One hominin taxon or two at Malapa Cave? Implications for the origins of Homo

A report on the skeletons of two individuals from the Malapa cave site in South Africa attributes them both to a new hominin species, Australopithecus sediba. However, our analysis of the specimens’ mandibles indicates that  Australopithecus sediba is not a ‘Homo-like australopith’, a transitional species between Australopithecus africanus and Homo. According to our results, the specimens represent two separate genera:  Australopithecus and Homo. These genera are known to have jointly occupied sites, as seen in several early South African caves, so one cannot rule out the possibility that Malapa also contains remains of the two taxa. Our results lead us to additionally conclude that all the Australopithecus species on which the relevant mandibular anatomy is preserved (not only the ‘robust’ australopiths but also the ‘gracile’ – more generalised – ones) are too specialised to constitute an evolutionary ancestor of Homo sapiens. Furthermore, given that the Malapa site contains representatives of two hominin branches, one of which appears to be Homo, we must seek evidence of our origins much earlier than the date assigned to Malapa, approximately 2 million years before present. Support for this claim can be found in Ethiopian fossils attributed to the genus Homo and dated at 2.4 and 2.8 million years before present.Significance: The proposed hominin species Australopithecus sediba, from the Malapa Cave in South Africa, seems to actually consist of two species, each of which represents a different hominin genus: Homo and  Australopithecus. If, indeed, this is the case, Homo must have originated prior to the Malapa remains, contrary to the scenario suggested in the original report on Au. sediba

The first Neanderthal remains from an open-air Middle Palaeolithic site in the Levant

The late Middle Palaeolithic (MP) settlement patterns in the Levant included the repeated use of caves and open landscape sites. The fossil record shows that two types of hominins occupied the region during this period - Neandertals and Homo sapiens. Until recently, diagnostic fossil remains were found only at cave sites. Because the two populations in this region left similar material cultural remains, it was impossible to attribute any open-air site to either species. In this study, we present newly discovered fossil remains from intact archaeological layers of the open-air site 'Ein Qashish, in northern Israel. The hominin remains represent three individuals: EQH1, a nondiagnostic skull fragment; EQH2, an upper right third molar (RM3); and EQH3, lower limb bones of a young Neandertal male. EQH2 and EQH3 constitute the first diagnostic anatomical remains of Neandertals at an open-air site in the Levant. The optically stimulated luminescence ages suggest that Neandertals repeatedly visited 'Ein Qashish between 70 and 60 ka. The discovery of Neandertals at open-air sites during the late MP reinforces the view that Neandertals were a resilient population in the Levant shortly before Upper Palaeolithic Homo sapiens populated the region

Effect of remote ischaemic conditioning on clinical outcomes in patients with acute myocardial infarction (CONDI-2/ERIC-PPCI): a single-blind randomised controlled trial.

BACKGROUND: Remote ischaemic conditioning with transient ischaemia and reperfusion applied to the arm has been shown to reduce myocardial infarct size in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). We investigated whether remote ischaemic conditioning could reduce the incidence of cardiac death and hospitalisation for heart failure at 12 months. METHODS: We did an international investigator-initiated, prospective, single-blind, randomised controlled trial (CONDI-2/ERIC-PPCI) at 33 centres across the UK, Denmark, Spain, and Serbia. Patients (age >18 years) with suspected STEMI and who were eligible for PPCI were randomly allocated (1:1, stratified by centre with a permuted block method) to receive standard treatment (including a sham simulated remote ischaemic conditioning intervention at UK sites only) or remote ischaemic conditioning treatment (intermittent ischaemia and reperfusion applied to the arm through four cycles of 5-min inflation and 5-min deflation of an automated cuff device) before PPCI. Investigators responsible for data collection and outcome assessment were masked to treatment allocation. The primary combined endpoint was cardiac death or hospitalisation for heart failure at 12 months in the intention-to-treat population. This trial is registered with ClinicalTrials.gov (NCT02342522) and is completed. FINDINGS: Between Nov 6, 2013, and March 31, 2018, 5401 patients were randomly allocated to either the control group (n=2701) or the remote ischaemic conditioning group (n=2700). After exclusion of patients upon hospital arrival or loss to follow-up, 2569 patients in the control group and 2546 in the intervention group were included in the intention-to-treat analysis. At 12 months post-PPCI, the Kaplan-Meier-estimated frequencies of cardiac death or hospitalisation for heart failure (the primary endpoint) were 220 (8·6%) patients in the control group and 239 (9·4%) in the remote ischaemic conditioning group (hazard ratio 1·10 [95% CI 0·91-1·32], p=0·32 for intervention versus control). No important unexpected adverse events or side effects of remote ischaemic conditioning were observed. INTERPRETATION: Remote ischaemic conditioning does not improve clinical outcomes (cardiac death or hospitalisation for heart failure) at 12 months in patients with STEMI undergoing PPCI. FUNDING: British Heart Foundation, University College London Hospitals/University College London Biomedical Research Centre, Danish Innovation Foundation, Novo Nordisk Foundation, TrygFonden

Spino-pelvic alignment: An evolutionary perspective

Presentación en: 4rd Annual Meeting of the European Society for the study of Human Evolution (Florence, Italy ; 18-20 September 2014)During human evolution the spinal curvature as well as pelvic and sacral orientation have changed dramatically, from a very small pelvic incidence and spinal curvatures in non human hominoids to large curvatures in modern humans. This change was accompanied by a dramatic shift of the line of gravity and C7 plumb line. In this work we will describe the spino-pelvic adjustments to upright posture and bipedality of four major hominin groups; Australopithecines, H. erectus, Neandertals and H. sapiens.Peer reviewe

