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1.
Am J Hosp Palliat Care ; 41(5): 492-500, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37288486

RESUMO

BACKGROUND: Residents often feel unprepared to care for dying patients and may benefit from more training. Little is known about factors in the clinical setting that promote resident learning about end of life (EOL) care. OBJECTIVES: This qualitative study aimed to characterize the experiences of residents caring for dying patients and elucidate the impact of emotional, cultural, and logistical factors on learning. METHODS: 6 US internal medicine and 8 pediatric residents who had cared for at least 1 dying patient completed a semi-structured one-on-one interview between 2019 and 2020. Residents described an experience caring for a dying patient including their confidence in clinical skills, emotional experience, role within the interdisciplinary team, and perspective on how to improve their education. Interviews were transcribed verbatim and investigators conducted content analysis to generate themes. RESULTS: 3 themes (with subthemes) emerged: (1) experiencing strong emotion or tension (loss of patient personhood, emerging professional identity, emotional dissonance); (2) processing the experience (innate resilience, team support); and (3) recognition of a new perspective or skill (bearing witness, meaning making, recognizing biases, emotional work of doctoring). CONCLUSIONS: Our data suggests a model for the process by which residents learn affective skills critical to EOL care: residents (1) notice strong emotion, (2) reflect on the meaning of the emotion, and (3) crystallize this reflection into a new perspective or skill. Educators can use this model to develop educational methods that emphasize normalization of physician emotions and space for processing and professional identity formation.


Assuntos
Internato e Residência , Médicos , Assistência Terminal , Humanos , Criança , Assistência Terminal/psicologia , Médicos/psicologia , Emoções , Aprendizagem , Currículo
2.
EClinicalMedicine ; 65: 102291, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38021372

RESUMO

Background: Meta-analyses indicate superiority of antipsychotic maintenance treatment over discontinuation within up to 24 months after treatment initiation for patients with schizophrenia-spectrum disorders. In terms of functional recovery, long-term trials show improved functioning after discontinuation, suggesting a time-dependent effect of antipsychotic maintenance. However, these trials were not included in previous meta-analyses. We therefore investigated whether the effect of antipsychotic maintenance treatment vs. discontinuation on social functioning and quality of life varies by trial length. Methods: The study was preregistered with PROSPERO (CRD42021248933). PubMed, PsycINFO, Web of Science, Embase and trial registers were systematically searched on 8th November 2021 and updated on 25th June, 2023 and 10th August, 2023 for studies that compared antipsychotic maintenance to discontinuation and reported data on social functioning or subjective quality of life in patients with schizophrenia-spectrum disorders. Risk of bias was assessed with the RoB 2, the ROBINS-I and the RoB-ME tools. Quality of evidence was rated using the Grading of Recommendations Assessment, Development, and Evaluation approach. Findings: We included k = 35 studies (N = 5924) with follow-ups between one month and 15 years. Overall, maintenance and discontinuation did not differ on social functioning (k = 32; n = 5330; SMD = 0.204; p = 0.65; 95% CI [-0.69, 1.10]) or quality of life (k = 10; n = 943; SMD = -0.004; p = 0.97; 95% CI [-0.22, 0.21]), whilst subgroup analyses of middle- (2-5 years; k = 7; n = 1032; SMD = 0.68; 95% CI [0.06, 1.28]) and long-term follow-ups (>5 years; k = 2; n = 356; SMD = 1.04; 95% CI [0.82, 1.27]) significantly favoured discontinuation. However, the quality of evidence was rated as very low. Interpretation: Although our findings suggest a time-dependent decrease in the effect of maintenance treatment on social functioning, interpretation of these findings is limited by the serious risk of bias in middle- and long-term trials. Therefore, any conclusions regarding the long-term benefits of antipsychotic treatment or discontinuation for functional recovery are premature and more high-quality trials tailored to comparing state of the art maintenance treatment vs. discontinuation are needed. Funding: None.

