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1.
AIDS Educ Prev ; 33(4): 325-344, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34370571

RESUMO

Increasing access to pre-exposure prophylaxis (PrEP) in primary care settings for patients who may be at risk for HIV could help to increase PrEP uptake, which has remained low among certain key risk populations. The current study conducted interviews with primary care providers identified from national claims data as having either high or low likelihood of serving PrEP-eligible patients based on their prescribing practices for other sexually transmitted infections. The study yielded important information about primary care providers' knowledge, attitudes, and beliefs about PrEP, as well as the barriers and facilitators to prescribing PrEP. Key recommendations for a provider-focused intervention to increase PrEP prescribing among primary care providers, including increasing patient education to increase demand from providers, enhancing provider education, leveraging technology, and instituting standardized sexual health checks, are provided with the goal of informing network-based interventions.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Profilaxia Pré-Exposição , Fármacos Anti-HIV/uso terapêutico , Atitude do Pessoal de Saúde , Infecções por HIV/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Atenção Primária à Saúde , Inquéritos e Questionários
2.
Vaccine ; 39(40): 5737-5740, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34456072

RESUMO

A health care provider's vaccination recommendation is one of the most important factors influencing parents' decisions about whether to vaccinate their children. Unfortunately, vaccine hesitancy is associated with mistrust of health care providers and the medical system. We conducted a survey of 2440 adults through the RAND American Life Panel in 2019. Respondents were asked to rate their trust in pediatricians, OB/GYNs, doulas, midwives, lactation consultants, friends and family for information about childhood vaccines. Respondents were also asked about willingness to vaccinate a hypothetical child as a measure of vaccine hesitancy. We used principal component analysis to characterize variance in responses on trust items and logistic regression to model the relationship between trust and vaccine hesitancy. Vaccine hesitancy was associated with: (1) lower overall trust; (2) reduced trust in OB/GYNs and pediatricians and greater trust in doulas, midwives, and lactation consultants; and (3) greater trust in friends and family.

3.
BMC Health Serv Res ; 21(1): 777, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34362369

RESUMO

BACKGROUND: Policies target networks of providers who treat people with mental illnesses, but little is known about the empirical structures of these networks and related variation in patient care. The goal of this paper is to describe networks of providers who treat adults with mental illness in a multi-payer database based medical claims data in a U.S. state. METHODS: Provider networks were identified and characterized using paid inpatient, outpatient and pharmacy claims related to care for people with a mental health diagnosis from an all-payer claims dataset that covers both public and private payers. RESULTS: Three nested levels of network structures were identified: an overall network, which included 21% of providers (N = 8256) and 97% of patients (N = 476,802), five communities and 24 sub-communities. Sub-communities were characterized by size, provider composition, continuity-of-care (CoC), and network structure measures including mean number of connections per provider (degree) and average number of connections who were connected to each other (transitivity). Sub-community size was positively associated with number of connections (r = .37) and the proportion of psychiatrists (r = .41) and uncorrelated with network transitivity (r = -.02) and continuity of care (r = .00). Network transitivity was not associated with CoC after adjustment for provider type, number of patients, and average connection CoC (p = .85). CONCLUSIONS: These exploratory analyses suggest that network analysis can provide information about the networks of providers that treat people with mental illness that is not captured in traditional measures and may be useful in designing, implementing, and studying interventions to improve systems of care. Though initial results are promising, additional empirical work is needed to develop network-based measures and tools for policymakers.


Assuntos
Pessoal de Saúde , Transtornos Mentais , Adulto , Continuidade da Assistência ao Paciente , Humanos , Transtornos Mentais/terapia , Assistência ao Paciente
4.
PLoS One ; 15(10): e0239826, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33031405

RESUMO

Over the past decade, the percentage of adults in the United States who use some form of social media has roughly doubled, increasing from 36 percent in early 2009 to 72 percent in 2019. There has been a corresponding increase in research aimed at understanding opinions and beliefs that are expressed online. However, the generalizability of findings from social media research is a subject of ongoing debate. Social media platforms are conduits of both information and misinformation about vaccines and vaccine hesitancy. Our research objective was to examine whether we can draw similar conclusions from Twitter and national survey data about the relationship between vaccine hesitancy and a broader set of beliefs. In 2018 we conducted a nationally representative survey of parents in the United States informed by a literature review to ask their views on a range of topics, including vaccine side effects, conspiracy theories, and understanding of science. We developed a set of keyword-based queries corresponding to each of the belief items from the survey and pulled matching tweets from 2017. We performed the data pull of the most recent full year of data in 2018. Our primary measures of belief covariation were the loadings and scores of the first principal components obtained using principal component analysis (PCA) from the two sources. We found that, after using manually coded weblinks in tweets to infer stance, there was good qualitative agreement between the first principal component loadings and scores using survey and Twitter data. This held true after we took the additional processing step of resampling the Twitter data based on the number of topics that an individual tweeted about, as a means of correcting for differential representation for elicited (survey) vs. volunteered (Twitter) beliefs. Overall, the results show that analyses using Twitter data may be generalizable in certain contexts, such as assessing belief covariation.


