four cusps on viduals with relatively unworn cusps show their third mandibular molars. DENTITION OF A MESOLITHIC POPULATION 45

Fig. 3 Maxilla showing incisor shoveling, slight canine shoveling, and left first molar with a small Carabelli Cusp.

Fissure patterns on the mandibular mo- dates from 350 B.C. to 450 A.D. indicates lars can vary from a Y pattern (Dryopithe- that the Mesolithic population displays a cine) to a + (crucilorm) pattern (Hell- higher frequency of supernumerary cusps man, '28). The Y pattern occurs in seven in both maxillary and mandibular molars, out of nine individuals with first molars, a higher frequency of maxillary molars 5 out of 11 with second molars, and none with well developed or just slightly re- out of six with third molars. All of the reduced hypocones, and a higher frequency mainder show cruciform patterns. of shoveling in the maxillary incisors. Two individuals with maxillary third molars and two each with mandibular Odontornetry first, second, and third molars have wrin- Two basic measurements were taken on kled enamel comparable to that found in individual teeth (following Moorrees, '57): the dentition of a Neanderthal child de- (1j Mesiodistal crown diameter: the scribed by Carbonell ('65 j . greatest mesiodistal diameter of the tooth Two individuals show some evidence of crown, measured parallel to the occlusal the protostylid. One has pits on the mesial and labial surfaces. buccal surface of the protoconid of its sec- (2j Buccolingual or labiolingual crown ond mandibular molars which are not in diameter: the greatest distance between contact with the buccal groove. The other the labial and lingual surfaces at right shows a medium-si7ed cusp on the left angles to the mesiodistal crown diameter. third mandibular molar and a pit on the Crown height was not measured since right third mandibular molar. the majority of teeth show extensive oc- Comparing the dental morphology of in- clusal wear. Also, root length measure- cisors and molars of the 6-B-36 population ments were not obtained since most of the with that of a later Meroitic population teeth were still in alveoli. Measurements from the same geographical area which were not taken in any case where wear 46 DAVID L. GREENE, GEORGE H. EWING AND GEORGE J. ARMELAGOS

TABLE 1 Comparison of the morphological complexity of the dentition from the Mesolithic population (64-36) with that found in a Meroitic population

Maxilla Mandible 6-B-36 Meroitic 6-B-36 Meroitic %n %n %n %n I Shoveled 88 (9) 31 (22) 25 (2) - - Normal 12 (2) 69 (48) 75 (6) - - M' 4 100 (10) 69 (33) Mi 6 54 (6) 8 (3) 4- 31 (15) 5 46 (5) 80 (29) 4 12 (4) M2 4 Mz 6 18 (2) 4- 5 2.7 (3) 15 (7) 3+ 4 55 (6) 85 (41) 3 M3 4- Mt 6 30 (3) 3 (1) 3++ 5 20 (2) 50 (17) 3+ 4 50 (5) 47 (16) 3 n, the number of individuals with a specific trait. 4, maxillary molar with well developed hypocone. 4 -, maxillary molar with reduced hypocone. 3 + maxillary molar with hypocone reduced to cuspule. 3 +I+, maxillary molar with split hypocone. 6, manibular molar with six cusps. 5 manibular molar with five cusps. 4: mandibular molar with four cusps. Shoveled, some trace of shoveling in the incisors. Normal, no shoveling in the incisors. The Meroitic data is from Green ('65) and this study did not include data on shoveling in the mandibular incisors. could have produced noticeable error. In '62),Australian Aborigine (Campbell, '25), those measurements taken, the greatest Bantu (Shaw, '31), Pecos Indians and error is probably in the mesiodistal diam- American Whites (Nelson, '38). in order eter of the incisors since occlusal wear of to approximate overall bulk, buccolin- any degree can change this dimension. It gual and mesiodistal mean diameters are should also be noted that, since the num- summed for all teeth in a class (i.e., all ber of measurements in each class is very incisors, all premolars, all molars). No small, no attempt is made to deal with distinction is made between the sexes sample variance aside from listing the since none was made in several of the com- range for each measurement. Only one parative studies. Since these samples vary proportional index was computed - the in number, ranging from 4 to over 100, it Crown Index obtained by dividing the is not practical to apply statistical tests of me siodistal diameter by the buccolingu al significance to the differences observed. and multiplying by 100 to give a measure The mean for the summed measure- of the length-width relationships of the ments of all tooth classes is 256.5 which tooth crowns. is close to the median populational value Measurements were made on a vernier of 256.8 represented by the Skuhl material. sliding caliper accurate to 0.1 mm. All Generally, if the samples are representa- measurements are entered in millimeters. tive, the population from 6-B-36 with a All measurements are from left teeth. value of 262.5 has above average size teeth A comparison of the teeth from 6-B-36 when compared with the size variation with those of other populations gives an present from Middle Pleistocene (Sinan- indication of their relative size. The popu- thropus) to modern populations. Teeth of lations used in this comparison are Sinan- all classes in 6-B-36 are almost as massive thropus (Weidenreich, '37), Skuhl (Coon, as those of the aboriginal Australian popu- DENTITION OF A MESOLITHIC POPULATION 47 lation which has the largest teeth of the Individuals from 6-B-36 fall into three recent populations considered. Overall, the dental age groups : those with deciduous teeth from 6-B-36 are larger than those molars; those with all permanent teeth but from Skuhl. However, anterior teeth from with unerupted third molars; and those 643-36 are smaller than Skuhl anterior with all permanent teeth erupted. Chrono- teeth, while its posterior teeth, especially logical ages for these groups are estimated the mandibular premolars, mandibular mo- following Scott and Symons ('64). lars and maxillary molars, are noticeably Three individuals have deciduous mo- larger. lars. Of these, one represented by the right Attrition half of its mandible shows a completely developed first permanent molar crown Wear was assessed using a scale devel- still unerupted in its crypt, indicating an oped by Brothwell ('63) for molars. This age of from two and one-half to three was modified for the anterior teeth. Cate- years of age. Its deciduous incisors and gories of wear in the premolars and pos- canines were lost post mortem. Its decidu- sibly the canines are equivalent to those ous molars show no indications of wear. in the molars because basically these are The other two individuals in this group cusped teeth. Wear for the incisors is more have permanent first molars, lateral and difficult to assess, but an approximation medial incisors, as well as both deciduous was made which we believe to be adequate. molars, and are somewhere between six

