Dental size and morphology of precontact Marshall Islanders (Micronesia) compared with other Pacific Islanders

The Marshall Island material is from five locations: the most southern Ebon Atoll; Kwajalein, Majuro, and Ujae atolls in the middle of the archipelago; and the southern Utrik Atoll. All but the Majuro skeletal and dental material was collected by MIW during archaeological excavations between 1993-1997. Crown dimensions and morphological observations were made of the teeth. Shoveling was present on the upper incisors ranging from trace to semi-shovel in 92% of I's and 90% of I's. This was a somewhat higher percentage than for Yap upper incisors, although it was not significant and the degree of shoveling was similar (Harris and others, 1975). The hypercone of the upper molars was always present on M but was absent 17% on M. Carabelli's trait had a low incidence in Oceania and cusps with free apices were rare. In precontact Marshallese, the cusps were present on M 39% which was about 10% higher than reported for Yap (Harris and others, 1975). There was a medium-sized cusp with an independent apex in 11% of M's. Of six dm's 33% had Carabelli's cusps. The Y occlusal groove pattern on M is fairly high in the Pacific (Swindler and others, 1998) and was present 90% of the time, the same figure reported for M in Yap (Harris and others, 1975). The presence of cusp six varied from 3% to 70% on M1 in the Pacific. The latter figure was for Yap which was significantly higher than the 55% found in the Marshallese. M (21%) and M (50%) were more variable. The metrical analysis revealed several significant differences in tooth size among the peoples of Micronesia. The teeth from Palau and Kiribati were usually larger than those from the Marshall Islands and Guam. The teeth of Native Australians are generally the largest in the Pacific The dental evidence suggested that the precontact people living on the small atolls and coral islands in the eastern areas of Micronesia were in many ways dentally similar to the modern day Yapese who were found to be dentally more closely affiliated with people to the east (Polynesia) than to the south (Melanesia) (Harris and others, 1975)

Sex Differences in Permanent Mandibular Tooth Development in Macaca nemestrina

Sex differences in dental maturation prior to and during adolescence in 40 unre­lated Macaca nemestrina were investigated. The data consisted of mixed longitudinal cephalometric films taken at regular intervals during this period. The mandibular premolars and molars presented the following sequence of initial calcification: M1 P3 (M2 P4) M3. In all stages of development, females tended to mature earlier than males, although only 10 of the 22 stages studied were significantly different. Of these, M3 crown completion, M1 cleft formation, and M3 apical closure were the most reliable for discriminating between sexes. The rate of formation of all teeth, with the exception of M3, was faster in the females than the males, and in both sexes the teeth completed their formation during adolescence. It was suggested that these sex differences in dental maturation may be associated with differences in the timing of hormone secretion, i.e., menarche

Metric Trends of the Anterior Teeth in African Monkey

Anterior tooth size trends of four species of African Old World monkeys were examined. Means, ranges, standard deviations, and coefficients of variations were presented for mesiodistal and buccolingual tooth diameters of each species by sex. Hypothesis of equality of means between sexes and between species were tested using a small sample t-statistic. Sexual differences in tooth size were significant for all teeth of Papio cynocephalus and Cercocebus albigena but only for the C4-P.j complex of Cercopithecus spp. These three genera were easily distinguishable on the basis of gross size trends and the two species of Cercopithecus were significantly different except in maxillary incisor size. Both sexes of all three genera showed an enlarged C4-P;1 complex. The demonstration of enlarged canines and sectorial mandibular third premolars in a wide variety of Old World monkeys indicated a common trend within these species