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The article reports that Middle Siwalik sediments exposed at Haritalyangar. India are best known for the diversity of fossil primates that no longer inhabit the Sub-Himalaya, including the late surviving large hominoids Sivapithecus and Indopithecus as well as primitive lemuriform primate. The fossils come from the middle level of the Haritalyangar stratigraphic section, which has a lithostratigraphic profile typical of the Middle Siwaliks of the Potwar Plateau in Pakistan.

While there is gradually accumulating knowledge about molar crown formation and the timing of molar eruption in extant great apes, very little is known about root formation during the eruption process. We measured mandibular first and second molar root lengths in extant great ape osteological specimens that died while either the first or second molars were in the process of erupting. For most specimens, teeth were removed so that root lengths could be measured directly. When this was not possible, roots were measured radiographically. We were particularly interested in the variation in the lengths of first molar roots near the point of gingival emergence, so specimens were divided into early, middle and late phases of eruption based on the number of cusps that showed protein staining, with one or two cusps stained equated with immediate post-gingival emergence. For first molars at this stage, Gorilla has the longest roots, followed by Pongo and Pan. Variation in first molar mesial root lengths at this stage in Gorilla and Pan, which comprise the largest samples, is relatively low and represents no more than a few months of growth in both taxa. Knowledge of root length at first molar emergence permits an assessment of the contribution of root growth toward differences between great apes and humans in the age at first molar emergence. Root growth makes up a greater percentage of the time between birth and first molar emergence in humans than it does in any of the great apes. [ABSTRACT FROM AUTHOR]

Forty-one isolated large hominoid teeth, as well as most of the mandibular and three maxillary teeth associated with a partial skeleton, were recovered from middle Miocene Muruyur sediments near Kipsaramon in the Tugen Hills, Baringo District, Kenya. The isolated teeth were collected as surface finds and the skeleton was excavated in situ at locality BPRP#122 dated between 15·58 Ma and 15·36 Ma. The majority of the teeth recovered at BPRP#122 are referable to a minimum of five individuals of the hominoid Equatorius africanus. Three of the teeth, however, are provisionally assigned to Nyanzapithecus sp. The new hominoids from Kipsaramon add to an increasing inventory of specimens that suggest greater large hominoid taxonomic diversity from the middle Miocene of Kenya than was previously recognized. It is suggested that there are two large-bodied hominoid species present at Mabako, only one of which is assignable toEquatorius. [Copyright &y& Elsevier]

The large hominoid sample from the late Miocene site of Lufeng, China, has been variously claimed to contain either one or two species, but very few metric data in support of either position have been published. We calculate coefficients of variation for the dental remains both for the two presumed species and for the pooled sample as a whole using the summary statistics published by Wu & Oxnard (Wu & Oxnard: American Journal of Primatology 5:303-344, 1983a, Nature 306:258-260, 1983b). These are compared to the same measures of single-sex and combined-sex samples of extant hominoids. We also present metric characterizations of male and female canines of extant great apes, with which we evaluate the gender composition of the Lufeng canine sample. In a two-species alternative, the two presumed species have measures of variability and canine representation that are more compatible with single-sex samples representing males and females, respectively. The pooled dental sample has measures of variability within the ranges of single species of extant great apes. We conclude there is a single large hominoid species represented at Lufeng that is highly sexually dimorphic. The phylogenetic relationships of this species are briefly considered. It is generally primitive in craniodental morhpology and is unlikely to be a member of the Sivapithecus-Pongo clade. [ABSTRACT FROM AUTHOR]

Presents the text of a speech by a lieutenant general of the United States Air Force during the Air Force Association Dinner for the Space and Missile Center in Los Angeles, California in April 19, 1996.

Presents information on the study of large canine teeth in primates and their maintenance and development. Information on evidence found; Methods and materials used; What canines are used for; Results of study.

Age at first molar (M1) emergence is commonly used to infer the general pace of life history in extinct ape and human species. However, there is essentially no information on variation in age at M1 emergence within species to complement the growing body of knowledge on intraspecific variation in life history. Recently reported ages at M1 emergence in five living subjects from the Kanyawara community of Pan troglodytes schweinfurthii in Uganda range from <2.5 to 3.3 years, less than the age from a single deceased Pan troglodytes verus individual from the Taï Forest in Côte d'Ivoire (~3.7-3.8 years), the only other reliable M1 emergence age for wild chimpanzees. Using standard histological methods, we determined ages at death for two wild-shot juveniles of P. t. verus from central Liberia, both with erupting M1s, and estimated their M1 emergence ages at ~4.2-4.4 and ~4.5-4.6 years, substantially later than those of the P. t. schweinfurthii individuals and outside the range of captive chimpanzees (2.1-4.0 years). The combined range of M1 emergence ages from just the small Kanyawara and Liberian chimpanzee samples thus spans nearly the entire range of values known for captive and wild great apes as a whole, a surprising result. While little is known about Liberian chimpanzee life history, data for P. t. verus from the Taï Forest and P. t. schweinfurthii from Kanyawara reveal a somewhat longer average interbirth interval in Kanyawara females. This observation is the reverse of what would be expected given the M1 emergence ages in the two populations and based on the correlation between age at M1 emergence and various life-history traits in primates as a whole. We examine these results with respect to factors impacting the different populations. Supported by the Institute of Human Origins (JK, GTS) and the USA National Science Foundation (TMS). [ABSTRACT FROM AUTHOR]

Three previously described molar teeth attributed to Dryopithecus laietanus were reanalysed with a particular view to determining rates of dentine formation and root extension, and comparing these with new data for Pan troglodytes. Increments of daily root dentine formation close to the granular layer of Tomes (GLT) were imaged in IPS-1781 (M1) and the gradient of increasing rates recorded in zones of 100µm deep to the GLT. The average rate of ~20 measurements per 100µm zone rose from ~2.0 to 2.5µm/day over 200µm deep to the GLT. These were similar to rates measured in P. troglodytes where between 80 and 90 daily increments could occasionally be counted directly within this 200µm zone. These average daily rates were used to reconstruct rates of root extension along the cementdentine junction (CDJ) from the enamel cervix apically. Root extension rates in Dryopithecus rose from 4.1µm per day at the cervix to a maximum of 8.9µm per day at 4828µm root length (equivalent to 4.27 years of M1 formation) and then fell back to 5.1µm per day at 8000µm. The timing of the peak in root extension rate falls within the range observed in 14 P. troglodytes M1s and this in turn corresponds closely with the range of gingival eruption ages documented for captive and free-living Pan. These new data suggest that rates of root extension, even in isolated teeth, may contribute to the ongoing debate about gingival emergence times in living and fossil primates. [ABSTRACT FROM AUTHOR]