TABLE 2 iMasiElary huccolingual, mesiodistal diameters and crown indices from the Mesolithic population (6-B-36) in millimeters 33-L - M-D - c-I - n I X 11 r X n 1 X I' male 1 - 8.1 1 - 10.3 1 - 78.6 female 2 6.9- 7.1 7.0 2 9.6- 9.7 9.7 2 71.1- 74.0 72.6 all 5 5.5- 8.1 7.3 5 7.2-10.3 9.8 5 71.1- 78.6 75.1 I2 male 1 - 6.8 1 - 8.1 1 - 84.0 female 3 6.5- 7.4 6.9 3 6.9- 7.9 7.6 3 89.0- 96.1 90.8 all 5 6.5- 7.4 6.8 5 6.9- 8.1 7.6 5 84.0- 96.1 90.1 C' male 2 8.4- 8.9 8.7 2 7.2- 7.8 7.5 2 107.7-123.3 115.5 female 2 7.9- 8.7 8.3 2 7.3- 8.0 7.7 2 108.2,108.8 108.5 all 4 7.9- 8.9 8.5 4 7.2- 8.0 7.6 4 107.7-123.3 112.0 P3 male 4 9.1-10.9 10.0 4 7.3- 8.3 7.7 4 118.2-143.8 130.5 female 4 8.1-10.1 9.4 4 7.4- 8.0 7.7 4 108.0-132.4 122.9 all 9 8.1-10.9 9.7 9 7.4- 8.3 7.6 9 108.0-143.8 127.1 P4 male 4 9.0-10.9 10.2 4 7.1- 8.0 7.7 4 112.5-149.3 134.1 female 4 9.1-10.6 9.8 4 6.5- 7.5 7.1 4 135.6-141.3 138.0 all 8 9.0-10.9 10.0 8 6.5- 8.0 7.4 8 112.5-149.3 136.1 M' male 3 12.2-13.0 12.7 3 10.4-12.0 11.4 3 108.3-117.3 111.6 female 4 11.5-12.5 12.2 4 10.1-12.1 11.2 4 102.5-114.7 106.4 all 8 11.3-13.0 12.3 8 10.1-12.1 11.3 8 97.4-117.3 107.2 MZ male 5 12.0-13.2 12.6 5 9.7-11.5 10.5 5 114.8-126.5 120.1 female 4 11.2-12.5 11.9 4 9.7-11.7 10.8 4 104.6-116.8 110.9 all 9 11.2-13.2 12.3 9 9.7-11.7 11.1 9 104.6-126.5 116.0 M3 male 4 10.6-13.2 12.0 4 8.3-10.7 9.4 4 123.4-133.7 127.5 female 6 10.8-13.4 11.7 6 8.3-10.5 9.3 6 117.2-130.1 125.1 all 10 10.6-13.4 11.8 10 8.3-10.7 9.4 10 117.2-133.7 126.0 n, number of teeth measured. r, range. -x, mean. The all category contains at times more than the sum of the males and the females because in some cases individual sex determination was not possible and these are included. 48 DAVID L. GREENE, GEORGE H. EWING AND GEORGE J. ARMELAGOS

