Using X-ray Microtomography to Discriminate Between Dogs’ and Wolves’ Lower Carnassial Tooth

Dogs and wolves exhibit similar dental features since they belong to the same species. Here we explore a new method to discriminate between wild and domestic forms, based on the analysis of the internal structure of the teeth. We analysed the lower first molar of 21 dogs and 17 wolves. X-ray microtomographic analyses were performed and tooth tissue proportions were assessed by the proportion of the dentine volume. As a result, dog molars show a lower percentage of dentine than those of wolves. This analysis offers promising applications in the study of dog domestication origins

New evaluation of the Castel di Guido \u27hyoid\u27

Castel di Guido is located west of Rome and part of the Aurelian formation (Mariani-Constantini et al., 2001) along with other sites such as Torre in Petra and La Polledrara (Mussi, 2001). These localities are a mixture of surface collections and excavated sites, all associated with Acheulean tools and dated to MIS 9. At Castel di Guido material was collected from the surface and excavations in an erosional channel (Mariani-Constantini et al., 2001; Mussi, 2001). The Middle Pleistocene dates suggest an age of around 400 ka. Direct associations between the human bones and tools do not exist, but based on the size and degree of fossilization the human material is thought to be late Acheulean. The deposits overlie tuffs from the Sabatini volcanic eruptions, dated at 431 ka+/-40 ka - 438 ka +/- 40 ka. so cannot be older than this. Originally six fragmentary bones were recovered from the site (Alciati et al., 2005) but Capasso, Michetti & D\u27Anastasio (2008) found additional material based on their survey of the material for post-mortem modifications

Digital reconstruction of the Ceprano calvarium (Italy), and implications for its interpretation

The Ceprano calvarium was discovered in fragments on March 1994 near the town of Ceprano in southern Latium (Italy), embedded in Middle Pleistocene layers. After reconstruction, its morphological features suggests that the specimen belongs to an archaic variant of H. heidelbergensis, representing a proxy for the last common ancestor of the diverging clades that respectively led to H. neanderthalensis and H. sapiens. Unfortunately, the calvarium was taphonomically damaged. The postero-lateral vault, in particular, appears deformed and this postmortem damage may have infuenced previous interpretations. Specifcally, there is a depression on the fragmented left parietal, while the right cranial wall is warped and angulated. This deformation afected the shape of the occipital squama, producing an inclination of the transverse occipital torus. In this paper, after X-ray microtomography (μCT) of both the calvarium and several additional fragments, we analyze consistency and pattern of the taphonomic deformation that afected the specimen, before the computer-assisted retrodeformation has been performed; this has also provided the opportunity to reappraise early attempts at restoration. As a result, we ofer a revised interpretation for the Ceprano calvarium’s original shape, now free from the previous uncertainties, along with insight for its complex depositional and taphonomic history

Exploring Hominin and Non-hominin Primate Dental Fossil Remains with Neutron Microtomography

Fossil dental remains are an archive of unique information for paleobiological studies. Computed microtomography based on X-ray microfocus sources (X-μCT) and Synchrotron Radiation (SR-μCT) allow subtle quantification at the micron and sub-micron scale of the meso- and microstructural signature imprinted in the mineralized tissues, such as enamel and dentine, through high-resolution virtual histology . Nonetheless, depending on the degree of alterations undergone during fossilization, X-ray analyses of tooth tissues do not always provide distinct imaging contrasts, thus preventing the extraction of essential morphological and anatomical details. We illustrate here by three examples the successful application of neutron microtomography (n-μCT) in cases where X-rays have previously failed to deliver contrasts between dental tissues of fossilized specimen

Becoming adults: Exploring the late ontogeny of the human talus

Introduction: The talus plays an important role in receiving and dissipating the forces and linking the leg and the foot. As such, it is of paramount importance to analyze how its morphology, internal and external, changes during late ontogeny and through adolescence. Method: To explore both the external shape and the internal architecture of the talus, Geometric Morphometrics and trabecular analysis have been applied to a sample of 35 tali from modern human juveniles aged between 5 and 15 years old (Middle Neolithic (4800-4500 BCE) to mid-20th century). Results: Results show that, as the overall size of the talus increases, the shape and orientation of talar facets also change. The youngest individuals exhibit a functional talus that is still characterized by a relatively immature shape (e.g., subtly expressed margins of articular surfaces) with articular facets only minimally rotated towards an adult configuration. In adolescents, talar shape has achieved adult form after the age of 11, with all the articular facets and posterior processes well-developed. Considering internal morphology, trabecular bone varies between age classes. While Bone Volume Fraction shifts during the age 5-15 range, Degree of Anisotropy is relatively more stable over the developmental period examined in the study since it exhibits smaller variations between age classes. Discussion: This study examined the late ontogeny of the human talus by considering both internal and external morphology. Results suggest that, although the locomotion has already assumed an adult-like pattern, the exploration of late talar growth may help understand how the talus adapts to changes in locomotor activity and how it responds to the increase in weight. Present results can be used to a better understanding of talar plasticity, improving interpretations of adult human talar form

