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Establishing relationships between soft tissues and bones in living species can inform our understanding of functional adaptations in their extinct kin in the absence of direct data on habitual behaviours. The koala and the wombats are the only surviving species of the vombatiform suborder, and represent the extant phylogenetic bracket for dozens of fossil marsupial species across nine families. Here we present the first quantitative architectural data on the forelimb myology of the koala and common wombat, alongside redescriptions based on physical and digital dissections. Despite obvious contrasts in how their forelimbs are used in arboreal (koala) and fossorial (wombat) functional contexts, overall they showed only minor differences in qualitative and quantitative measures of myology. When the architectural properties of antagonistic pairs of muscle groups crossing each joint were compared, the greatest contrasts were seen in muscles crossing the elbow, where the wombat exhibited greater relative emphasis on forceful elbow extension than the koala, indicative of adaptations for digging. Our findings reinforce the importance of the elbow as a useful system to explore when seeking discrimination between habitual patterns of forelimb use in extinct vombatiform species. [ABSTRACT FROM AUTHOR]

Analysis of 124 rounded fossils, potential bone tools, from the 2.04–1.95 Ma early hominin-bearing Drimolen Main Quarry palaeocave deposits in South Africa were subject to comparative analysis of fossil and bone collections with known taphonomic accumulator/s, actualistic experiments, and comparative analysis relative to published data in the taphonomic literature. From this sample, 51 specimens were identified as bone tools. The inclusion of these specimens raises the number of bone tools identified at Drimolen Main Quarry to 65. The bone tools have a rounded tip and an associated use-wear pattern that is restricted to, and radiates from, this rounded tip. Diaphyseal fragments were the most common raw material selected for tool use. We hypothesise that the raw material was collected from both carnivore kill and natural death sites. The striation patterns, identified though visual comparisons, present on the bone tools comprise parallel, subparallel and diagonal striations which suggests that the tools may have had a multi-use application. The place of bone technology within the South African Earlier Stone Age is also discussed. [ABSTRACT FROM AUTHOR]

Tooth growth and wear are commonly used tools for determining the age of mammals. The most speciose order of marsupials, Diprotodontia, is characterised by a pair of procumbent incisors within the lower jaw. This study examines the growth and wear of these incisors to understand their relationship with age and sex. Measurements of mandibular incisor crown and root length were made for two sister species of macropodid (kangaroos and wallabies); Macropus giganteus and Macropus fuliginosus. Histological analysis examined patterns of dentine and cementum deposition within these teeth. Broader generalisability within Diprotodontia was tested using dentally reduced Tarsipes rostratus – a species disparate in body size and incisor function to the studied macropodids. In the macropodid sample it is demonstrated that the hypsodont nature of these incisors makes measurements of their growth (root length) and wear (crown length) accurate indicators of age and sex. Model fitting finds that root growth proceeds according to a logarithmic function across the lifespan, while crown wear follows a pattern of exponential reduction for both macropodid species. Histological results find that secondary dentine deposition and cementum layering are further indicators of age. Incisor measurements are shown to correlate with age in the sample of T. rostratus. The diprotodontian incisor is a useful tool for examining chronological age and sex, both morphologically and microstructurally. This finding has implications for population ecology, palaeontology and marsupial evolution. • Analysis of incisor growth and wear in diprotodont marsupials. • Discovery that measurement of macropodid incisors informs age and sex. • Histology also finds secondary dentine and cementum inform age. • Generalisability is illustrated using dentally reduced Tarsipes rostratus. • Findings have applications in population ecology and palaeontology. [ABSTRACT FROM AUTHOR]

Most of the diversity of extant southern true seals (Phocidae: Monachinae) is present in the Southern Ocean, but a poor fossil record means that the origin of this fauna remains unknown. Australia represents a large gap in the record bordering the Southern Ocean that could possibly inform on the origins of the extant Antarctic monachines, with most known fossils remaining undescribed. Here we describe the oldest Australian fossil pinniped assemblage, from the Late Miocene to the Early Pliocene of Beaumaris. Two fossils are referrable to Pinnipedia, five (possibly six) to Phocidae and a humerus is referrable to Monachinae. The humerus is not referrable to any extant tribe, potentially representing an archaic monachine. The description of this assemblage is consistent with the Neogene pinniped fauna of Australia being exclusively monachine before the arrival of otariids (fur seals and sea lions). The Beaumaris humerus, along with other Neogene phocids from the Southern Ocean margins, were smaller than their extant Antarctic relatives, possibly driven by longer food chains with less energy efficiency between trophic levels. This suggests that small archaic phocids potentially used the Southern Ocean as a means of dispersal before the arrival of extant Antarctic monachines. [ABSTRACT FROM AUTHOR]

Despite decades of research, the systematics of extinct true seals (Phocidae) is still overly reliant on morphological data from extant taxa. As a result, monk seals (Monachini) have been interpreted as 'archaic' despite an absence of fossil data to support this hypothesis. This has affected systematic hypotheses for extinct phocids, including fossils from Australasia. Recent finds from New Zealand indicate that the first seal fossils described from Australia, two temporal bones from the late Miocene–early Pliocene (6.24–4.35 Ma), need to be revisited. Here we re-describe these temporal bones and find them to represent monk seals. This places the oldest known fossils of this group in the Southern Hemisphere, implying monk seals had a longer history at southern latitudes. Our ancestral state estimation of the temporal bone morphology of monachines indicates that monk seal temporals may be derived, rather than plesiomorphic as has previously been assumed. This suggests that an over-reliance on the morphology of extant true seals may be obscuring the true diversity of both stem- and crown-phocids, and indicates that a rethink of the morphology underlying the taxonomic assessments of fragmentary true seal fossils is needed. [ABSTRACT FROM AUTHOR]