3.
BMC Gastroenterol ; 23(1): 12, 2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36635643

RESUMO

BACKGROUND: Primary sclerosing cholangitis (PSC) is a rare cholestatic liver disease with a largely unpredictable course. Due to limited treatment options, individuals may for many years suffer from distressing symptoms and the emotional burden of an uncertain future. The need to shift from cure to care of PSC has spurred an interest into patients' health-related quality of life. Qualitative research in this context remains scarce. Hence, this study aimed to enrich the clinical understanding about the lived experience of PSC through a qualitative approach. METHODS: A total of 20 patients with PSC were recruited at a specialist centre for autoimmune liver disease in Germany and engaged in semi-structured telephone-based interviews between March and June 2022. Verbatim transcripts were interpreted using inductive thematic analysis. RESULTS: An overarching concept of 'a wave-like experience' was formulated to illustrate the dual and shifting nature of living with PSC. Reflecting upon this central idea, three major themes were generated to address important aspects of participants' illness experiences: 'Invisible presence' focused on perceptions of suffering from a seemingly hidden illness that periodically reveals itself through specific trigger events. 'Embracing the threat' captured the psycho-emotional response shift to this chronic disease from a predominantly negative to a coping-oriented pattern with regular setbacks. 'Between control and constraints' uncovered restrictions that PSC enforces onto patients' lives and their desire for controllability. CONCLUSIONS: The present study provides an in-depth look at the fluctuating tensions arising from a life with PSC. Insights on perceived invisibility, disease-related triggers of emotional distress and the complexity behind self-management highlight opportunities for enhanced clinical support of this patient group.


Assuntos
Colangite Esclerosante , Qualidade de Vida , Humanos , Qualidade de Vida/psicologia , Pesquisa Qualitativa , Adaptação Psicológica , Doença Crônica
4.
Cells ; 11(22)2022 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-36428956

RESUMO

Reduction of insulin/insulin-like growth factor 1 (IGF1) signaling (IIS) promotes longevity across species. In the nematode Caenorhabditis elegans, ablation of germline stem cells (GSCs) and activity changes of the conserved signaling mediators unc-43/CaMKII (calcium/calmodulin-dependent kinase type II) and egl-8/PLCß (phospholipase Cß) also increase lifespan. Like IIS, these pathways depend on the conserved transcription factor daf-16/FOXO for lifespan extension, but how they functionally interact is unknown. Here, we show that altered unc-43/egl-8 activity further increases the lifespan of long-lived GSC-deficient worms, but not of worms that are long-lived due to a strong reduction-of-function mutation in the insulin/IGF1-like receptor daf-2. Additionally, we provide evidence for unc-43 and, to a lesser extent, egl-8 modulating the expression of certain collagen genes, which were reported to be dispensable for longevity of these particular daf-2 mutant worms, but not for other forms of longevity. Together, these results provide new insights into the conditions and potential mechanisms by which CaMKII- and PLCß-signals modulate C. elegans lifespan.


Assuntos
Proteínas de Caenorhabditis elegans , Insulinas , Animais , Caenorhabditis elegans/metabolismo , Longevidade/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Fosfolipase C beta/genética , Fosfolipase C beta/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Células Germinativas/metabolismo , Mutação/genética , Insulinas/genética , Insulinas/metabolismo
5.
Sci Adv ; 8(42): eabp9767, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36269821

RESUMO

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.


Assuntos
Fósseis , Hominidae , Animais , Humanos , Crânio/anatomia & histologia , Encéfalo , Clima
6.
BMJ Open ; 12(12): e061419, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36600365

RESUMO

INTRODUCTION: Fatigue is a common symptom and the major 'unmet need' in the management of patients with primary biliary cholangitis (PBC). To date, only few prospective studies have addressed the development of PBC-associated fatigue over time. At the same time, few biological and psychosocial risk factors and mechanisms have been identified that could explain the development and maintenance of fatigue in PBC. It is the overall aim of this study to identify factors that determine the course and severity of fatigue in PBC, and to target these factors within deliverable interventions in order to improve patients' quality of life. METHODS AND ANALYSIS: To identify biological and psychosocial risk factors for severe fatigue, a prospective 12-month cohort study with one baseline and two follow-up measurements will be conducted. In a cross-sectional part, we will simultaneously examine clinically relevant biomedical and psychosocial factors and systematically assess and compare associations and interactions between these factors and fatigue in n=240 patients with PBC (a patient group severely affected by fatigue) and n=240 patients with primary sclerosing cholangitis, a control cholestatic liver disease group much less affected by fatigue. In a prospective part, we will longitudinally monitor these variables and assess their predictive value at 12-month follow-up. Within an embedded mixed-methods design, we will conduct an experimental study and qualitative interviews in patients with newly diagnosed PBC. ETHICS AND DISSEMINATION: The study was approved by the Ethics Committee of the Hamburg Medical Association (2020-10196-BO-ff). The study will shed light onto the mechanisms underlying the evolvement and maintenance of fatigue in patients with PBC and enable the development of evidence-based intervention strategies. Findings will be disseminated through peer-reviewed publications, scientific conferences and the involvement of relevant stakeholders, patients and the lay public. TRIAL REGISTRATION NUMBER: ISRCTN14379650.


