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This study examines dental formation and alveolar emergence in a large cross-sectional sample composed primarily of wild-reared orangutans (N = 89) in order to provide information on the development of the permanent dentition in this hominoid and to address questions of variation in individual tooth formation, between teeth and between individuals. All specimens have been radiographed in lateral aspect and stages of crown and root formation recorded for all teeth. The ranges of crown and root formation of I1(1), C1(1), P4(4), M2(2), and M3(3) have been calculated relative to the stage of M1(1) development within a specific tooth quadrant. Then, for each specimen, BMDP scatterplot and nonparametric statistics have been used to graph changes in stages of these teeth relative to M1(1) stages and to examine relationships between pairs of upper and lower dental counterparts and between teeth of each jaw. Results indicate 1) high correlations between upper and lower tooth pairs and between many of the permanent teeth within individuals, 2) a relatively large range of variability in individual tooth development (multistage ranges relative to M1(1)), 3) greater variation in root development at emergence than earlier reports, and 4) evidence of variability within the sequence emergence pattern of the orangutan.

The degree of maturation of the deciduous dentition and the permanent first molar, as assessed from radiographs, was compared to body weight and carpal development in Macaca nemestrina at birth. All deciduous teeth were present in various stages of development. The permanent molar was represented by 1 to 4 mineralized cusps in 85% of the sample population. A dental maturation score, calculated for each animal, ranged from 12 to 19, with approx. 50% having a score of 17. Compared with the human dentition, that of the neonatal macaque was appreciably more advanced at birth. Carpal development and birth weight were much more variable than dental maturation. Because there appeared to be less variability in tooth development at birth than in the other maturational indicators, tooth formation may offer a better and more accurate estimate of physiological age in this species at this critical time of development.

The Lapita Cultural Complex, radiometrically dated to between 3,600 and 2,500 B.P., is regarded on archaeological evidence as ancestral to modern Austronesian-speaking cultures of eastern Melanesia and Polynesia. To date, there has been a lack of human skeletal and dental material from Lapita sites; thus, the present sample from Mussau Island, although small, offers an opportunity to present some preliminary observations of their importance to Oceanic prehistory. The present analysis, based mainly on teeth, suggests that the Mussau Island Lapita people had slightly closer affinities with Indonesian than with Melanesian populations. These results correspond well with linguistic and archaeological evidence regarding the origin of the Lapita Cultural Complex.

The dental crown morphology and size of 48 male West Nakanai, New Britain, Melanesians is described and compared with other Pacific and Asian dental samples. The West Nakanai dentition is like those of other Melanesians, much less like those of Polynesians and Micronesians, and very dissimilar to teeth of modern and Neolithic Southeast Asians. It is suggested that the origin of the modern Melanesian dental pattern (large but simplified teeth) was probably in Melanesia, not Southeast Asia as the orthodox view of a Hoabinhian-Australmelanesian relation claims.

The rhesus monkey probably has the same sequence of calcification of deciduous teeth as man: central incisor, first molar, lateral incisor, cuspid, and second molar. Initial calcification of the deciduous molar cusps is somewhat similar to that of man.

Evidence suggests that in rhesus monkeys calcification in the mandibular permanent first molar commences much earlier than has been previously reported. This tooth is the first secondary dental element to calcify, as it is in man.