TABLE 3 andibular buccolingual, mesiodistal diameters and crown indices from the Mesolithic population (6-B-36)in millimeters B-L M-D c-I - - - n r X n r X n r X 11 male ------female 3 6.2- 6.5 6.3 3 5.4- 5.9 5.6 3 106.8-120.4 112.6 all 4 6.1- 6.5 6.3 4 5.4 6.0 5.7 4 101.7-120.4 109.9 Iz male ------female 2 6.7- 6.7 6.7 2 6.1- 6.4 6.2 2 104.7-109.8 107.2 all 3 6.5- 6.7 6.6 3 6.1- 6.4 6.2 3 104.7-109.8 107.0 C1 male 2 8.3- 8.3 8.3 2 6.9- 8.5 7.7 2 97.6-120.3 108.9 female 1- 7.7 1- 7.1 1 - 108.5 all 4 7.7- 8.3 8.1 4 6.9- 8.5 7.4 4 97.6-120.3 109.7 Pa male 3 8.9- 9.5 9.3 3 7.3- 7.9 7.6 3 112.7-130.2 122.1 female 2 8.3- 8.5 8.4 2 7.4- 7.5 7.5 2 110.7-114.9 112.8 all 5 8.3- 9.5 8.9 5 7.3- 7.9 7.6 5 110.7-130.2 118.4 P4 male 3 9.6-10.2 9.8 3 7.9- 8.1 8.0 3 118.5-125.9 121.9 female 2 8.0- 8.8 8.4 2 6.7- 8.1 7.3 2 111.4-119.4 115.4 all 5 8.0-10.2 9.2 5 6.7- 8.1 7.7 2 111.4-125.9 119.3 MI male 1- 12.7 1 - 12.5 1 - 101.6 female 5 10.1-12.5 11.7 5 10.9-13.2 12.1 5 92.7-100.0 96.2 all 9 10.1-12.7 11.5 9 10.9-13.2 12.1 9 89.2-101.6 95.3 M2 male 4 11.2-13.2 12.0 4 11.1-13.4 12.2 4 95.8-100.1 99.0 female 4 9.5-11.7 11.0 4 9.9-12.2 11.2 4 95.8-100.9 98.0 all 8 9.5-13.2 11.5 8 9.9-13.4 11.8 8 95.8-100.9 98.5 Ma male 4 10.7-12.4 11.7 4 10.9-13.5 12.1 4 89.6-113.8 97.3 female 2 10.9-11.6 11.2 2 11.2-11.3 11.2 2 96.5-104.6 100.5 all 6 10.7-12.4 11.5 6 10.9-13.5 11.8 6 89.6-113.8 98.3 n, number of teeth measured. r, range. -x, mean. The all category contains at times .more than the sum of the males a?d the females because in some cases individual sex determinatlon was not possible and these are included.

TABLE 4 Ranked metric comparison of the summed meun buccolingual and mesiodistal diameters from the Mesolithic population (6-B36) with those from other selected populations

Population Imax Iman Pmax Pman Mmax Mman Sum White 28.4 23.7 31.9 29.9 61.9 62.8 238.6 Pecos 29.5 23.6 33.5 30.9 63.4 65.8 246.7 Bantu 29.6 23.9 32.3 30.6 63.3 64.3 244.0 Skiihl 32.2 26.0 36.0 31.6 65.7 65.3 256.8 6-B-36 31.5 24.8 34.8 33.0 68.2 70.2 262.5 Australian 31.3 25.6 35.4 33.0 70.5 71.4 267.8 Sinanthropus 34.7 27.1 39.4 37.2 68.4 72.3 279.1 Note: In this comparison sample sizes used in determining mean buccolingual and mean mesiodistal diameters for each todth vary for each population listed from 4 I1 (Sinanthropus) to 100 I1 (Pecos Indians). Approximately the same range in sample size exists for the other teeth. The assumption is made in this paper that the means based upon these samples are representative of the populational means. and nine years of age. Both of these show Davies and Pedersen ('55) report that wear on their deciduous molars equal to Eskimo children subsisting on the native Brothwell's scale 4 with dentin exposed diet of meat and fat show wear by the age and linking the cusps. None of their per- of eight to nine that only exposes dentin manent teeth show wear. on the tips of molar cusps in the decidu- DENTITION OF A MESOLITHIC POPULATION 49