Assuntos
Cirrose Hepática Biliar , Humanos , Cirrose Hepática Biliar/complicações , Estudos Prospectivos , Estudos de Coortes , Qualidade de Vida , Estudos Transversais , Fadiga/complicações
7.
Schizophr Bull ; 48(2): 307-324, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34635918

RESUMO

Based on findings from cognitive science, it has been theorized that the reductions in motivation and goal-directed behavior in people with psychosis could stem from impaired episodic memory. In the current meta-analysis, we investigated this putative functional link between episodic memory deficits and negative symptoms. We hypothesized that episodic memory deficits in psychosis would be related to negative symptoms in general but would be more strongly related to amotivation than to reduced expressivity. We included 103 eligible studies (13,622 participants) in the analyses. Results revealed significant, moderate negative associations of episodic memory with negative symptoms in general (k = 103; r = -.23; z = -13.40; P ≤ .001; 95% CI [-.26; -.20]), with amotivation (k = 16; r = -.18; z = -6.6; P ≤ .001; 95% CI [-.23; -.13]) and with reduced expressivity (k = 15; r = -.18; z = -3.30; P ≤.001; 95% CI[-.29; -.07]). These associations were not moderated by sociodemographic characteristics, positive symptoms, depression, antipsychotic medication or type of negative symptom scale. Although these findings provide sound evidence for the association between episodic memory deficits and amotivation, the rather small magnitude and the unspecific pattern of this relationship also indicate that episodic memory deficits are unlikely to be the only factor relevant to amotivation. This implicates that future research should investigate episodic memory in conjunction with other factors that could account for the association of episodic memory deficits and amotivation in psychosis.


Assuntos
Memória Episódica , Motivação , Transtornos Psicóticos/complicações , Adulto , Antipsicóticos/farmacologia , Antipsicóticos/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Psicóticos/psicologia , Esquizofrenia/tratamento farmacológico
8.
J Hum Evol ; 159: 103049, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34455262

RESUMO

Ancient DNA analyses have shown that interbreeding between hominin taxa occurred multiple times. Although admixture is often reflected in skeletal phenotype, the relationship between the two remains poorly understood, hampering interpretation of the hominin fossil record. Direct study of this relationship is often impossible due to the paucity of hominin fossils and difficulties retrieving ancient genetic material. Here, we use a sample of known ancestry hybrids between two closely related nonhuman primate taxa (Indian and Chinese Macaca mulatta) to investigate the effect of admixture on skeletal morphology. We focus on pelvic shape, which has potential fitness implications in hybrids, as mismatches between maternal pelvic and fetal cranial morphology are often fatal to mother and offspring. As the pelvis is also one of the skeletal regions that differs most between Homo sapiens and Neanderthals, investigating the pelvic consequences of interbreeding could be informative regarding the viability of their hybrids. We find that the effect of admixture in M. mulatta is small and proportional to the relatively small morphological difference between the parent taxa. Sexual dimorphism appears to be the main determinant of pelvic shape in M. mulatta. The lack of difference in pelvic shape between Chinese and Indian M. mulatta is in contrast to that between Neanderthals and H. sapiens, despite a similar split time (in generations) between the hybridizing pairs. Greater phenotypic divergence between hominins may relate to adaptations to disparate environments but may also highlight how the unique degree of cultural buffering in hominins allowed for greater neutral divergence. In contrast to some previous work identifying extreme morphologies in first- and second-generation hybrids, here the relationship between pelvic shape and admixture is linear. This linearity may be because most sampled animals have a multigenerational admixture history or because of relatively high constraints on the pelvis compared with other skeletal regions.


