Kevin L. Kuykendall

The History and Composition of the Raymond A. Dart Collection of Human Skeletons at the University of the Witwatersrand, Johannesburg, South Africa

The Raymond A. Dart Collection of Human Skeletons (Dart Collection) is housed in the School of Anatomical Sciences at the University of the Witwatersrand, Johannesburg, South Africa, and comprises one of the largest documented cadaver-derived human skeletal assemblages in the world. This collection originated in the early 1920s as a result of the efforts of Raymond Dart and continues to grow. The skeletons included represent varied indigenous and immigrant populations from southern Africa, Europe and Asia. This contribution documents the history of the collection and provides an updated inventory and demographic assessment of this valuable research collection. According to a recent inventory the Dart Collection currently comprises 2,605 skeletons representing individuals from regional SA African (76%), White (15%), Coloured (4%) and Indian (0.3%) populations. A large proportion of the skeletons (71%) represent males. The recorded ages at death range from the first year to over 100 years of age, but the majority of individuals died between the ages of 20 and 70. The Dart Collection has been affected by collection procedures based on availability. All of the cadavers collected before 1958, and large proportions subsequently, were derived from unclaimed bodies in regional South African hospitals. Some details of documentation (age at death, population group) are estimates and some aspects of the collection demographics (sex ratios) do not closely reflect any living South African population. Our inventory and analysis of the Dart Collection is aimed to assist researchers planning research on the materials from this collection.

Permanent tooth calcification in chimpanzees (Pan troglodytes): Patterns and polymorphisms

Tooth calcification is an important developmental marker for use in constructing models for early hominid life history, particularly for its application to the fossil record. As chimpanzees are commonly utilized in interspecific comparisons in such research, this study aims to improve available baseline data for tooth calcification patterns in chimpanzees (Pan troglodytes), and to quantify basic patterns and polymorphisms. We present an analysis of developmental patterns for the left mandibular dentition (I1-M3) based on intraoral radiographs obtained from a cross-sectional sample of chimpanzees (58 males, 60 females) housed at LEMSIP (NYU Medical Center) and Yerkes (Emory University). No significant differences with previous descriptions of the basic sequences of tooth calcification in chimpanzees were found, but variation in such patterns was documented for the first time. In the overall sequence, polymorphisms between the canine and the group (M2 P4 P3) reached significant levels. This is due to the relative delay in canine crown formation compared to other teeth. Differences in the basic sequence between males and females were recorded, but are due to minor shifts in the percentages of occurrence for polymorphic sequences which are common to both genders. Perhaps our most important findings are that a) different polymorphic sequences occur in tooth calcification and tooth emergence in chimpanzees, and b) developmental relationships among teeth fluctuate throughout tooth calcification. Thus, characterizations of dental developmental patterns based on particular stages of development cannot necessarily be extrapolated to other stages without supporting data.

The Makapansgat australopithecine site from a speleological perspective

Abstract Remains of Australopithecus africanus from the Limeworks Cave, Makapansgat, South Africa, are believed to belong mainly to a metre-thick, bone-rich, speleothem layer. The flowstone is one stratum among a sequence of speleothems, muds, silts, sands and fine and coarse breccias, the study of which has evoked some disagreement. The limeworkers’ excavations revealed some stratigraphic relationships but they have obscured others. Partly because of this, controversy surrounds the supposition about whether there are separated depositional basins within the overall site and, if so, whether strata can be securely correlated. This is important because a reconstruction of an overall stratigraphic sequence was used as a basis for a magnetostratigraphic reversal record and by which the site has been tentatively dated. There is qualification and disagreement about the origin of the various flowstones and the actual depositional environment of the muds and silts. Evidence is presented which rules out some previous interpretations. From the point of view of the Australopithecine fossils themselves, it can be said that the calcite matrix in which they were provenanced was a low-energy environment and that the dense bone accumulation of this layer almost certainly did not arise by the action of floods, as previously supposed. The most likely main cause of the dense accumulation was hyena denning activity. It is clear that further work is needed to see how a reliable overall sequence can be established and that closer sampling is required for magnetostratigraphy.

Presence of the maxillary sinus in fossil Colobinae (Cercopithecoides williamsi) from South Africa.

Extant cercopithecoid monkeys, except macaques, are distinguished among primates by their lack of paranasal pneumatization, including the maxillary sinus (MS). Analysis of this structure, widespread among Eutheria, suggests that its loss occurred in the cercopithecoid common ancestor; thus, the presence of the MS in macaques is not strictly homologous to that in other primates. CT analysis of the fossil species Victoriapithecus macinnesi supports this view, demonstrating the lack of the MS in this stem cercopithecoid. Recent evidence, however, has documented the presence of the MS in extinct cercopithecoids from the late Miocene and Pliocene. This study reports on CT examination of two fossil crania attributed to Cercopithecoides williamsi from South Africa, dated in the range, 3.0–1.5 Ma. BF 42a is a complete cranium from Bolts Farm; MP113 is an intact facial skeleton, including the anterior cranial vault, from the Makapansgat Limeworks. Both demonstrate MS presence, unknown in extant colobines and unexpected in most cercopithecoid monkeys. The relative size of the MS of BF 42a is similar to that of extant tropical and subtropical macaques. The presence of sinuses in several extinct colobines suggests that our understanding of the evolutionary history of these primates, and of the MS, is incomplete, and that other fossil cercopithecoids should be examined for this feature. The developmental plasticity exhibited in this feature, indicated by multiple loss and reemergence, provides further evidence that paranasal pneumatization has undergone a complex history of suppression and expression. Anat Rec, 291:1499–1505, 2008.