Living true seals (phocids) are the most widely dispersed semi-aquatic marine mammals, and comprise geographically separate northern (phocine) and southern (monachine) groups. Both are thought to have evolved in the North Atlantic, with only two monachine lineages--elephant seals and lobodontins--subsequently crossing the equator. The third and most basal monachine tribe, the monk seals, have hitherto been interpreted as exclusively northern and (sub)tropical throughout their entire history. Here, we describe a new species of extinct monk seal from the Pliocene of New Zealand, the first of its kind from the Southern Hemisphere, based on one of the best-preserved and richest samples of seal fossils worldwide. This unanticipated discovery reveals that all three monachine tribes once coexisted south of the equator, and forces a profound revision of their evolutionary history: rather than primarily diversifying in the North Atlantic, monachines largely evolved in the Southern Hemisphere, and from this southern cradle later reinvaded the north. Our results suggest that true seals crossed the equator over eight times in their history. Overall, they more than double the age of the north-south dichotomy characterizing living true seals and confirms a surprisingly recent major change in southern phocid diversity. [ABSTRACT FROM AUTHOR]

Living true seals (phocids) are the most widely dispersed semi-aquatic marine mammals, and comprise geographically separate northern (phocine) and southern (monachine) groups. Both are thought to have evolved in the North Atlantic, with only two monachine lineages--elephant seals and lobodontins--subsequently crossing the equator. The third and most basal monachine tribe, the monk seals, have hitherto been interpreted as exclusively northern and (sub)tropical throughout their entire history. Here, we describe a new species of extinct monk seal from the Pliocene of New Zealand, the first of its kind from the Southern Hemisphere, based on one of the best-preserved and richest samples of seal fossils worldwide. This unanticipated discovery reveals that all three monachine tribes once coexisted south of the equator, and forces a profound revision of their evolutionary history: rather than primarily diversifying in the North Atlantic, monachines largely evolved in the Southern Hemisphere, and from this southern cradle later reinvaded the north. Our results suggest that true seals crossed the equator over eight times in their history. Overall, they more than double the age of the north--south dichotomy characterizing living true seals and confirms a surprisingly recent major change in southern phocid diversity. [ABSTRACT FROM AUTHOR]

A correction notice for "First monk seal from the Southern Hemisphere rewrites the evolutionary history of true seals" is presented, which is published in the November 11, 2020 issue of the periodical.

The Drimolen Palaeocave System in the 'Fossil Hominid Sites of South Africa' UNESCO World Heritage Site is well known for numerous remains of early hominins such as Paranthropus robustus and early Homo. These hominin fossils, along with bone tools and notably diverse accumulation of non-hominin primates and fauna, have all been excavated from the 'Main Quarry' area of the site where extensive lime-mining took place. Here we report the first radiometric age of 1.712 ± 0.269 Ma for hominin bearing deposits associated with the DNH7 Paranthropus robustus cranium in the Main Quarry area of the site, which is consistent with recent biochronological estimates. This age is similar to recent estimates for Swartkrans Member 1 Hanging Remnant (somewhere between 2.3 and 1.8 Ma) which also contains Paranthropus and early Homo. Simultaneously, we integrate the newly radiometrically dated Main Quarry deposits with a new fossil deposit, the Drimolen Makondo, discovered in 2013, that is situated some 50 m up the hill to the west from the Main Quarry. It has experienced only limited disturbance from mining but much more extensive erosion. Preliminary excavations and analysis have revealed that the Makondo infill is older than the Main Quarry, dating to 2.706 ± 0.428 Ma. Its greater age is confirmed by biochronology. The Makondo thus overlap with the suggested end of deposition of Australopithecus bearing Sterkfontein deposits, although it is yet to yield any hominin remains. These new dates for the two Drimolen Palaeocave System deposits indicates that, contrary to prior age estimates, the Drimolen site as a whole records the critical hominin and faunal turnover in South African palaeocommunities that occurred around 2.3–1.7 Ma. Finally, as the Drimolen Makondo represents a rare example of a pre-2 Ma fossil bearing deposit in the Gauteng exposures of the Malmani dolomite, we also integrate our results into the greater South African record of palaeodeposit formation (most of which occur between ∼2.0 and 1.0 Ma). An analysis of the age of palaeocave infillings across the Malmani dolomite suggests that, as is classically the case with karst, the height within the dolomite is broadly correlated to their age, although with some notable exceptions that are likely related to localised geological features. Our analysis also indicates that most caves have undergone some form of secondary karstification related to a younger phase of cave formation, contrasting with models that suggest the cavities all formed at the same time and that infill is related to erosion and the opening up of cave passages. As such, the reason that few pre-2 Ma deposits have been identified in the Gauteng exposures of the Malmani dolomite is probably because these older caves have been eroded away. Identifying such early caves is critical in understanding whether earlier hominins may have once existed in South Africa or if erosion of older deposits (or an absence of speleogenesis at this time) has made such early periods absent from the geological record. • The first radiometric age (∼ <2.0->1.4Ma) for the DNH7 Paranthropus robustus cranium. • Describes a new older fossil deposit (∼<3.1->2.3 Ma) from Drimolen. • An age for the first documented overlap of two species of Dinofelis in S. Africa. • A new model for cave formation in the Cradle of Humankind (S. Africa). • A model for understanding geological bias in the S. African hominin record. [ABSTRACT FROM AUTHOR]