Assuntos
Hominidae , Homem de Neandertal , Animais , Evolução Biológica , Fósseis , Macaca , Pelve
9.
Evol Anthropol ; 30(3): 199-220, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33951239

RESUMO

Questions surrounding the timing, extent, and evolutionary consequences of archaic admixture into human populations have a long history in evolutionary anthropology. More recently, advances in human genetics, particularly in the field of ancient DNA, have shed new light on the question of whether or not Homo sapiens interbred with other hominin groups. By the late 1990s, published genetic work had largely concluded that archaic groups made no lasting genetic contribution to modern humans; less than a decade later, this conclusion was reversed following the successful DNA sequencing of an ancient Neanderthal. This reversal of consensus is noteworthy, but the reasoning behind it is not widely understood across all academic communities. There remains a communication gap between population geneticists and paleoanthropologists. In this review, we endeavor to bridge this gap by outlining how technological advancements, new statistical methods, and notable controversies ultimately led to the current consensus.


Assuntos
Evolução Biológica , DNA Antigo/análise , Introgressão Genética/genética , Homem de Neandertal/genética , Animais , Antropologia Física , DNA Mitocondrial/genética , Hominidae/classificação , Hominidae/genética , Humanos , Homem de Neandertal/classificação
10.
Anat Rec (Hoboken) ; 304(12): 2645-2660, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33586866

RESUMO

Maternal malnutrition during gestation and lactation is known to have adverse effects on offspring. We evaluate the impact of maternal diet on offspring bony labyrinth morphology. The bony labyrinth develops early and is thought to be stable to protect vital sensory organs within. For these reasons, bony labyrinth morphology has been used extensively to assess locomotion, hearing function, and phylogeny in primates and numerous other taxa. While variation related to these parameters has been documented, there is still a component of intraspecific variation that is unexplained. Although the labyrinthine developmental window is small, it may provide the opportunity for developmental instability to produce corresponding shape differences, as measured by fluctuating asymmetry (FA). We hypothesized that (a) offspring with poor maternal diet would exhibit increased FA, but (b) no unilateral shape difference. To test these hypotheses, we used two groups of rats (Rattus norvegicus; Crl:WI[Han] strain), one control group and one group exposed to a isocaloric, protein-restricted maternal diet during gestation and suckling. Individuals were sampled at weaning, sexual maturity, and old age. A Procrustes analysis of variance identified statistically significant FA in all diet-age subgroups. No differences in level of FA were identified among the subgroups, rejecting our first hypothesis. A principal components analysis identified no unilateral shape differences, supporting our second hypothesis. These results indicate that bony labyrinth morphology is remarkably stable and likely protected from a poor maternal diet during development. In light of this result, other factors must be explored to explain intraspecific variation in labyrinthine shape.


Assuntos
Orelha Interna , Desnutrição , Animais , Feminino , Troca Materno-Fetal , Gravidez , Ratos
12.
Sci Adv ; 6(24): eaaz0183, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32582847

RESUMO

Africa hosts the greatest human genetic diversity globally, but legacies of ancient population interactions and dispersals across the continent remain understudied. Here, we report genome-wide data from 20 ancient sub-Saharan African individuals, including the first reported ancient DNA from the DRC, Uganda, and Botswana. These data demonstrate the contraction of diverse, once contiguous hunter-gatherer populations, and suggest the resistance to interaction with incoming pastoralists of delayed-return foragers in aquatic environments. We refine models for the spread of food producers into eastern and southern Africa, demonstrating more complex trajectories of admixture than previously suggested. In Botswana, we show that Bantu ancestry post-dates admixture between pastoralists and foragers, suggesting an earlier spread of pastoralism than farming to southern Africa. Our findings demonstrate how processes of migration and admixture have markedly reshaped the genetic map of sub-Saharan Africa in the past few millennia and highlight the utility of combined archaeological and archaeogenetic approaches.

13.
J Pain Symptom Manage ; 60(2): e1-e6, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32437944

RESUMO

Effective prognostication for a novel disease presents significant challenges, especially given the stress induced during a pandemic. We developed a point-of-care tool to summarize outcome data for critically ill patients with COVID-19 and help guide clinicians through a thoughtful prognostication process. Two authors reviewed studies of outcomes of patients with critical illness due to COVID-19 and created a visual infographic tool based on available data. Survival data were supplemented by descriptions of best- and worst-case clinical scenarios. The tool also included prompts for clinician reflection designed to enhance awareness of cognitive biases that may affect prognostic accuracy. This online, open-source COVID-19 Prognostication Tool has been made available to all clinicians at our institution and is updated weekly to reflect evolving data. Our COVID-19 Prognostication Tool may provide a useful approach to promoting consistent and high-quality prognostic communication across a health care system.


