Publications by authors named "Francis Thackeray"

A debate has developed with regard to geological ages of hominin fossils attributed to Australopithecus africanus and Australopithecus prometheus in South African Plio-Pleistocene cave deposits. For the Sterkfontein caves (Members 2 and 4), cosmogenic nuclide isochron (Be/Al) dating has yielded age estimates ranging from 3.4 to 3.

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The origins of , as well as the diversity and biogeographic distribution of early species, remain critical outstanding issues in paleoanthropology. Debates about the recognition of early , first appearance dates, and taxonomic diversity within are particularly important for determining the role that southern African taxa may have played in the origins of the genus. The correct identification of remains also has implications for reconstructing phylogenetic relationships between species of and , and the links between early species and .

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The Kromdraai site in South Africa has yielded numerous early hominin fossils since 1938. As a part of recent excavations within Unit P, a largely complete early hominin calcaneus (KW 6302) was discovered. Due to its role in locomotion, the calcaneus has the potential to reveal important form/function relationships.

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Article Synopsis
  • Reconstruction of australopith locomotion indicates a strong adaptation to bipedalism, with a unique gait compared to modern humans involving more lateral body movement over the stance leg.
  • Recent studies used virtual imaging techniques on Early Pleistocene specimens of Paranthropus robustus to analyze trabecular architecture in the femur, revealing similarities to human bone structure, yet with distinct features.
  • Findings suggest slight differences in gait mechanics between Paranthropus robustus and modern humans, highlighting the need for further research on australopith hip joint dynamics.
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Objectives: The Pleistocene taxon Paranthropus robustus was established in 1938 following the discovery at Kromdraai B, South Africa, of the partial cranium TM 1517a and associated mandible TM 1517b. Shortly thereafter, a distal humerus (TM 1517g), a proximal ulna (TM 1517e), and a distal hallucial phalanx (TM 1517k) were collected nearby at the site, and were considered to be associated with the holotype. TM 1517a-b represents an immature individual; however, no analysis of the potentially associated postcranial elements has investigated the presence of any endostructural remnant of recent epiphyseal closure.

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Studies of the australopith (Australopithecus and Paranthropus) proximal femur have increasingly integrated information from the local arrangement of the cortical and cancellous bone to allow functional-biomechanical inferences on the locomotor behavioral patterns. In Australopithecus africanus and Paranthropus robustus, the cancellous bone organization at the center of the femoral head shows principal strut orientation similar to that of fossil and recent humans, which indicates that australopiths were human-like in many aspects of their bipedalism. However, by combining outer morphology with superoinferior asymmetry in cortical bone thickness at the base of neck and mid-neck, it has been suggested that, while adapted for terrestrial bipedality, australopiths displayed a slightly altered gait kinematics compared to Homo.

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Nursing is pivotal in the social and biological evolution of hominins, but to date, early-life behavior among hominin lineages is a matter of debate. The calcium isotopic compositions (δCa) of tooth enamel can provide dietary information on this period. Here, we measure the δCa values in spatially located microsized regions in tooth enamel of 37 South African hominins to reconstruct early-life dietary-specific variability in , , and early Very low δCa values (<-1.

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Pierre Teilhard de Chardin was a French Jesuit paleontologist, priest, and philosopher. In the figures published in articles in 1943 and 1951, he attempted to draw a "plausible schematic reconstruction of the natural connections between fossil men" and a "phyletic composition of the human group". I draw attention to Teilhard's reference to Eoanthropus ("Piltdown Man") in small print in his figure that was first printed in 1943.

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Objectives: Several studies have investigated potential functional signals in the trabecular structure of the primate proximal humerus but with varied success. Here, we apply for the first time a "whole-epiphyses" approach to analysing trabecular bone in the humeral head with the aim of providing a more holistic interpretation of trabecular variation in relation to habitual locomotor or manipulative behaviors in several extant primates and Australopithecus africanus.

Materials And Methods: We use a "whole-epiphysis" methodology in comparison to the traditional volume of interest (VOI) approach to investigate variation in trabecular structure and joint loading in the proximal humerus of extant hominoids, Ateles and A.

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South African hominin fossils attributed to Australopithecus africanus derive from the cave sites of Makapansgat, Sterkfontein, and Taung, from deposits dated between about 2 and 3 million years ago (Ma), while Paranthropus robustus is known from Drimolen, Kromdraai, and Swartkrans, from deposits dated between about 1 and 2 Ma. Although variation in the premolar root complex has informed taxonomic and phylogenetic hypotheses for these fossil hominin species, traditionally there has been a focus on external root form, number, and position. In this study, we use microtomography to undertake the first comprehensive study of maxillary and mandibular premolar root and canal variation in Australopithecus africanus and Paranthropus robustus (n = 166 teeth) within and between the species.

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Studies of sensory capacities in past life forms have offered new insights into their adaptations and lifeways. Audition is particularly amenable to study in fossils because it is strongly related to physical properties that can be approached through their skeletal structures. We have studied the anatomy of the outer and middle ear in the early hominin taxa Australopithecus africanus and Paranthropus robustus and estimated their auditory capacities.

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We report a Holocene human and animal footprint site from the Namib Sand Sea, south of Walvis Bay, Namibia. Using these data, we explore intratrail footprint variability associated with small variations in substrate properties using a "whole foot" analytical technique developed for the studies in human ichnology. We demonstrate high levels of intratrail variability as a result of variations in grain size, depositional moisture content, and the degree of sediment disturbance, all of which determine the bearing capacity of the substrate.

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The dichotomy between early Homo and Paranthropus is justified partly on morphology. In terms of diet, it has been suggested that early Homo was a generalist but that Paranthropus was a specialist. However, this model is challenged and the issue of the resources used by Australopithecus, the presumed common ancestor, is still unclear.

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Molar crown morphology varies among primates from relatively simple in some taxa to more complex in others, with such variability having both functional and taxonomic significance. In addition to the primary cusps, crown surface complexity derives from the presence of crests, cuspules, and crenulations. Developmentally, this complexity results from the deposition of an enamel cap over a basement membrane (the morphology of which is preserved as the enamel-dentine junction, or EDJ, in fully formed teeth).

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Objective: Our objective is to exploit architectural constraint for the analysis and interpretation of craniofacial form, which we apply here to the reconstruction of the early Homo cranium KNM-ER 1470. We are motivated to perform this study because in the absence of biological criteria our preconceptions are likely to govern our concept of craniofacial form.

Study Design: We reassembled the fragmented parts--left and right halves of the calvaria and the face--according to mammalian craniofacial architectural constraints described by Donald H.

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Stable carbon isotope analyses have shown that South African australopiths did not have exclusively frugivorous diets, but also consumed significant quantities of C4 foods such as grasses, sedges, or animals that ate these foods. Yet, these studies have had significant limitations. For example, hominin sample sizes were relatively small, leading some to question the veracity of the claim for australopith C4 consumption.

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The stable carbon isotope ratio of fossil tooth enamel carbonate is determined by the photosynthetic systems of plants at the base of the animal's foodweb. In subtropical Africa, grasses and many sedges have C(4)photosynthesis and transmit their characteristically enriched 13C/(12)C ratios (more positive delta13C values) along the foodchain to consumers. We report here a carbon isotope study of ten specimens of Australopithecus africanus from Member 4, Sterkfontein (ca.

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