TABLE 5 ground on stones to form a coarse meal Wear scale which is then consumed (Meggitt, '57). This type of diet is likely to introduce a 1 - no wear certain amount of abrasive material (stone 2 - enamel abraded particles) aside from hard seeds into mas- tication. The 6-B-36 diet must have con- 3 - dentin barely exposed on cusp tips (or occlusal surface of incisors) tained a greater proportion of abrasive material than the Australian one. Again a 4 -dentin exposure links most of the cusps (occlusal surface of incisors medium worn) possible source of this abrasive material could be the very coarse grinding stones 5 - Most of cusp area enamel worn away only found associated with some of the burials. leaving enamel in deep fissures (occlusal surface of incisors very worn) The third dental age group is much larger than the first two. It consists of 6 - crown worn away all those individuals that have or had (Intermediate grades indicated by +.) their complete sets of permanent dentition erupted. It includes individuals from 17 ous dentition. The children from 6-B-36 years of age and older. Ideally, this group apparently were subjected to greater de- of adults should be analyzed for wear with grees of attrition than the Eskimo chil- regard to age groups. Unfortunately non- dren. In several cases coarse grinding dental information for the assessment of stones were found associated wtih the wear is not available for most of the speci- burials (Saxe, '66). It may be presumed mens. Pubic symphyses are missing or that they were used for macerating vege- shattered. Stresses produced by soil over- table foods and as they were used they burden and geological action at the site produced grit which mixed with the food have opened many cranial sutures. And, and acting as an abrasive wore away the the process of permineralization has in teeth. some cases obscured the degree of cranial Two individuals have all permanent suture fusion. Age could be assessed on teeth but with unerupted third molars that the basis of degree of tooth wear; but, if have completely developed crowns. This these assessments were then used to as- indicates that they are between 12 and 16 sess the rate of wear, the analysis would years of age. One of these shows wear on be circular. Consequently, the adults are his maxillary and mandibular medial in- dealt with as a single group. cisors equal to Brothwell's scale 2 with Since first permanent molars normally abrasion of enamel surfaces. None of his erupt first and are thus exposed to forces other teeth are worn. The other individual of attrition for the longest period of time, shows greater wear. His canines, second the average degree of wear found on an molars and premolars show wear equal to individual's first molars is used to estimate scale 2 while his third molars and incisors the maximum degree of attrition found in show wear equal to scale 3+ with dentin his dentition. Out of 20 adults, 8 (40% ) moderately exposed on occlusal surfaces. show wear equal to Brothwell's scale 4-4+ Beyron ('64), in analyzing dentitions of on their first molars with dentin exposure the Walbiri tribe in Australia, found that linking most of their cusps. Another six 12 out of 24 individuals between the ages (30% ) show wear even greater than this. of 15 and 24 showed no enamel abrasions Summing, 14 out of 20 (70% ) show wear (Broca's Stage I) and that the other 12 which exposes at least enough dentin to showed at most some enamel abrasion but link some cusps. no exposure of dentin (Broca's Stage 11). Beyron ('64) found in a sample of nine Wear found in the 12- to 16-year-old indi- Australian aborigine adults between the viduals from 6-B-36 is greater than that ages of 25 and 44 that four showed only found in a somewhat older Australian enamel abrasion and five (55% ) showed group. wear exposing islands of dentin (Broca's The diet of the Walbiri tribe consists of Stage 111). In a sample of thirteen adults 70 to 80% vegetable food of which most aged 45 and over he found that one (8%) consists of wild seeds. These seeds are showed only enamel abrasion (Broca's 50 DAVID L. CREENE, GEORGE H. EWING AND GEORGE J. ARMELAGOS

Fig. 4 Maxilla showing extreme wear and post-mortem tooth fractures.

Fig. 5 Maxilla showing extreme wear on first and second molars and an unworn left third molar showing five cusps (3++). DENTITION OF A MESOLITHIC POPULATION 51