Abstract The Haasgat fossil-bearing karstic system is situated within the Skurweberg Mountain range in the northeastern portion of the Fossil Hominids of South Africa UNESCO World Heritage Site in South Africa. As is the case for the nearby Gondolin hominin locality, Haasgat occurs in an area of substantial modern topographic relief that contrasts with the low-relief landscape of the southwestern extent of the World Heritage Site surrounding the Blauubank Stream Valley sites (e.g., Sterkfontein, Swartkrans, Kromdraai, Bolt's Farm). This suggests differential landscape formation processes during the Neogene and potentially novel palaeoecosystems and taphonomic processes governing karstic fossil assemblage composition across even a small geographic region. This is particularly critical given the overall paucity of taphonomic data from the region, the substantial cercopithecoid primate assemblage that is uniquely dominated by the basal baboon species Papio angusticeps, and the recent announcement of the first hominin specimen from Haasgat. Here we provide the first comprehensive taphonomic analysis of the Haasgat HGD faunal assemblage that was developed from ex situ calcified sediment blocks in the 1990s. There is direct evidence for biotic activity (e.g., large-bodied carnivores and porcupines) mediating the formation of parts of the HGD faunal assemblage, including at least part of the primate craniodental and postcranial sample. There is minimal evidence for pre-depositional element UV exposure and weathering or winnowing of the assemblage, but there is abiotic distortion and crushing of elements. Our analysis has equally found that taphonomic data from the HGD assemblage is compromised by a modern 'overprint' of damage through mechanical preparation and a lack of documentation generated during sampling, processing, and initial curation. Nearly half the cortical surfaces and many dental specimens in the assemblage exhibit evidence of substantial preparation damage rendering many purported biotic modifications ambiguous or suspect. Element proportions may be artificially skewed towards craniodental specimens and more reflective of block selection and/or selective processing rather than original deposition composition. As a result, the Haasgat HGD sample provides only limited data on the depositional processes mediating karstic assemblage formation in the region, and ultimately serves as a cautionary tale of the impacts of palaeontological sampling strategies on subsequent analysis and research. [ABSTRACT FROM AUTHOR]

Convergence is the tendency of independent species to evolve similarly when subjected to the same environmental conditions. The primitive blueprint for the circulatory system emerged around 700-600 Mya and exhibits diverse physiological adaptations across the radiations of vertebrates (Subphylum Vertebrata, Phylum Chordata). It has evolved from the early chordate circulatory system with a single layered tube in the tunicate (Subphylum Urchordata) or an amphioxus (Subphylum Cephalochordata), to a vertebrate circulatory system with a two-chambered heart made up of one atrium and one ventricle in gnathostome fish (Infraphylum Gnathostomata), to a system with a three-chambered heart made up of two atria which maybe partially divided or completely separated in amphibian tetrapods (Class Amphibia). Subsequent tetrapods, including crocodiles and alligators (Order Crocodylia, Subclass Crocodylomorpha, Class Reptilia), birds (Subclass Aves, Class Reptilia) and mammals (Class Mammalia) evolved a four-chambered heart. The structure and function of the circulatory system of each individual holds a vital role which benefits each species specifically. The special characteristics of the four-chamber mammalian heart are highlighted by the peculiar structure of the myocardial muscle. [ABSTRACT FROM AUTHOR]

Nearly a century of paleontological excavation and analysis from the cave deposits of the Cradle of Humankind UNESCO World Heritage Site in northeastern South Africa underlies much of our understanding of the evolutionary history of hominins, other primates and other mammal lineages in the late Pliocene and early Pleistocene of Africa. As one of few designated fossil repositories, the Plio-Pleistocene Palaeontology Section of the Ditsong National Museum of Natural History (DNMNH; the former Transvaal Museum) curates much of the mammalian faunas recovered from the fossil-rich deposits of major South African hominin-bearing localities, including the holotype and paratype specimens of many primate, carnivore, and other mammal species (Orders Primates, Carnivora, Artiodactyla, Eulipotyphla, Hyracoidea, Lagomorpha, Perissodactyla, and Proboscidea). Here we describe an open-access digital archive of high-resolution, full-color three-dimensional (3D) surface meshes of all 89 non-hominin holotype, paratype and significant mammalian specimens curated in the Plio-Pleistocene Section vault. Surface meshes were generated using a commercial surface scanner (Artec Spider, Artec Group, Luxembourg), are provided in formats that can be opened in both open-source and commercial software, and can be readily downloaded either via an online data repository (MorphoSource) or via direct request from the DNMNH. In addition to providing surface meshes for each specimen, we also provide tomographic data (both computerized tomography [CT] and microfocus [microCT]) for a subset of these fossil specimens. This archive of the DNMNH Plio-Pleistocene collections represents the first research-quality 3D datasets of African mammal fossils to be made openly available. This simultaneously provides the paleontological community with essential baseline information (e.g., updated listing and 3D record of specimens in their current state of preservation) and serves as a single resource of high-resolution digital data that improves collections accessibility, reduces unnecessary duplication of efforts by researchers, and encourages ongoing imaging-based paleobiological research across a range of South African non-hominin fossil faunas. Because the types, paratypes, and key specimens include globally-distributed mammal taxa, this digital archive not only provides 3D morphological data on taxa fundamental to Neogene and Quaternary South African palaeontology, but also lineages critical to research on African, other Old World, and New World paleocommunities. With such a broader impact of the DNMNH 3D data, we hope that establishing open access to this digital archive will encourage other researchers and institutions to provide similar resources that increase accessibility to paleontological collections and support advanced paleobiological analyses. [ABSTRACT FROM AUTHOR]