Human talar ontogeny: Insights from morphological and trabecular changes during postnatal growth

The study of the development of human bipedalism can provide a unique perspective on the evolution of morphology and behavior across species. To generate new knowledge of these mechanisms, we analyze changes in both internal and external morphology of the growing human talus in a sample of modern human juveniles using an innovative approach. The sample consists of high‐resolution microCT scans of 70 modern juvenile tali, aged between 8 postnatal weeks and 10 years old, from a broad chronological range from Middle/Late Neolithic, that is, between 4800 and 4500 BCE, to the 20th century. We applied geometric morphometric and whole‐bone trabecular analysis (bone volume fraction, degree of anisotropy, trabecular number, thickness, and spacing) to all specimens to identify changes in the external and internal morphology during growth. Morphometric maps were also generated. During the first year of life, the talus has an immature and globular shape, with a dense, compact, and rather isotropic trabecular architecture, with numerous trabeculae packed closely together. This pattern changes while children acquire a more mature gait, and the talus tends to have a lower bone volume fraction, a higher anisotropy, and a more mature shape. The changes in talar internal and external morphologies reflect the different loading patterns experienced during growth, gradually shifting from an “unspecialized” morphology to a more complex one, following the development of bipedal gait. Our research shows that talar plasticity, even though genetically driven, may show mechanical influences and contribute to tracking the main locomotor milestones

Early life of Neanderthals

The early onset of weaning in modern humans has been linked to the high nutritional demand of brain development that is intimately connected with infant physiology and growth rate. In Neanderthals, ontogenetic patterns in early life are still debated, with some studies suggesting an accelerated development and others indicating only subtle differences to modern humans. Here we report the onset of weaning and rates of enamel growth using an unprecedented sample set of three late (~70-50 ka) Neanderthals and one Upper Paleolithic modern human from Northeastern-Italy via spatially-resolved chemical/isotopic analyses and histomorphometry of deciduous teeth. Our results reveal that the modern human nursing strategy, with onset of weaning at 5-6 months, was present among these Neanderthals. This evidence, combined with dental development akin to modern humans, highlights their similar metabolic constraints during early life and excludes late weaning as a factor contributing to Neanderthals' demise

On the distribution of bomb carbon-14 in the Southern Ocean

In an earlier WOCE newsletter (Ribbe & Tomczak, 1995) we reported on the development of an off-line radiocarbon validated tracer model for the Southern Ocean based on the Fine Resolution Antarctic Model (FRAM). During the initial stages of the project computational experiment were carried out with the model for an idealised oceanic tracer. We intended to verify the physical mechanisms that operate in the model and are responsible for removing atmospheric tracer and surface water. The results of these experiments have recently been reported in a series of papers (Ribbe & Tomczak, 1996a, 1996b, 1996c) and some very early results were published in this newsletter previously

Radioactivity: a very short introduction

Radioactivity: A Very Short Introduction explains radioactivity and discusses its fundamental role in nature. Radioactivity remains misunderstood and feared perhaps because nuclear radiation cannot be detected by human senses, and can undoubtedly do great harm if appropriate precautions are not taken. Radioactivity in the stars and in the Earth and its wide range of applications in biomedicine, science, industry, agriculture are described, as well as the mechanisms of nuclear fission and fusion, and the harnessing of nuclear power. The issues surrounding safety and security and the increasing concerns about nuclear terrorism are also considered

La Scimmia vestita, dalle tribù di primati all’intelligenza artificiale

Per capire il nostro rapporto con le tecnologie digitali dobbiamo tornare indietro al passato in cui le immagini e i simboli ampliarono la nostra mente e gli strumenti svilupparono il nostro corpo. Claudio Tuniz è uno scienziato del Centro Internazionale di Fisica Teorica Abdus Salam di Trieste, del Centro Fermi di Roma e del Centro per le Scienze Archeologiche in Australia. Promuove l’uso delle nuove metodologie fisiche negli studi sulle origini umane. Su questo tema ha pubblicato anche libri divulgativi come “La scienza delle nostre origini” (con G. Manzi e D. Caramelli, Laterza, 2013) e “I lettori di ossa” (con R. Gillespie e C. Jones, Springer, 2010). Patrizia Tiberi Vipraio è stata professoressa ordinaria di Politica Economica e docente di Economia Internazionale presso l'Università di Udine e Sidney. Fra i suoi lavori accademici ha pubblicato anche “Dal Mercantilismo alla globalizzazione” (Il Mulino, Bologna, 1999). Congiuntamente hanno pubblicato “La scimmia vestita. Dalle tribù di primati all'intelligenza artificiale”, Carocci, 2018 e “Homo sapiens”, Carocci, 2015