Stage 11), eleven (84% ) showed some ex- Different degrees of wear in different posure of islands of dentin (Broca’s Stage portions of the dental arcade has at times 111) and only one (8% ) showed complete been used to infer cultural practices. For exposure of the dentin (Broca’s Stage IV). example, some investigators (Brothwell, Comparing the wear found in 6-B-36 ’63) point out that the Eskimos show more with that found in Beyron’s Australian wear on their anterior teeth, incisors, than sample indicates that the lumped adult on their posterior teeth, molars, and interpret this as being the result of the Eski- sample from 6-B-36 has 3 greater propor- mo practice of using their anterior teeth tion of individuals with wear at least ex- extensively for chewing hides and biting posing islands of dentin than Beyron’s 25- thongs. to 44-year-old age group (70% vs. 55% ). In order to compare anterior wear with It is only when Beyron’s group of individ- posterior wear, individuals with one or uals over 45 is compared to the lumped more incisor and one or more first perma- 6-B-36 sample that the proportion of in- nent molar were examined. Permanent individuals with wear at least exposing some cisors erupt between seven and eight years islands of dentin is greater in the Austra- of age and first permanent molars erupt lian group (91c/o vs. 70% ). around six years of age (Anderson, ’62). Assuming that the 6-B-36 sample is not On the average, the length of exposure completely comprised of individuals over to forces of attrition will be similar for 45 years of age, which seems reasonable incisors and molars from the same indi- since Vallois (’37) estimates from other vidual. Mesolithic material that 95.5% of Meso- The distribution of degrees of wear is lithic people were dead by the age of 40, similar with regard to incisors and molars. then the degree of wear found at 6-B-36 This indicates that the individuals found is similar to that found in Beyron’s Aus- at 6-B-36 did not engage in cultural prac- tralian aborigine population. tices that produce differential wear be- Briggs (’55) found in his North African tween anterior and posterior portions of Mesolithic series that 58.8% of his sam- the dentition. ple showed pronounced wear and 23.5% Naturally, wear throughout the denti- showed medium wear throughout their tion is dependent upon the length of time dentitions. Since Briggs’ standards of wear that an individual tooth is subjccted to assessment were not identical to those attrition. Anderson (’62) gives the follow- used in this study a direct comparison ing sequence of average ages of eruption with the wear found in 6-B-36 should not for the permanent teeth. be made. However, Briggs data along with Age in Years Tooth that from 6-B-36 indicates that African 6 First molars Mesolithic populations were subject to a 7 Central incisors considerable amount of dental attrition. 8 Lateral incisors 9 First premolars Anderson (’65) has suggested that an 10 Second premolars analysis of the degree of wear and patterns 11 Canines of attrition in dentitions can at times give 12 Second molars insights into specific cultural practices. He 17-25 Third molars noted erratic wear on thc teeth of the El Those teeth that erupt earliest are exposed Riego and Coxcatlan phases at Tehuacan, to attrition for the longest period of time. Mexico which produced oblique occlusal Grouping the teeth into three eruption surfaces set in different planes. He ex- classes -- Class I: first molars, incisors, plained this as the result of pulling sand first premolars; Class 11: second premo- covered plant material through the teeth lars, canines, second molars; and Class in order to strip off the more edible parts. 111 : third molars - gives the following Most of the wear observed in 6-B-36 is distribution of average wear in these horizontal with little angulation. There is classes for the adult sample. little evidence that this population had Wear on Class I teeth is extensive with specialized cultural practices such as those 18 out of 23 individuals showing wear found at Tehuacan. averaging scale 4 or better. Wear is not as 52 DAVID L. GREENE, GEORGE H. EWING AND GEORGE J. ARMELAGOS