Background The teaching of human head, neck and orbital anatomy forms a critical part of undergraduate and postgraduate medical and allied health professional training, including optometry. While still largely grounded in cadaveric dissection, this method of instruction is constrained in some countries and regional areas by access to real human cadavers, costs of cadaver bequest programmes, health and safety of students and staff and the shortage of adequate time in modern curricula. Many candidates choosing a postgraduate pathway in ophthalmological training, such as those accepted into the Royal Colleges of Ophthalmology in the UK, Australia and New Zealand programmes and the American Academy of Ophthalmologists in the USA, are compelled as adult learners to revise or revisit human orbital anatomy, ocular anatomy and select areas of head and neck anatomy. These candidates are often then faced with the issue of accessing facilities with dissected human cadaveric material. Methods In light of these difficulties, we developed a novel means of creating high-resolution reproductions of prosected human cadaver orbits suitable for education and training. Results 3D printed copies of cadaveric orbital dissections (superior, lateral and medial views) showing a range of anatomical features were created. Discussion These 3D prints offer many advantages over plastinated specimens as they are suitable for rapid reproduction and as they are not human tissue they avoid cultural and ethical issues associated with viewing cadaver specimens. In addition, they are suitable for use in the office, home, laboratory or clinical setting in any part of the world for patient and doctor education. [ABSTRACT FROM AUTHOR]

The relationship between ecology and morphology of the limbs in living placental mammals is well established and has been used to infer aspects of palaeobiology for many extinct species. However, few studies have applied these principles to extinct marsupials. Palorchestids are a poorly understood extinct family of megafaunal marsupials of particular interest due to their highly robust and unusual limb morphology. Using a comparative sample of humeri and femora from living mammals potentially analogous to palorchestids, we applied three-dimensional geometric morphometric techniques in a phylogenetic comparative framework. We established that humerus and femur shape in living species showed significant associations with size, phylogeny, and substrate use, and found a weak association between humeral shape and diet. We then examined patterns in morphological disparity, modularity, covariance and morphospace occupation in palorchestids relative to comparative living mammals as well as their closest extinct marsupial relatives. We found palorchestid femora to be unremarkable in shape, while their overall and proximal humeral morphology were strongly divergent from all other mammals sampled. Over their evolutionary history, palorchestid distal humeri increasingly resembled those of mammals adapted for tearing and hook-and-pull digging, while other analyses showed various arboreal-like and fossorial-like affinities in humeral shape. Our findings indicate strong asymmetric selection acting on the fore- and hindlimbs in palorchestids, and their unique combination of shape traits suggests they used their forelimbs in a specialised manner that has no direct equivalence either with their extinct relatives or among other mammals alive today. [ABSTRACT FROM AUTHOR]

The current study considers the osteological morphology of the giraffe ( Giraffa camelopardalis) vertebral column, with emphasis on evaluating both the adaptive and constraining features compared with other ungulates as a heuristic example in understanding evolutionary processes. Vertebral columns of giraffes varying in age from calf to adult were studied in order to understand the potential evolutionary scenarios that might have led to the modern phenotype. Data from the giraffe sample were then compared with the results from several other ungulate species, including the okapi and two species of camelids that also have visibly elongated necks. Our results show that the elongated neck of the modern giraffe appears to specifically result from evolutionary changes affecting the seven cervical vertebrae, independent of the remainder of the vertebral column. The cervical vertebrae comprise over half of the length of the total vertebral column in the giraffe. The increases in cervical vertebrae lengths also appear to be allometrically constrained, with alterations in the overall length of the neck resulting from the elongation of the entire cervical series, rather than from a single vertebra or subset of vertebrae. We place our results in the context of hypotheses concerning the origin and evolution of the giraffe neck, and the evolution of long necks in a broader sense. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155, 736–757. [ABSTRACT FROM AUTHOR]

Abstract: Occasional excavation of in situ and ex situ deposits at the formerly mined Gondolin paleocave system has yielded large and diverse samples of Plio-Pleistocene faunas, including isolated hominin and non-hominin primate remains. In 2003, new excavations into naturally decalcified, in situ sediments near the GD 1 datum point near the northwest corner of the cave system were undertaken. This paper describes the recovered faunal remains, taphonomy of the assemblage, and the geological and paleomagnetic context of the GD 1 deposits. The deposits represent a series of inter-stratified speleothem, in-washed sediments and talus deposits we suggest date to a time period prior to, and just after, the Olduvai normal-polarity event at around 1.7–1.8Ma. Surface sediments and clasts were introduced into the cave by rain water runoff entering a vertically-oriented entrance that had formed along a rift in the area of GD 1. The faunal assemblage consists primarily of fragmentary diaphyseal fragments and isolated teeth. Taxonomically, the small collection of specifically identifiable bovid and equid fossils is generally consistent with remains previously excavated from in situ deposits in the Gondolin paleocave system (GD 2) and dated to around 1.8Ma; however, the depositional histories of these two assemblages from Gondolin are remarkably different. The preservation and relative proportions of recovered skeletal elements at GD 1 is consistent with these materials having been initially accumulated outside the karstic system near the vertical cave entrance, and then later hydrologically sorted and deposited inside the cave. The sporadic to continuous water flow into the northwest corner of the cave system during the Pleistocene gradually decalcified the excavated fossilbearing breccias and further modified the composition and spatial distribution of the fossil assemblage by introducing potentially younger deposits and skeletal materials. This study highlights the variation in taphonomic processes that can occur within a single cave system, and the complex pre- and postdepositional geological and hydrological processes that can influence the taphonomic history of South African Plio-Pleistocene karstic fossil assemblages. [Copyright &y& Elsevier]