Assuntos
Infecções por Coronavirus/diagnóstico , Diagnóstico por Computador , Comunicação em Saúde , Pneumonia Viral/diagnóstico , Idoso , COVID-19 , Infecções por Coronavirus/terapia , Cuidados Críticos , Estado Terminal , Visualização de Dados , Diagnóstico por Computador/métodos , Comunicação em Saúde/métodos , Pessoal de Saúde/psicologia , Humanos , Internet , Pessoa de Meia-Idade , Cuidados Paliativos/métodos , Pandemias , Pneumonia Viral/terapia , Sistemas Automatizados de Assistência Junto ao Leito , Preconceito , Prognóstico
14.
Proc Natl Acad Sci U S A ; 117(15): 8416-8423, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32229560

RESUMO

Bipedalism is a defining trait of the hominin lineage, associated with a transition from a more arboreal to a more terrestrial environment. While there is debate about when modern human-like bipedalism first appeared in hominins, all known South African hominins show morphological adaptations to bipedalism, suggesting that this was their predominant mode of locomotion. Here we present evidence that hominins preserved in the Sterkfontein Caves practiced two different locomotor repertoires. The trabecular structure of a proximal femur (StW 522) attributed to Australopithecus africanus exhibits a modern human-like bipedal locomotor pattern, while that of a geologically younger specimen (StW 311) attributed to either Homo sp. or Paranthropus robustus exhibits a pattern more similar to nonhuman apes, potentially suggesting regular bouts of both climbing and terrestrial bipedalism. Our results demonstrate distinct morphological differences, linked to behavioral differences between Australopithecus and later hominins in South Africa and contribute to the increasing evidence of locomotor diversity within the hominin clade.


Assuntos
Hominidae/fisiologia , Animais , Antropologia , Evolução Biológica , Fêmur/anatomia & histologia , Fêmur/fisiologia , Fósseis/história , História Antiga , Hominidae/anatomia & histologia , Humanos , Locomoção , África do Sul
16.
J Anat ; 234(5): 679-693, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30793309

RESUMO

Studies of femoral trabecular structure have shown that the orientation and volume of bone are associated with variation in loading and could be informative about individual joint positioning during locomotion. In this study, we analyse for the first time trabecular bone patterns throughout the femoral head using a whole-epiphysis approach to investigate how potential trabecular variation in humans and great apes relates to differences in locomotor modes. Trabecular architecture was analysed using microCT scans of Pan troglodytes (n = 20), Gorilla gorilla (n = 14), Pongo sp. (n = 5) and Homo sapiens (n = 12) in medtool 4.1. Our results revealed differences in bone volume fraction (BV/TV) distribution patterns, as well as overall trabecular parameters of the femoral head between great apes and humans. Pan and Gorilla showed two regions of high BV/TV in the femoral head, consistent with hip posture and loading during two discrete locomotor modes: knuckle-walking and climbing. Most Pongo specimens also displayed two regions of high BV/TV, but these regions were less discrete and there was more variability across the sample. In contrast, Homo showed only one main region of high BV/TV in the femoral head and had the lowest BV/TV, as well as the most anisotropic trabeculae. The Homo trabecular structure is consistent with stereotypical loading with a more extended hip compared with great apes, which is characteristic of modern human bipedalism. Our results suggest that holistic evaluations of femoral head trabecular architecture can reveal previously undetected patterns linked to locomotor behaviour in extant apes and can provide further insight into hip joint loading in fossil hominins and other primates.