TABLE 6 the occlusal relationship of mandible to Wear found in individuals possessing permanent maxilla. If this is the case, then a Meso- incisors and first molars lithic population with dietary habits tend- Incisors First molars ing toward those found in a Neolithic n n cultural level (the utilization of ground 1-1 + 0 0 vegetable food) might well show the tran- 2-2 + 1 1 sitional distribution of overbite and edge- 3-3 + 2 3 to-edge bite found in 6-B-36. 44+ 6 6 5-5 + 5 2 Abscessing 5+ $4 1 3 Total 15 15 Briggs ('55) and Poitrat-Targowla ('62) n, number of occurrences of wear of a specific suggest that the extreme wear observed in degree out of a sample of 15 individuals. African Mesolithic populations contributes to a very high frequency of apical abscess- TABLE 7 Wear found in different eruption classes ing. Wear exposing the dental pulp opens up a pathway for infection. Out of 29 in- Degrees Class I Class I1 Class I11 dividuals with permanent dentitions either of wear completely erupted or just lacking third n n n molars, eight show alveolar abscessing cen- 1-1 + 0 1 5 tered around one or more root apices. All 2-2 + 2 5 8 3-3 + 3 5 3 of these seem to be the result of a con- 44t 10 6 4 centric spread of infection from the root 5-5 t 4 2 0 apices and would be classified as alveolar 5+ +-6 4 3 0 Total 23 22 20 abscesses by Weinmann and Sicher ('47). Looking at teeth instead of individuals, n, number of individuals with wear in a particular class and of a specific degree. 25 teeth out of 397 observed have apical abscesses. All of these abscessed teeth severe on Class I1 teeth; 11 individuals show wear equal to Brothwell's scale 5 or show wear of less than 4 and 11 show better with most of the occlusal enamel wear greater than 4. Class I11 teeth display worn away. This indicates that, in this the least amount of wear; 16 out of 20 population, teeth do not become abscessed individuals show wear less than 4. Ap- until they are severly worn, supporting parently the longer a tooth is exposed to Briggs' and Poitrat-Targowla's contention. attrition forces, the greater the wear. Pro- However, other factors aside from wear gressive wear such as this, related to in- are also important in the genesis of apical creasing exposure to forces of attrition, abscesses in this population since 55 other might be produced by grit created by teeth show wear of scale 5 or better but grinding vegetable food on coarse stones. they are not associated with abscesses. In- Grit evenly distributed in chewed food dividuals possessing these teeth may not could produce uniform wear on all teeth. have had dental flora that initiate infec- Wear analysis also indicates that most tion through the pulp. of the individuals in this population had Other Mesolithic populations from Africa an edge-to-edge bite. Out of a sample of show as high or higher frequencies of al- nine individuals with both maxillary and veolar abscessing. Briggs ('55) found that mandibular incisors, eight show horizontal 64.5% of 39 individuals in his series had wear on the occlusal surfaces of these one or more abscesses. Poitrat-Targowla teeth while only one has any noticeable ('62) found that 28.7% of sixty-six max- wear on the lingual surface of the mandib- illae showed some abscessing. ular incisors indicating some degree of overbite. Brace ('62) argues that in hu- Caries man evolution the overbite first appears Although the rate of abscessing is high after a group reaches the Neolithic level in this population, the incidence of caries of cultural development which, with its de- is quite low. Only four cases were found. pendence upon cultivated grain, puts more A premolar cavity is on a maxillary masticatory stress on the molars changing right first premolar; it is very large and DENTITION OF A MESOLITHIC POPULATION 53

TABLE 8 Summary of ca7ies incidence

No. of teeth observed Type of tooth No. with caries 61 Maxillary and mandibular incisors 0 110 Maxillary and mandibular premolars 3 42 Maxillary and mandibular canines 0 184 Maxillary and mandibular molars 3 Total 397 apical in nature, eroding away the mesial Other Mesolithic populations also show half of the crown. The three cavities found high frequencies of peridontal diseases. in molars are all interproximal in nature. Briggs ('55) found a frequency of 66.7% One is exceptionally large, eroding away in his series while Poitrat-Targowla ('62) the mesial portion of the occlusal surface found a frequency of 59% at Taforalt. of a left mandibular third molar. Onlv 1% of all the teeth observed Crowdincr- show caries which is slightly lower than Four individuals out of 29 with perma- that observed in other Mesolithic popula- nent dentitions show slight crowding. This tions. Portuguese and other North African was most evident in the anterior portion of Mesolithic populations show frequencies of the dentition, particularly with regard to 3.8% and 3.4% (Clement, '58). Poitrat- Targowla ('62) reports that the Taforalt the incisors. One individual showed an- population had a caries frequency of 5.9%. terior crowding in addition to compres- Above the Mesolithic level of cultural sion in the mandibular molar row pro- development the frequency of caries in- ducing aberrant third molars. Briggs ('55) creases (Brothwell, '60; Clement, '58). found 12.5% (of 37 individuals) crowd- New diets containing soft foods and new ing which is similar to the 13.7% (of 29) bacterial variations probably introduced found in 6-B-36. with the domestication of plants and ani- mals are alleged to have brought about Resorption and evulsion this rapid increase (Brothwell, '60). Actual resorption and restructuring of the mandible and maxilla was extremely PERIDONTAL DISEASE rare, Only two such instances were noted. Intensive tooth wear can expose some One burial had its right mandibular first of the soft tissues of the mouth to infec- molar alveolus completely resorbed. An- tion which may eventually involve alveo- other burial shows partial resorption in lar bone (Brothwell, '63). This seems to connection with a large apical abscess of be borne out by the 6-B-36 dental pathol- the mandibular left first molar. This indi- ogy. Twenty-four out of 28 individuals cates that very few people lost teeth ante where the observation was possible show mortem. some signs of alveolar recession that is In this connection, it is interesting to indicative of alveolar infection. Of these note that there are no instances of evul- with regard to at least one tooth, seven sion of incisors. Cabot Briggs ('55) re- show recession past root bifurcations, five ports that incisor evulsion is common show recession to the root bifurcation, among his North African Mesolithic series. and 12 show recession just below the Ferembach ('62) also notes a high fre- gingival margin. If we assume that all of quency of incisor evulsion in the Taforalt these instances are evidence of peridontal epipaleolithic people. It is apparent that disease, then 85.7% of the population the Mesolithic people at Wadi Halfa dif- were infected. If we exclude the 12 with fered from the other two groups with re- recession, the frequency is still 42.8%. gard to a cultural trait - incisor evulsion. 54 DAVID L. GREENE, GEORGE H. EWING AND GEORGE J. ARMELAGOS