New species of Cercopithecoides from Haasgat, North West Province, South Africa

Analyses of new cercopithecid fossil specimens from the South African site of Haasgat point to craniofacial affinities with the genus Cercopithecoides. Detailed metric and non-metric comparisons with South African Cercopithecoides williamsi, and other East African Cercopithecoides species, Cercopithecoides kimeui, Cercopithecoides meaveae, Cercopithecoides kerioensis, and Cercopithecoides alemyehui demonstrate that the Haasgat fossils have distinct craniofacial morphology and dental metrics. Specifically, material from Haasgat probably represents one of the smaller Cercopithecoides, differing from the others in its particular suite of features that vary within the genus. It is unique in its more vertical ramus, associated with a relatively lengthened mandibular body. Haasgat Cercopithecoides has a particularly narrow interorbital region between relatively larger ovoid orbits, with articulation of the maxillary bones at a suture above the triangular nasal bones. Furthermore, the maxillary arcade is more rounded than other Cercopithecoides, converging at the M(2) and M(3). The conclusion drawn from this analysis is that the Pleistocene Haasgat fossils are colobines representing a distinct taxon of Cercopithecoides, Cercopithecoides haasgati, thus adding a second species of the genus to southern Africa.

Epiphyseal fusion in Pan troglodytes relative to dental age.

Previous studies on different aspects of chimpanzee growth and development have documented dental eruption and development, long bone and somatic growth, and to a lesser extent, skeletal fusion. Such data are useful in comparative and evolutionary studies of growth and some aspects of life history evolution in apes and early hominids. However, few studies have integrated dental development and other aspects of skeletal development, and none of these have been able to incorporate a large study sample. This study documents dental mineralization and skeletal epiphyseal fusion in a mixed-sex sample of 155 Pan troglodytes skeletons, and aims to: a) document the pattern of dental and skeletal developmental in chimpanzees; b) compare male and female developmental patterns in chimpanzees; and c) compare these chimpanzee developmental patterns to general patterns of dental and skeletal development in published human studies. The analysis of both dental and skeletal development in this sample demonstrates clearly that dental development is complete before the fusion of the many skeletal epiphyses, in contrast to the pattern observed in humans. Age estimates for individuals were calculated using previously published regression equations for dental development and used to estimate fusion ages. These appear to be accurate in that our estimates are similar to published ranges. These data improve our understanding about chimpanzee dental and skeletal development and provide a basis for further comparison between extant apes and humans, as well as those extinct species represented by fossil partial skeletons.

The Dart Deposits of the Buxton Limeworks, Taung, South Africa, and the context of the Taung Australopithecus fossil

ABSTRACT The geologic, environmental, and taphonomic context of the Taung Australopithecus africanus skull has been the subject of speculation and sporadic research since its first publication. In order to refine our contextual knowledge of this important hominin fossil, systematic excavations of the Taung fossil site at the Buxton Limeworks, in the Taung district of what is now the North West Province of South Africa, were conducted from 1988 to 1993. The excavations began on the Hrdlička pinnacle, where Aleš Hrdlička had found fossiliferous deposits in 1925. A separate set of deposits, closer to the reconstructed position of the 1924 Australopithecus discovery and more consistent with the historical record of the Taung discovery, was uncovered on the quarry floor, 42 m southwest of and 6 m lower than the nearest Hrdlička deposits. The fossils of these three distinct deposits, known as the ‘Dart deposits,’ are sparsely distributed, representing different taphonomic conditions and most likely older than most previous discoveries. There are 16 cercopithecid fossils and four bovid fossils, along with eggshell, turtle shell, brachiopods, and reed casts. They provide the most immediate context for the depositional conditions of the Taung Australopithecus juvenile.

A multivariate approach to assess variation in tooth mineralization using free-lived and captive-raised chimpanzees (P. troglodytes).

