Bernhard Zipfel - Academia.edu (original) (raw)

Papers by Bernhard Zipfel

American Journal of Physical Anthropology, 2017

Curator: The Museum Journal

Fossilized feces, termed coprolites, provide unique information on digestive systems, diets, and ... more Fossilized feces, termed coprolites, provide unique information on digestive systems, diets, and ecosystems of extinct animals, and are potentially useful for palynology, biostratigraphy and preservation of animal and plant remains. Despite this broad utility, scientific enquiry into coprolites has been relatively sparse. We carried out a systematic investigation into 23 significant South African fossil collections of the Evolutionary Studies Institute (ESI), University of the Witwatersrand, Johannesburg, in search of coprolites. This study spanned a temporal range from the Permian to the recent Cenozoic returning approximately 790 known coprolites in the collections. Of these, only four assemblages have appeared in six coprolite‐specific publications. Others have been mentioned to some extent in publications focused on fauna, palynology or simply mentioned that coprolites were present. Clearly, the coprolite collections at the ESI are understudied and require attention with the int...

Journal of Mammalian Evolution

Paleoanthropology, 2016

Homo naledi is a previously unknown species of extinct hominin discovered within the Dinaledi Cha... more Homo naledi is a previously unknown species of extinct hominin discovered within the Dinaledi Chamber of the Rising Star cave system, Gauteng, South Africa. This species is characterized by body mass and stature similar to small-bodied human populations, with a small endocranial volume similar to australopiths. Cranial morphology of H. naledi is unique, but most similar to early Homo species including H. erectus, H. habilis, or H. rudolfensis. While primitive, the dentition is generally small and simple in occlusal morphology. H. naledi has humanlike manipulatory adaptations of the hand and wrist. It also exhibits a humanlike leg and foot. These humanlike aspects are contrasted in the postcrania with a more primitive or australopith-like trunk, shoulder, fingers, pelvis, and proximal femur. Nonetheless, the shared derived features that connect H. naledi with other members of Homo occupy most regions of the H. naledi skeleton and represent distinct functional systems, including locom...

In this preliminary reconstruction of Homo naledi’s gait we begin with the null hypothesis that i... more In this preliminary reconstruction of Homo naledi’s gait we begin with the null hypothesis that it walked similarly to modern humans, as the overall anatomy of this extinct hominin’s lower limb, especially its foot, is mostly modern human-like. We note the following characters as modern-like: dorsally-canting metatarsophalangeal joints facilitating toe-off, locking transverse tarsal joint implying a rigid midfoot during stance, flat subtalar joint limiting ankle pro- and supination, talocrural joint oriented orthogonally to the substrate, valgus knee, thick patellae increasing the moment arm for quadriceps femoris, and well-developed thigh muscle attachment sites throughout the femur. These characters suggest Homo naledi was welladapted to a striding bipedal gait. However, we also note the following less modern-like characters: curved pedal phalanges, low sustentaculum tali and likely a low fundamental longitudinal arch, pronounced tubercular insertion of the pes anserinus tendon on the proximomedial tibia, long femoral neck with a marked medial encroachment of the obturator externus, posteriorly positioned ilium relative to the acetabulum, flared iliac blades, broad lower ribcage, and characters of the lower thoracic vertebrae and lower rib suggesting robust hypaxial muscles. We offer our initial functional interpretations of the cumulative postcranial morphology, which suggests different trunk stabilization from modern humans but is consistent with orthogrady and an obligate bipedal locomotor regime. Given the anatomy of the upper limb, Homo naledi demonstrates coexistence of both bipedalism and climbing adaptations in one hominin taxon.

Journal of Archaeological Science: Reports, 2019

Evolutionary Anthropology, Sep 1, 2018

Journal of Human Evolution, May 1, 2010

Science Advances

The frontal sinuses are cavities inside the frontal bone located at the junction between the face... more The frontal sinuses are cavities inside the frontal bone located at the junction between the face and the cranial vault and close to the brain. Despite a long history of study, understanding of their origin and variation through evolution is limited. This work compares most hominin species’ holotypes and other key individuals with extant hominids. It provides a unique and valuable perspective of the variation in sinuses position, shape, and dimensions based on a simple and reproducible methodology. We also observed a covariation between the size and shape of the sinuses and the underlying frontal lobes in hominin species from at least the appearance of Homo erectus . Our results additionally undermine hypotheses stating that hominin frontal sinuses were directly affected by biomechanical constraints resulting from either chewing or adaptation to climate. Last, we demonstrate their substantial potential for discussions of the evolutionary relationships between hominin species.