Abstract: Speleological, paleomagnetic, mineral magnetic, and biochronological analyses have been undertaken at the Gondolin hominin-bearing paleocave, North West Province, South Africa. Two fossiliferous but stratigraphically separate sequences, GD2 and GD1/3, which were once part of a large cavern system, have been identified. Although some comparative paleomagnetic samples were taken from the GD 1, 3, and 4 localities that are currently under investigation, the research presented here focuses on the fossil-rich, in situ deposits at locality GD 2, excavated by E.S. Vrba in 1979. The GD 2 deposits are dominated by normal-polarity calcified clastic deposits that are sandwiched between clastic-free flowstone speleothems. The lower flowstone has a sharp contact with the red siltstone deposits and is of reversed polarity. The capping flowstone shows a change from normal to reversed polarity, thereby preserving a polarity reversal. While the paleomagnetic work indicates that the GD 2 fossil material was deposited during a normal-polarity period, the shortness of the sequence made matching of the magnetostratigraphy to the geomagnetic polarity time scale (GPTS) impossible without the aid of biochronology. While lacking multiple time-sensitive taxa, the recovery of specimens attributable to Stage III Metridiochoerus andrewsi is consistent with a deposition date between 1.9 and 1.5Ma. A comparison of the magnetostratigraphy with the GPTS therefore suggests that the fauna-bearing siltstone of GD 2 date to the Olduvai normal-polarity event, which occurred between 1.95 and 1.78Ma, and that the reversal from normal to reversed polarity identified in the capping flowstone dates to 1.78Ma. The main faunal layers therefore date to slightly older than 1.78Ma. Deposits from the GD 1 locality are dominated by reversed directions of magnetization, which show that this deposit is not of the same age as the faunal layers from the GD 2 locality. [Copyright &y& Elsevier]

The article discusses the Emeritus Professor R. H. Anderson confutes the existence of the so-called helical ventricular myocardial band. It states that the model of heart anatomy based on the helical ventricular myocardial band (HMVB) which has been validated in several aspects of heart pathophysiology and is involved in clinical procedures in cardiology and heart surgery like heart failure.

True seals (phocids) have achieved a global distribution by crossing the equator multiple times in their evolutionary history. This is remarkable, as warm tropical waters are regarded as a barrier to marine mammal dispersal and—following Bergmann's rule—may have limited crossings to small‐bodied species only. Here, we show that ancestral phocids were medium sized and did not obviously follow Bergmann's rule. Instead, they ranged across a broad spectrum of environmental temperatures, without undergoing shifts in temperature‐ or size‐related evolutionary rates following dispersals across the equator. We conclude that the tropics have not constrained phocid biogeography. [ABSTRACT FROM AUTHOR]

Extant African papioninans are distinguished from macaques by the presence of excavated facial fossae; however, facial excavation differs among taxa. Mangabeys (Cercocebus , Rungwecebus , and Lophocebus) exhibit fossae that invade the zygomatic forming pronounced suborbital fossae (SOFs). Larger-bodied Papio, Mandrillus, and Theropithecus have lateral rostral fossae with minimal/absent suborbital fossae. Because prior studies have shown that mangabeys exhibit adaptations to anterior dental loading (e.g., palatal retraction), it is plausible that mangabey SOFs represent structural accommodation to masticatory-system shape rather than facial allometry, as commonly hypothesized. We analyzed covariation between zygomaxillary-surface shape, masticatory-system shape, and facial size in 141 adult crania of Macaca fascicularis , Papio kindae , Cercocebus , and Lophocebus. These taxa represent the range of papionin SOF expression while minimizing size variation (narrow allometry). Masticatory-system landmarks (39) registered palate shape, bite points, masticatory muscle attachments, and the temporomandibular joint. Semilandmarks (450) captured zygomaxillary-surface shape. Following Procrustes superimposition with semilandmark sliding and principal components analyses, multivariate regression was used to explore allometry, and two-block partial least-squares analyses (within-configuration and separate-blocks) were used to examine covariation patterns. Scores on principal components 1–2 and the first partial least-square (PLS1) separate mangabeys from Macaca and Papio. Both zygomaxillary-surface shape and masticatory-system shape are correlated with size within taxa and facial morphotypes; however, regression distributions indicate morphotype shape differences are non-allometric. PLS1 accounts for ∼95% of shape covariance (p < 0.0001) and shows strong linear correlations (r-PLS = ∼0.95, p < 0.0001) between blocks. Negative PLS1 scores in mangabeys reflect deep excavation of the suborbital malar surface, palatal retraction, and anterior displacement of jaw adductor muscles and the temporomandibular joint. Neither PC1 nor PLS1 scores ordinate specimens by facial size. Taken together, these results fail to support the allometric hypothesis but suggest that mangabey zygomaxillary morphology is closely linked with adaptations to hard-object feeding. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Shallow-Water Habitats as Sources of Fallback Foods for Hominins," by R. Wrangham, D. Cheney, R. Seyfarth and E. Sarmiento.