Rotated premolars In 6-B-36, attrition pressures maintained Three individuals show rotated second large teeth and apparently also favored premolars out of 110 premolar observa- dentitions with complicated morphologies. tions. One case shows a 45" rotation in Shoveling is found in the anterior teeth the buccal-mesial direction in a left lower and numerous examples of supernumerary premolar. Another shows a 90" rotation in cusps are found in the posterior teeth. the buccal-mesial direction in a left lower LITERATURE CITED premolar. And another shows a 90" rota- Anderson, J. E. 1962 The Human Skeleton. tion of its upper left second premolar in National Museum of Canada. the lingual-mesial direction. None of these 1965 Human skeleton of Tehuacan. instances are bilateral. Science, 148: 496497. Armelagos, G. J., G. H. Ewing, K. K. Greene and Third molars D. L. Greene 1965 Report of the Physical Anthropology Section University of Colorado Out of 27 reasonably intact sets of den- Nubian Expedition. Kush, 13: 24-27. tition, all have at least one third molar Beyron, H. 1964 Occlusal relations and masti- cation in Australian Aborigines. Acta Odonto- either erupted or still in its crypt. Twelve logica Scandinavica, 22: 597-678. of these individuals have all four third Brace, C. L. 1962 Cultural factors in the evo- molars - 11 completely erupted and one lution of the human dentition. In: Culture and with all four unerupted. Three individuals the Evolution of Man. M. F. A. Montagu, ed. pp. 343-354. Oxford University Press. show one molar in the maxilla. In these Briggs, L. C. 1955 The Stone Age Races of three cases, both mandibular molars are Northwest Africa. In: Bulletin of the American present. Seven individuals had both man- School of Prehistoric Research, No. 18, Harvard dibular molars. Three of these still had University Press, Cambridge, Mass. Brothwell, D. R. 1960 The Palaeopathology of their third molars in crypts. Two individ- Early British Man. J.R.A.S., 91: 318-344. uals had one maxillary molar - one left 1963 Digging up Bones. British Mu- and one right. One individual had a max- seum (Natural History), London. illary left molar and a mandibular left Campbell, T. D. 1925 Dentition and Palate of the Australian Aboriginal. Keith Sheridan molar. And two individuals had only man- Foundation Publications, No. 1, University of dibular left molars. Adelaide, Australia. In all of the above instances, there was Carbonell, V. M. 1965 The teeth of the Nean- no way of assessing whether or not the derthal child from Gibraltar: a re-evaluation. Am. J. Phys. Anthrop., 23: 41-50. missing teeth were congenitally absent Clement, A. J. 1958 Antiquity of caries, Brit. since the other third mular alveoli were Dent. J., 104: 115-123. shattered and missing. However, the avail- Coon, C. S. 1962 The Origin of Races. Knopf, able evidence strongly indicates that the New York. Dahlberg, A. A. 1945 The Changing Dentition incidence of third molar agenesis is quite of Man. J. Am. Dent. Assn., 321: 676-690. low if not zero since the occurrence of 1960 The dentition of the first agricul- bilateral agenesis in either mandible or turists (Jarmo, Iraq). Am. J. Phys. Anthrop., maxilla generally is quite high (Garn et 18: 243-256. Davies, T. G. H., and P. 0. Pedersen 1955 The al., '63). degree of attrition of the deciduous teeth and CONCLUSIONS first permanent molars of primitive and ur- banised Greenland Natives. Brit. Dent, J., 99: It is possible to interpret this data in the 35-43. following way. The Mesolithic population Dietz, V. H. 1944 A common dental morpho- from 6-B-36 was subjected to rigorous se- trophic factor: the Carabelli cusp. J. Am. Dent. Assn., 31: 784-789. lective pressures favoring large and/or Ewing, G. H. 1966 Functional implications of morphologically complex teeth. This pres- the morphology of Mesolithic crania from Nu- sure was apparently intensive wear pre- bia. Paper given at American Association of Physical Anthropologists Meetings, Berkeley, sumably caused by the inclusion of large California. amounts of grit in the diet. Morphologi- Ferembach, D. 1962 La Necropole Epipaleo- cally simple teeth that are large, or teeth lithique de Taforalt: Estude des Souelettes Hu- that are morphologically complex through man: Centre National de la Recherche Scienti- fique, Mission Universitaire et Culturelle Fran- the addition of supernumerary cusps and caise au Maroc. additional ridges and wrinkles provide Garn, S. M., A. B. Lewis and J. H. Vicinus 1963 more material for resistance to attrition. Third Molar Polymorphism and its significance DENTITION OF A MESOLITHIC POPULATION 55