Scientific Reports, 2021

Insights into potential differences among the bony labyrinths of Plio-Pleistocene hominins may in... more Insights into potential differences among the bony labyrinths of Plio-Pleistocene hominins may inform their evolutionary histories and sensory ecologies. We use four recently-discovered bony labyrinths from the site of Kromdraai to significantly expand the sample for Paranthropus robustus. Diffeomorphometry, which provides detailed information about cochlear shape, reveals size-independent differences in cochlear shape between P. robustus and Australopithecus africanus that exceed those among modern humans and the African apes. The cochlea of P. robustus is distinctive and relatively invariant, whereas cochlear shape in A. africanus is more variable, resembles that of early Homo, and shows a degree of morphological polymorphism comparable to that evinced by modern species. The curvature of the P. robustus cochlea is uniquely derived and is consistent with enhanced sensitivity to low-frequency sounds. Combined with evidence for selection, our findings suggest that sound perception sh...

South African Journal of Science, 2016

The reported incidence of neoplasia in the extinct human lineage is rare, with only a few confirm... more The reported incidence of neoplasia in the extinct human lineage is rare, with only a few confirmed cases of Middle or Later Pleistocene dates reported. It has generally been assumed that pre-modern incidence of neoplastic disease of any kind is rare and limited to benign conditions, but new fossil evidence suggests otherwise. We here present the earliest identifiable case of malignant neoplastic disease from an early human ancestor dated to 1.8–1.6 million years old. The diagnosis has been made possible only by advances in 3D imaging methods as diagnostic aids. We present a case report based on re-analysis of a hominin metatarsal specimen (SK 7923) from the cave site of Swartkrans in the Cradle of Humankind, South Africa. The expression of malignant osteosarcoma in the Swartkrans specimen indicates that whilst the upsurge in malignancy incidence is correlated with modern lifestyles, there is no reason to suspect that primary bone tumours would have been any less frequent in ancient...

Scientific Reports

Most fossil hominin species are sampled with spatial, temporal or anatomical biases that can hind... more Most fossil hominin species are sampled with spatial, temporal or anatomical biases that can hinder assessments of their paleodiversity, and may not yield genuine evolutionary signals. We use new fossils from the Kromdraai (Unit P) and Drimolen sites (South Africa) to provide insights into the paleodiversity of the Lower Pleistocene robust australopith, Paranthropus robustus. Our focus is the morphology of the temporal bone and the relationships between size and shape (allometry) of the semi-circular canals (SCC), an aspect that has not yet been investigated among southern African australopiths. We find significant size and shape SCC differences between P. robustus from Kromdraai, Drimolen and Swartkrans. This site-related variation is consistent with other differences observed on the temporal bone. P. robustus from Kromdraai Unit P is distinctive because of its smaller temporal bone and SCC, and its proportionally less developed posterior SCC, independently of age and sex. We empha...

Hominin Postcranial Remains from Sterkfontein, South Africa, 1936-1995

This chapter presents description and analysis of the Sterkfontein tibiae and fibulae, which have... more This chapter presents description and analysis of the Sterkfontein tibiae and fibulae, which have not previously been subjected to a careful systematic study. Among these elements, there is a clear range of variation expressed in several functionally relevant features. The distal tibia, StW 358, uniquely exhibits an absence of metaphyseal expansion beyond the talar facet, which appears unique among hominins. If the fibular shaft, StW 356, is associated with StW 358, it could offer additional functional insights into the locomotor repertoire of this individual that might help contextualize this apparently unique trait. Two sets of paired proximal and distal tibiae, StW 514/515 and StW 389/567, suggest possible functional differences in knee and ankle joint configurations, albeit the first is smaller in size than the second. Additional morphological and functional evaluation of variation expressed in many of the features exhibited by these Sterkfontein fossils, along with systematic c...

Journal of Human Evolution, 2022

Homo erectus s.l. is key for deciphering the origin and subsequent evolution of genus Homo. Howev... more Homo erectus s.l. is key for deciphering the origin and subsequent evolution of genus Homo. However, the characterization of this species is hindered by the existence of multiple variants in both mainland and insular Asia, as a result of divergent chronogeographical evolutionary trends, genetic isolation, and interbreeding with other human species. Previous research has shown that cochlear morphology embeds taxonomic and phylogenetic information that may help infer the phylogenetic relationships among hominin species. Here we describe the cochlear morphology of two Indonesian H. erectus individuals (Sangiran 2 and 4), and compare it with a sample of australopiths, Middle to Late Pleistocene humans, and extant humans by means of linear measurements and both principal components and canonical variates analyses performed on shape ratios. Our results indicate that H. erectus displays a mosaic morphology that combines plesiomorphic (australopithlike) features (such as a chimplike round cochlear cross section and low cochlear thickness), with derived characters of later humans (a voluminous and long cochlea, possibly related to hearing abilities)-consistent with the more basal position of H. erectus. Our results also denote substantial variation between the two studied individuals, particularly in the length and radius of the first turn, as well as cross-sectional shape. Given the small size of the available sample, it is not possible to discern whether such differences merely reflect intraspecific variation among roughly coeval H. erectus individuals or whether they might result from greater age differences between them than currently considered. However, our results demonstrate that most characters found in later humans were already present in Indonesian H. erectus, with the exception of Neanderthals, which display an autapomorphic condition relative to other Homo species.