Abstract: Fossils of early Homo and Paranthropus have been recovered from several sites in southern Africa. Unfortunately, their precise age has historically been difficult to assess, hampering the reconstruction of their relationships to each other and to fossils from eastern Africa. Multi-dating strategies combining biochronological, archaeological, palaeomagnetic, electron spin resonance (ESR) and uranium series techniques are now clarifying their age. The following sequencing of sites is suggested: Swartkrans Member 1 (∼2.0Ma), Gondolin (∼1.8Ma), Kromdraai (1.8–1.7Ma), Sterkfontein M5A (1.8–1.4Ma), Swartkrans M2 (1.7–1.1Ma), Sterkfontein M5B (1.4–1.1Ma), Sterkfontein M5C (1.3–0.8Ma), Swartkrans M3 (∼1.0–0.6Ma). The position of Coopers D and Drimolen is difficult to access because they only have faunal age ranges (1.9–1.6Ma). ESR suggests mixing is a potential major problem in multi-generational sites. The oldest southern African representatives of early Homo and Paranthropus occur around 2.1–1.9Ma in Swartkrans Member 1 and are recorded almost continuously in the palaeocave deposits until around 1.0–0.6Ma in Swartkrans Member 3. Currently, these data suggest that Paranthropus and Homo first occur significantly later in the southern African record than the eastern African record. Moreover, Paranthropus persists much later in southern Africa than in eastern Africa. [Copyright &y& Elsevier]

Joint mobility is a key factor in determining the functional capacity of tetrapod limbs, and is important in palaeobiological reconstructions of extinct animals. Recent advances have been made in quantifying osteological joint mobility using virtual computational methods; however, these approaches generally focus on the proximal limb joints and have seldom been applied to fossil mammals. Palorchestes azael is an enigmatic, extinct ~1000 kg marsupial with no close living relatives, whose functional ecology within Australian Pleistocene environments is poorly understood. Most intriguing is its flattened elbow morphology, which has long been assumed to indicate very low mobility at this important joint. Here, we tested elbow mobility via virtual range of motion (ROM) mapping and helical axis analysis, to quantitatively explore the limits of Palorchestes' elbow movement and compare this with their living and extinct relatives, as well as extant mammals that may represent functional analogues. We find that Palorchestes had the lowest elbow mobility among mammals sampled, even when afforded joint translations in addition to rotational degrees of freedom. This indicates that Palorchestes was limited to crouched forelimb postures, something highly unusual for mammals of this size. Coupled flexion and abduction created a skewed primary axis of movement at the elbow, suggesting an abducted forelimb posture and humeral rotation gait that is not found among marsupials and unlike that seen in any large mammals alive today. This work introduces new quantitative methods and demonstrates the utility of comparative ROM mapping approaches, highlighting that Palorchestes' forelimb function was unlike its contemporaneous relatives and appears to lack clear functional analogues among living mammals. [ABSTRACT FROM AUTHOR]

Background: A major goal of evolutionary developmental biology is to discover general models and mechanisms that create the phenotypes of organisms. However, universal models of such fundamental growth and form are rare, presumably due to the limited number of physical laws and biological processes that influence growth. One such model is the logarithmic spiral, which has been purported to explain the growth of biological structures such as teeth, claws, horns, and beaks. However, the logarithmic spiral only describes the path of the structure through space, and cannot generate these shapes. Results: Here we show a new universal model based on a power law between the radius of the structure and its length, which generates a shape called a 'power cone'. We describe the underlying 'power cascade' model that explains the extreme diversity of tooth shapes in vertebrates, including humans, mammoths, sabre-toothed cats, tyrannosaurs and giant megalodon sharks. This model can be used to predict the age of mammals with ever-growing teeth, including elephants and rodents. We view this as the third general model of tooth development, along with the patterning cascade model for cusp number and spacing, and the inhibitory cascade model that predicts relative tooth size. Beyond the dentition, this new model also describes the growth of claws, horns, antlers and beaks of vertebrates, as well as the fangs and shells of invertebrates, and thorns and prickles of plants. Conclusions: The power cone is generated when the radial power growth rate is unequal to the length power growth rate. The power cascade model operates independently of the logarithmic spiral and is present throughout diverse biological systems. The power cascade provides a mechanistic basis for the generation of these pointed structures across the tree of life. [ABSTRACT FROM AUTHOR]

The teaching of medical pathology has undergone significant change in the last 30–40 years, especially in the context of employing bottled specimens or 'pots' in classroom settings. The reduction in post-mortem based teaching in medical training programs has resulted in less focus being placed on the ability of students to describe the gross anatomical pathology of specimens. Financial considerations involved in employing staff to maintain bottled specimens, space constraints and concerns with health and safety of staff and student laboratories have meant that many institutions have decommissioned their pathology collections. This report details how full-colour surface scanning coupled with CT scanning and 3 D printing allows the digital archiving of gross pathological specimens and the production of reproductions or replicas of preserved human anatomical pathology specimens that obviates many of the above issues. With modern UV curable resin printing technology, it is possible to achieve photographic quality accurate replicas comparable to the original specimens in many aspects except haptic quality. Accurate 3 D reproductions of human pathology specimens offer many advantages over traditional bottled specimens including the capacity to generate multiple copies and their use in any educational setting giving access to a broader range of potential learners and users. [ABSTRACT FROM AUTHOR]

The relative body masses of predators and their prey strongly affect the predators' ecology. An accurate estimate of the mass of an extinct predator is therefore key to revealing its biology and the structure of the ecosystem it inhabited. Until its extinction, the thylacinewas the largest extant carnivorous marsupial, but little data exist regarding its body mass, with an average of 29.5 kg the most commonly used estimate. According to the costs of carnivory model, this estimate predicts that thylacines would have focused on prey subequal to or larger than themselves; however, many studies of their functional morphology suggest a diet of smaller animals. Here, we present new body mass estimates for 93 adult thylacines, including two taxidermy specimens and four complete mounted skeletons, representing 40 known-sex specimens, using three-dimensional volumetric model-informed regressions. We demonstrate that prior estimates substantially overestimated average adult thylacine body mass. We show mixed-sex population mean (16.7 kg), mean male (19.7 kg), and mean female (13.7 kg) body masses well below prior estimates, and below the 21 kg costs of carnivory threshold. Our data show that the thylacine did not violate the costs of carnivory. The thylacine instead occupied the 14.5-21 kg predator/prey range characterized by small-prey predators capable of occasionally switching to relatively large-bodied prey if necessary. [ABSTRACT FROM AUTHOR]