The Association between Imaging Parameters of the Paraspinal Muscles, Spinal Degeneration, and Low Back Pain

This narrative review investigated imaging parameters of the paraspinal muscles and their association with spinal degenerative features and low back pain (LBP) found in the literature. Three principal signs of muscle degeneration were detected on imaging: decreased muscle size, decreased radiographic density, and increased fat deposits. Men have a higher density of paraspinal muscles than women, younger individuals have a higher density than older ones, and lean individuals have a higher density than those with an increased body mass index. Fatty infiltration appears to be a late stage of muscular degeneration and can be measured noninvasively by an MRI scan. Fatty infiltration in the lumbar multifidus is common in adults and is strongly associated with LBP, especially in women, independent of body composition. Fatty infiltration develops in areas where most degenerative changes are found. MR spectroscopy studies have corroborated that the lumbar multifidus in LBP subjects has a significantly higher fat content than asymptomatic controls. There is a strong need for establishing uniform methods of evaluating normal parameters and degenerative changes of the paraspinal muscles. Additional imaging studies are needed to improve the understanding of the association and causal relationships between LBP, spinal degeneration, and changes in the paraspinal muscles

One hominin taxon or two at Malapa Cave? Implications for the origins of Homo

A report on the skeletons of two individuals from the Malapa cave site in South Africa attributes them both to a new hominin species, Australopithecus sediba. However, our analysis of the specimens’ mandibles indicates that Australopithecus sediba is not a ‘Homo-like australopith’, a transitional species between Australopithecus africanus and Homo. According to our results, the specimens represent two separate genera: Australopithecus and Homo. These genera are known to have jointly occupied sites, as seen in several early South African caves, so one cannot rule out the possibility that Malapa also contains remains of the two taxa. Our results lead us to additionally conclude that all the Australopithecus species on which the relevant mandibular anatomy is preserved (not only the ‘robust’ australopiths but also the ‘gracile’ – more generalised – ones) are too specialised to constitute an evolutionary ancestor of Homo sapiens. Furthermore, given that the Malapa site contains representatives of two hominin branches, one of which appears to be Homo, we must seek evidence of our origins much earlier than the date assigned to Malapa, approximately 2 million years before present. Support for this claim can be found in Ethiopian fossils attributed to the genus Homo and dated at 2.4 and 2.8 million years before present.Significance: The proposed hominin species Australopithecus sediba, from the Malapa Cave in South Africa, seems to actually consist of two species, each of which represents a different hominin genus: Homo and Australopithecus. If, indeed, this is the case, Homo must have originated prior to the Malapa remains, contrary to the scenario suggested in the original report on Au. sediba

The Neandertal vertebral column 1: The cervical spine

This paper provides a metric analysis of the Neandertal cervical spine in relation to modern human variation. All seven cervical vertebrae have been analysed. Metric data from eight Neandertal individuals are compared with a large sample of modern humans. The significance of morphometric differences is tested using both z-scores and two-tailed Wilcoxon signed rank tests. The results identify significant metric and morphological differences between Neandertals and modern humans in all seven cervical vertebrae. Neandertal vertebrae are mediolaterally wider and dorsoventrally longer than modern humans, due in part to longer and more horizontally oriented spinous processes. This suggests that Neandertal cervical morphology was more stable in both mid-sagittal and coronal planes. It is hypothesized that the differences in cranial size and shape in the Neandertal and modern human lineages from their Middle Pleistocene ancestors could account for some of the differences in the neck anatomy between these species

Evolution of spinopelvic alignment in hominins

Spinopelvic alignment refers to the interaction between pelvic orientation, spinal curvatures, and the line of gravity. In a healthy modern human, this alignment is characterized by reciprocal curves/orientation of the sacrum, lumbar lordosis, thoracic kyphosis, and cervical lordosis. In an economic sagittal posture, these curvatures keep the line of gravity close to the center of the acetabulum. The purpose of this study is to explore the spinopelvic alignment in extinct hominins. We examined spinopelvic alignment of a single representative from each of the following hominin groups: Australopithecus, Homo erectus (H. erectus), H. neanderthalensis, and early H. sapiens. Pelvic incidence, lumbar lordosis, thoracic kyphosis, and cervical lordosis for each representative was estimated and compared with that of modern humans. Three basic spinopelvic alignments were found: (1) the sinusoidal alignment with moderate to high spinal curvatures and pelvic incidence found in H. erectus and H. sapiens; (2) the straight alignment with small spinal curvatures and small pelvic incidence found in Neandertal lineage hominins; (3) the compound alignment found in Australopithecus, with moderate pelvic incidence and lumbar lordosis, and nearly straight cervical spine. Our results indicate that balanced upright posture can be achieved in different alignments. Each hominin group solved the requirements of erect posture in a slightly different way. Moreover, we propose the term “cranio-spino-pelvic balance” to substitute “spino-pelvic balance.” From an evolutionary perspective, not only changes in the pelvis have conditioned the evolution of the spinal curvatures but also changes in the equilibrium of the head likely also affected this balance. Anat Rec, 300:900–911, 2017. © 2017 Wiley Periodicals, Inc.Grant sponsor: Ministerio de Economıa y Competitividad; Grant numbers: CGL2012-37279, CGL2012-38434-C03-01, CGL2015-63648-P, and CGL-2015-65387-C3-2-P MINECO/FEDER.Peer Reviewe

Thorax kinematics and the reconstruction of body models in hominin evolution

Póster en: 4rd Annual Meeting of the European Society for the study of Human Evolution (Florence, Italy ; 18-20 September 2014)Peer reviewe