Assuntos
Osso Esponjoso/anatomia & histologia , Cabeça do Fêmur/anatomia & histologia , Hominidae/anatomia & histologia , Animais , Evolução Biológica , Fêmur/anatomia & histologia , Gorilla gorilla/anatomia & histologia , Articulação do Quadril/anatomia & histologia , Humanos , Locomoção/fisiologia , Pan troglodytes/anatomia & histologia , Pongo/anatomia & histologia , Postura/fisiologia
17.
Nat Ecol Evol ; 2(5): 800-809, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29632352

RESUMO

Understanding the timing and character of the expansion of Homo sapiens out of Africa is critical for inferring the colonization and admixture processes that underpin global population history. It has been argued that dispersal out of Africa had an early phase, particularly ~130-90 thousand years ago (ka), that reached only the East Mediterranean Levant, and a later phase, ~60-50 ka, that extended across the diverse environments of Eurasia to Sahul. However, recent findings from East Asia and Sahul challenge this model. Here we show that H. sapiens was in the Arabian Peninsula before 85 ka. We describe the Al Wusta-1 (AW-1) intermediate phalanx from the site of Al Wusta in the Nefud desert, Saudi Arabia. AW-1 is the oldest directly dated fossil of our species outside Africa and the Levant. The palaeoenvironmental context of Al Wusta demonstrates that H. sapiens using Middle Palaeolithic stone tools dispersed into Arabia during a phase of increased precipitation driven by orbital forcing, in association with a primarily African fauna. A Bayesian model incorporating independent chronometric age estimates indicates a chronology for Al Wusta of ~95-86 ka, which we correlate with a humid episode in the later part of Marine Isotope Stage 5 known from various regional records. Al Wusta shows that early dispersals were more spatially and temporally extensive than previously thought. Early H. sapiens dispersals out of Africa were not limited to winter rainfall-fed Levantine Mediterranean woodlands immediately adjacent to Africa, but extended deep into the semi-arid grasslands of Arabia, facilitated by periods of enhanced monsoonal rainfall.


Assuntos
Fósseis , Migração Humana , Arqueologia , Meio Ambiente , Humanos , Arábia Saudita
18.
R Soc Open Sci ; 3(8): 160328, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27853612

RESUMO

In 1912, palaeontologist Arthur Smith Woodward and amateur antiquarian and solicitor Charles Dawson announced the discovery of a fossil that supposedly provided a link between apes and humans: Eoanthropus dawsoni (Dawson's dawn man). The publication generated huge interest from scientists and the general public. However, 'Piltdown man's' initial celebrity has long been overshadowed by its subsequent infamy as one of the most famous scientific frauds in history. Our re-evaluation of the Piltdown fossils using the latest scientific methods (DNA analyses, high-precision measurements, spectroscopy and virtual anthropology) shows that it is highly likely that a single orang-utan specimen and at least two human specimens were used to create the fake fossils. The modus operandi was found consistent throughout the assemblage (specimens are stained brown, loaded with gravel fragments and restored using filling materials), linking all specimens from the Piltdown I and Piltdown II sites to a single forger-Charles Dawson. Whether Dawson acted alone is uncertain, but his hunger for acclaim may have driven him to risk his reputation and misdirect the course of anthropology for decades. The Piltdown hoax stands as a cautionary tale to scientists not to be led by preconceived ideas, but to use scientific integrity and rigour in the face of novel discoveries.

20.
Ann Hum Biol ; 41(4): 312-22, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24932746

RESUMO

BACKGROUND: Diagnosing Homo sapiens is a critical question in the study of human evolution. Although what constitutes living members of our own species is straightforward, in the fossil record this is still a matter of much debate. The issue is complicated by questions of species diagnoses and ideas about the mode by which a new species is born, by the arguments surrounding the behavioural and cognitive separateness of the species, by the increasing appreciation of variation in the early African H. sapiens record and by new DNA evidence of hybridization with extinct species. METHODS AND RESULTS: This study synthesizes thinking on the fossils, archaeology and underlying evolutionary models of the last several decades with recent DNA results from both H. sapiens and fossil species. CONCLUSION: It is concluded that, although it may not be possible or even desirable to cleanly partition out a homogenous morphological description of recent H. sapiens in the fossil record, there are key, distinguishing morphological traits in the cranium, dentition and pelvis that can be usefully employed to diagnose the H. sapiens lineage. Increasing advances in retrieving and understanding relevant genetic data provide a complementary and perhaps potentially even more fruitful means of characterizing the differences between H. sapiens and its close relatives.


Assuntos
Evolução Biológica , DNA/análise , Fósseis/anatomia & histologia , Hibridização Genética , Arqueologia , Humanos , Fenótipo
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