The Palorchestidae are a family of marsupial megafauna occurring across the eastern Australian continent from the late Oligocene through to their extinction in the Late Pleistocene. The group is known for their odd ‘tapir-like’ crania and distinctive clawed forelimbs, but their appendicular anatomy has never been formally described. We provide the first descriptions of the appendicular skeleton and body mass estimates for three palorchestid species, presenting newly-identified, and in some cases associated, material of mid-Miocene Propalorchestes, Plio-Pleistocene Palorchestes parvus and Pleistocene Palorchestes azael alongside detailed comparisons with extant and fossil vombatiform marsupials. We propose postcranial diagnostic characters at the family, genus and species level. Specialisation in the palorchestid appendicular skeleton evidently occurred much later than in the cranium and instead correlates with increasing body size within the lineage. We conclude that palorchestid forelimbs were highly specialised for the manipulation of their environment in the acquisition of browse, and that they may have adopted bipedal postures to feed. Our results indicate palorchestids were bigger than previously thought, with the largest species likely weighing over 1000 kg. Additionally, we show that P. azael exhibits some of the most unusual forelimb morphology of any mammal, with a uniquely fixed humeroulnar joint unlike any of their marsupial kin, living or extinct. [ABSTRACT FROM AUTHOR]

During the Late Miocene, Africa experienced a number of ecological transitions including the spread of C 4 grasslands, the expansion of the Sahara Desert, the Messinian Salinity Crisis and a number of mammalian migrations and expansions, including the origin of the hominin clade. A detailed understanding of the relationship between environmental change and hominin evolution is hampered by the paucity of data available from terrestrial localities, especially in southern Africa. Here, we present a stable isotope and trace element record from a speleothem from the South African cave site of Hoogland. Uranium-lead dating and magnetostratigraphy places the speleothem within the Messinian Age (7.25–5.33 Ma) of the Late Miocene, making it the oldest known cave deposit from the region near the UNESCO Fossil Hominids of South Africa World Heritage Site (locally known as the "Cradle of Humankind"). Low carbon isotope values indicate a predominantly C 3 vegetation in the vicinity of the cave throughout the period of speleothem growth. It is not possible to determine if this represents a C 3 grassland or a C 3 woodland, but it is clear that an equivalent C 3 -rich environment has yet to be found during the Messinian of east Africa. We conclude that the C 4 grass expansion occurred millions of years later in South Africa than it did in eastern Africa, and that this vegetation shift should be considered when comparing African vegetation change with the late Miocene hominin fossil record. • Speleothem from South Africa dated to late Messinian age, using U–Pb methods. • Carbon isotopes indicate a predominantly C 3 vegetation at this time. • First savannah grasslands in southern Africa occur later than in eastern Africa. • Implications for early hominin environments [ABSTRACT FROM AUTHOR]

Abstract: Objectives: Rapid prototyping (RP) technology is becoming more affordable, faster, and is now capable of building models with a high resolution and accuracy. Due to technological limitations, 3D printing in biological anthropology has been mostly limited to museum displays and forensic reconstructions. In this study, we compared the accuracy of different 3D printers to establish whether RP can be used effectively to reproduce anthropological dental collections, potentially replacing access to oftentimes fragile and irreplaceable original material. Methods: We digitized specimens from the Yuendumu collection of Australian Aboriginal dental casts using a high‐resolution white‐light scanning system and reproduced them using four different 3D printing technologies: stereolithography (SLA); fused deposition modeling (FDM); binder‐jetting; and material‐jetting. We compared the deviations between the original 3D surface models with 3D print scans using color maps generated from a 3D metric deviation analysis. Results: The 3D printed models reproduced both the detail and discrete morphology of the scanned dental casts. The results of the metric deviation analysis demonstrate that all 3D print models were accurate, with only a few small areas of high deviations. The material‐jetting and SLA printers were found to perform better than the other two printing machines. Conclusions: The quality of current commercial 3D printers has reached a good level of accuracy and detail reproduction. However, the costs and printing times limit its application to produce large sample numbers for use in most anthropological studies. Nonetheless, RP offers a viable option to preserve numerically constraint fragile skeletal and dental material in paleoanthropological collections. [ABSTRACT FROM AUTHOR]

South Africa contains a wealth of palaeokarst deposits that have yielded hominin fossils and Early Stone Age archaeology. Despite the complex nature of deposition within many of these caves there has been a dearth of detailed geoarchaeological studies undertaken on these sites. Many sites in South Africa have been interpreted using an overly simplistic Member System based on simplified sedimentological attributes, rather than chronostratigrahic units. Many of the defined Members thus identify different, but contemporary geological processes occurring in the caves. This has caused serious confusion in reconstructing the life histories of palaeocaves and the ages of the fossil remains interned within them. It is critical to uncover new sites that have not been extensively altered by decades of data collection and destructive mining techniques employed early in their discovery. Although unmined sites present their own problems with regards to extensive colluvium cover and access to fossil-bearing units, analysing strata that is found in-situ enhances overall confidence of interpretations drawn. A wealth of geoarchaeological and 3D visualisation techniques can now be employed to aid in the understanding of cave life histories, as well as their excavation. In this paper we present the first attempt to integrate and publish data from a range of such methods on South African fossil bearing palaeokarst using the newly discovered Drimolen Makondo deposit as a case study. This includes the use of ground penetrating radar, 3D visualisation through photogrammetry and multi-scale 3D scanning, micromophology and petrography, palaeomagnetism, mineral magnetism, synchrotron radiation, electron spin resonance, uranium-lead dating and biochronology. Our analysis has allowed us to successfully uncover the full extent of this new ∼2.61 Ma fossil bearing palaeokarst deposit and to visualise and interpret its chronostratigraphy. [ABSTRACT FROM AUTHOR]