to dental genetics. J. Dent. Res., 42, Supple- Epipaleolithique de Taforalt. Centre National ment no. 6: 1344-1362. de la Recherche Scientifique, Mission Universi- Greene, D. L. 1965 Dentition and the Taxon- taire et Culturelle Francaise au Maroc. pp. omy of Meroitic, X-Group and Christian Popu- 161-371. lations from Wadi Halfa, Republic of the Su- Saxe, A. A. 1966 Social dimensions of mortu- dan. Doctoral Thesis, University of Colorado. ary practices in a Mesolithic population from Hanihara, K. 1961 Criteria for Classification Wadi Halfa, Sudan. Paper given at American of Crown Characters of the Human Deciduous Anthropological Association Meetings, Pitts- Dentition. J. Anthrop. Sac. Nippon, 69: 2745. burgh, Pennsylvania. 1963 Crown characters of the decidu- Scott, J. H., and N. B. Symons 1964 Introduc- ous dentition of the Japanese-American hy- tion to Dental Anatomy. 4th ed. F. and S. Liv- brids. In: Dental Anthropology. D. R. Broth- ingstone Ltd., Edinburgh and London. well, ed. pp. 105-124. Pergamon Press Ltd., Shaw, J. C. M. 1931 The Teeth, The Bony London. Palate and the Mandible in Bantu Races of Hellman, M. 1928 Racial characters in human South Africa. Bale, London. dentition. Proceedings of the American Philo- Shiner, J. L. 1965 Upper Paleolithic and Meso- sophical Society, 67: 157-174. lithic of Nubia. Paper given at the VII Inter- Hewes, G. W., H. Irwin, M. Papworth and A. Saxe national Congress, International Association 1964 A new fossil human population from for Quaternary Research, Boulder, Colorado. the Wadi Halfa Area, Sudan. Nature, 203: 341- Tsuji, T. 1958 Incidence and inheritance of 343. the Carabelli’s cusp in a Japanese population. HrdliEka, A. 1920 Shovel-Shaped Teeth. Am. J. Japanese J. Hu. Gen., 3: 21 (English sum- Phys. Anthrop., O.S. 3: 429-465. mary). Jplrgensen, K. D. 1955 The dryopithecus pat- Vallois, H. V. 1937 La durke de la vie chez tern in recent Danes and Dutchmen. J. Dent. 1’Honime fossile. L’Anthrop., 47: 499-532. Res., 34: 195-208. Weidenreich, F. 1937 The dentition of Sinan- Xorenhof, C. A. W. 1960 Morphological As- thropus Peminensis. Palaeontologica Sinica. pects of the Human Upper Molar. Netherlands, New Series D. No. 1: 1-121. Utrecht. Weinmann, J. P., and H. Sicher 1947 Bone Xraus, B. S. 1951 Carabelli’s anomaly of the and Bones: an introduction to bone biology. maxillary molar teeth. Am. J. Hu. Gen., 3: 348- Mosby, St. Louis. 355. Wendorf, F., J. L. Shiner and A. E. Marks 1965 Meggitt, M. J. 1957 Notes on the vegetable Summary of the 1963-1964 Field Season. Con- foods of the Walbiri of Central Australia. tributions to the Prehistory of Nubia: 9-35. Oceania, vol. XXVIII: pp. 141-145. Fort Burgwin Research Center and Southern Moorrees, C. F. A. 1957 The Aleut Dentition. Methodist University Press. Harvard University Press, Cambridge. Wheat, J. B., and H. T. Irwin 1965 Results of Nelson, C. T. 1938 The teeth of the Indians of the University of Colorado’s Excavations of Pecos Pueblo. Am. J. Phys. Anthrop., 23: 261- Paleolithic and Mesolithic Sites in Nubia. Paper 292. given at the VII International Congress, Inter- Poitrat-Targowla, M. 1962 Pathologie dentaire national Association for Quaternary Research, et maxillaire. In: D. Ferembach, La Necropole Boulder, Colorado.