OBJECTIVES Understanding variation in dental development among primates is important to accurately characterize species-specific sequences and times of tooth formation. Conventional approaches that summarize dental development data (i.e., dental maturity score, DMS) inherently omit information about the full range of variation in raw scores; thus, classic bivariate analyses are limited for exploring patterns of variation in detail. Here we report a new multivariate approach to simultaneously assess all raw dental scores, for all teeth, among all individuals for all groups, thus retaining much greater detail about population-specific patterns of variation. METHODS We scored (0-12) permanent tooth mineralization using radiographs of mandibles of captive-raised known-age chimpanzees (Pan troglodytes; n = 114) and free-lived age-unknown conspecifics (n = 54). As a test of our method we also scored free-lived baboons (Papio anubis, n = 50) because of well-described contrasting patterns of permanent molar initiation between Papio and Pan. Using principal component analysis (PCA), we investigated how crypt, crown and root formation scores covaried with each other in all three genera, and with chronological age in captive chimpanzees. RESULTS PCA successfully captured additional detail about variation among raw scores. Also, compared to DMS, PC1 scores correlated equivalently well with known ages but had lower prediction error. CONCLUSIONS We found different patterns of variation in scores between younger juvenile free and captive chimpanzees but saw no wholesale differences between groups. Pan and Papio showed different patterns of variation, further validating this multivariate approach to visualize, quantify and compare raw dental score datasets among primate species.

Re-examination of the lower stratigraphy in the classic section, limeworks site, Makapansgat, South Africa

At the end of Member 2 times, remnant mammillary-form stalactites in the roof and wall contacts show that an irregular wedge-shaped space existed from the Classic Section out to the Cone area. It was into this space that hyenas and other denning animals were able to gain access from an as yet unfilled Cone area. During the mining operations of the 1920’s, Eitzman (1958) recollects entering an impressive bone breccia resembling a charnel house. We suggest that it is most probable that the Grey Breccia corresponds to his main breccia as only the area on top of Member 2, between the dolomite walls, roof and stalagmite boss has the required volume. It also lies at the end of an incline first dug by the miners, (still in existence), and at the end of which he was able to note some of the deposits. The bone breccias at the same level at the back of the Cone suggest that other dens were created at about this time.As the roof continued to retreat upslope and more material was washed in or fell in from the surface so more sediment was winnowed into the back of the Cone. At some stage this allowed prey animals to enter the Cone area and gain access between the speleothem barrier to the area of the Classic Section. As most Australopithecine fragments came from this breccia, it seems likely that, as with Swartkrans, the hominid fragments are the result of predation. Then as sediments continued to wash into the Cone area, the Classic Section and the back of the Cone became inaccessible for denning purposes.Large speleothem remnants embedded in sediment starting part-way up the Cone shows that a roof continued to exist in this area for some time. In fact, even today, although bits of speleothems can be found in the eroded hardened surface sediments there are few, if any, dolomite blocks. We presume that they were removed along with the upper part of the infilled, cavern along with the country rock as the surface continued to erode.Although it may not be possible to reconstruct a complete strati-graphic sequence involving the whole of the site, we have presented summary of evidence here that shows it is possible to trace stratigraphic relationships from the base of the Ancient Entrance to the top of the Cone and which includes the Grey Breccia and the two other bone breccias. Present work is focussed on completion of a new chronology by comparing our site magnetostratigraphy with the global polarity timescale.The speleothem deposition today in any of the caves of the Makapansgat area, with its annual rainfall of about 700mm, is extremely low. It is commonly recognised by karst geomorphologists (eg, Ford and Williams, 1989) that massive deposits of speleothem are characteristic of humid tropical to semi-tropical karsts. Hence, at the time of their formation some 3 Ma or more ago, the massive speleothem deposits are evidence for a warmer, and certainly a much wetter, climate than that of today.

Analysis of correlations between measures of skeletal development and dental mineralization in Pan troglodytes.

OBJECTIVES This study seeks to assess the relationship between dental mineralization and skeletal development in chimpanzees (Pan troglodytes) and to evaluate the effect that differing numbers of ordinal and continuous variables have on correlation statistics, particularly in comparison with prior human studies. MATERIALS AND METHODS This study evaluated epiphyseal fusion, dental mineralization, and growth in length of long bones using 145 juvenile chimpanzee skeletons housed in osteological collections at the Powell-Cotton Museum, the Museum of Central Africa, and the Adolph Schultz Collection. RESULTS Correlations between multiple epiphyseal fusion sites and dental maturity scores for crown and root mineralization were produced using Pearsons r, Spearmans ρ, and Kendalls τ. Correlation statistics were produced using different subgroups of epiphyseal fusion sites and long bone lengths, and both summary and individual tooth development scores. DISCUSSION Methodological considerations were discussed as differences in sample, measurement scale, and statistical technique had an effect on the outcome of correlations obtained. These results suggest that sampling and methodological differences between studies may affect the interpretation and comparison of correlation results, and that correlation strength differences between extant species must be considered before applying such results to questions in human biology and palaeoanthropology. Even after consideration of such factors, the correlation coefficient values for chimpanzees obtained in this study were generally stronger than those previously published in human studies, and may reflect differences in skeletal and dental developmental patterns between species. Am J Phys Anthropol 158:279-287, 2015.