Studies have suggested that the proportions of the rostrum and mandible (from short and broad to elongate and narrow) in toothed whales (odontocetes) may be associated with the size of the prey they consume, yet quantitative data on relationships between skull shape and diet have been lacking. Here, we quantified variation in skull shape in extant toothed whales using 3D geometric morphometric analysis. We then used Phylogenetic Generalized Least Squares (PGLS) regression to examine the relationships between skull shape and quantitative data on minimum, average and maximum prey size. When examining all odontocetes, there were only weak correlations between skull shape and prey size. However, when suction feeding taxa were excluded, prey size was correlated with the size of the predator (predator size vs. max prey size: R² = 0.45) as well as the shape of the cranium (cranial robustness vs. minimum prey size: R² = 0.19) and mandible (mandible robustness vs. minimum prey size: R² = 0.27). Considering the prey capture method (suction feeding vs. raptorial feeding) is therefore important for elucidating relationships that exist between form and function. These findings suggest that cranial morphology is intimately linked to prey size niche in toothed whales within specific functional contexts. [ABSTRACT FROM AUTHOR]

The striking resemblance of long-snouted aquatic mammals and reptiles has long been considered an example of morphological convergence, yet the true cause of this similarity remains untested. We addressed this deficit through three-dimensional morphometric analysis of the full diversity of crocodilian and toothed whale (Odontoceti) skull shapes. Our focus on biomechanically important aspects of shape allowed us to overcome difficulties involved in comparing mammals and reptiles, which have fundamental differences in the number and position of skull bones. We examined whether diet, habitat and prey size correlated with skull shape using phylogenetically informed statistical procedures. Crocodilians and toothed whales have a similar range of skull shapes, varying from extremely short and broad to extremely elongate. This spectrum of shapes represented more of the total variation in our dataset than between phylogenetic groups. The most elongate species (river dolphins and gharials) are extremely convergent in skull shape, clustering outside of the range of the other taxa. Our results suggest the remarkable convergence between long-snouted river dolphins and gharials is driven by diet rather than physical factors intrinsic to riverine environments. Despite diverging approximately 288 million years ago, crocodilians and odontocetes have evolved a remarkably similar morphological solution to feeding on similar prey. [ABSTRACT FROM AUTHOR]

Palaeomagnetic analysis indicates that Haasgat, a fossil-bearing palaeocave in the Gauteng Province of South Africa, is dominated by reversed magnetic polarity in its oldest, deepest layers and normal polarity in the younger layers. The presence of in-situ Equus specimens suggests an age of less than ~2.3 Ma, while morphological analysis of faunal specimens from the ex-situ assemblage suggests an age greater than 1.8 Ma. Given this faunal age constraint, the older reversed polarity sections most likely date to the beginning of the Matuyama Chron (2.58-1.95 Ma), while the younger normal polarity deposits likely date to the very beginning of the Olduvai Sub-Chron (1.95-1.78 Ma). The occurrence of a magnetic reversal from reversed to normal polarity recorded in the sequence indicates the deposits of the Bridge Section date to ~1.95 Ma. All the in-situ fossil deposits that have been noted are older than the 1.95 Ma reversal, but younger than 2.3 Ma. Haasgat therefore dates to an interesting time period in South African human evolution that saw the last occurrence of two australopith species at ~2.05-2.02 Ma (Sts5 Australopithecus africanus from Sterkfontein Member 4) to ~1.98 Ma (Australopithecus sediba from Malapa) and the first occurrence of early Homo (Sk847), Paranthropus and the Oldowan within Swartkrans Member 1 between ~2.0 Ma and ~1.8 Ma. [ABSTRACT FROM AUTHOR]

Abstract: We report here on evidence of early Homo around 1.0 Ma (millions of years ago) in the central plains of southern Africa. The human material, a first upper molar, was discovered during the systematic excavation of a densely-packed bone bed in the basal part of the sedimentary sequence at the Cornelia-Uitzoek fossil vertebrate locality. We dated this sequence by palaeomagnetism and correlated the bone bed to the Jaramillo subchron, between 1.07 and 0.99 Ma. This makes the specimen the oldest southern African hominine remains outside the dolomitic karst landscapes of northern South Africa. Cornelia-Uitzoek is the type locality of the Cornelian Land Mammal Age. The fauna contains an archaic component, reflecting previous biogeographic links with East Africa, and a derived component, suggesting incipient southern endemism. The bone bed is considered to be the result of the bone collecting behaviour of a large predator, possibly spotted hyaenas. Acheulian artefacts are found in small numbers within the bone bed among the fossil vertebrates, reflecting the penecontemporaneous presence of people in the immediate vicinity of the occurrence. The hominine tooth was recovered from the central, deeper part of the bone bed. In size, it clusters with southern African early Homo and it is also morphologically similar. We propose that the early Homo specimen forms part of an archaic component in the fauna, in parallel with the other archaic faunal elements at Uitzoek. This supports an emergent pattern of archaic survivors in the southern landscape at this time, but also demonstrates the presence of early Homo in the central plains of southern Africa, beyond the dolomitic karst areas. [Copyright &y& Elsevier]

The article presents the discussion on last occurrence of the genus Australopithecus and the first occurrence of Paranthropus and Homo including the combination of uranium-lead dating on flowstones and uranium-series electron .