Assuntos
Opinião Pública , Mídias Sociais/estatística & dados numéricos , Recusa de Vacinação/estatística & dados numéricos , Comunicação , Humanos , Inquéritos e Questionários , Estados Unidos
5.
Nat Hum Behav ; 4(3): 265-269, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31792400

RESUMO

National democracy is a rare thing in human history and its stability has long been tied to the cultural values of citizens. Yet it has not been established whether changing cultural values made modern democracy possible or whether those values were a response to democratic institutions. Here we combine longitudinal data and cohort information of nearly 500,000 individuals from 109 nations to track the co-evolution of democratic values and institutions over the last century. We find that cultural values of openness towards diversity predict a shift towards democracy and that nations with low institutional confidence are prone to political instability. In addition, the presence of democratic institutions did not predict any substantive changes in the measured cultural values. These results hold accounting for other factors, including gross domestic product per capita and non-independence between nations due to shared cultural ancestry. Cultural values lead to, rather than follow, the emergence of democracy. This indicates that current stable democracies will be under threat, should cultural values of openness to diversity and institutional confidence substantially decline.


Assuntos
Cultura , Democracia , Governo , Produto Interno Bruto , Valores Sociais , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Diversidade Cultural , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Confiança , Adulto Jovem
6.
Vaccine ; 37(45): 6793-6802, 2019 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-31562000

RESUMO

BACKGROUND: While childhood vaccines are safe and effective, some parents remain hesitant to vaccinate their children, which has led to outbreaks of vaccine preventable diseases. The goal of this systematic review was to identify and summarize the range of beliefs around childhood vaccines elicited using open-ended questions, which are better suited for discovering beliefs compared to closed-ended questions. METHODS: PubMed, Embase, and PsycINFO were searched using keywords for childhood vaccines, decision makers, beliefs, and attitudes to identify studies that collected primary data using a variety of open-ended questions regarding routine childhood vaccine beliefs in the United States. Study designs, population characteristics, vaccine types, and vaccine beliefs were abstracted. We conducted a qualitative analysis to conceptualize beliefs into themes and generated descriptive statistics. RESULTS: Of 1727 studies identified, 71 were included, focusing largely on parents (including in general, and those who were vaccine hesitant or at risk of hesitancy). Seven themes emerged: Adverse effects was most prominent, followed by mistrust, perceived lack of necessity, pro-vaccine opinions, skepticism about effectiveness, desire for autonomy, and morality concerns. The most commonly described beliefs included that vaccines can cause illnesses; a child's immune system can be overwhelmed if receiving too many vaccines at once; vaccines contain harmful ingredients; younger children are more susceptible to vaccine adverse events; the purpose of vaccines is profit-making; and naturally developed immunity is better than that acquired from vaccines. Nearly a third of the studies exclusively assessed minority populations, and more than half of the studies examined beliefs only regarding HPV vaccine. CONCLUSIONS: Few studies used open-ended questions to elicit beliefs about vaccines. Many of the studies that did so, focused on HPV vaccine. Concerns about vaccine safety were the most commonly stated beliefs about childhood vaccines, likely because studies were designed to capture barriers and challenges to vaccination.


Assuntos
Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Vacinação/psicologia , Tomada de Decisões , Feminino , Humanos , Imunização/psicologia , Imunização/estatística & dados numéricos , Masculino , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Estados Unidos , Vacinação/estatística & dados numéricos
7.
Neuromolecular Med ; 21(4): 401-413, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31313065

RESUMO

Frontal infarcts can produce cognitive impairments that affect an individual's ability to function in everyday life. However, the precise types of deficits, and their underlying mechanisms, are not well-understood. Here we used a prefrontal photothrombotic stroke model in C57BL/6J mice to characterise specific cognitive changes that occur in the 6 weeks post-stroke. Behavioural experiments were paired with in vivo electrophysiology to assess whether changes in oscillatory communication between the prefrontal cortex (PFC) and the hippocampus (HPC) mirrored any observed behavioural changes. We found that mice in the stroke group exhibited a delayed onset impairment in tasks of spatial working memory (object location recognition and Y-maze) and that this correlated with reduced PFC-HPC theta band coherence (5-12 Hz) during the task. In the open field, mice in the stroke group exhibited hyperactivity as compared to controls, and stroke animals also exhibited significantly higher beta band activity (13-30 Hz) in the PFC and the HPC. Taken together our results suggest that infarcts in the PFC result in PFC-HPC oscillatory communication changes in the theta and beta bands, correlating with altered performance in spatial memory and open field tasks respectively. Of particular interest, early open field changes in PFC beta band power post-stroke correlated to later-stage spatial memory impairments, highlighting this as a potential biomarker for detecting when spatial memory impairments are likely to occur.


Assuntos
Hipocampo/fisiopatologia , Aprendizagem em Labirinto/fisiologia , Transtornos da Memória/etiologia , Córtex Pré-Frontal/fisiopatologia , Acidente Vascular Cerebral/complicações , Animais , Ritmo beta , Eletrodos Implantados , Comportamento Exploratório/fisiologia , Masculino , Transtornos da Memória/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Vias Neurais/fisiopatologia , Teste de Campo Aberto/fisiologia , Distribuição Aleatória , Reconhecimento Psicológico/fisiologia , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/psicologia , Ritmo Teta
8.
Rand Health Q ; 7(1): 10, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29057160

RESUMO

When engaging in behaviors that may entail risks or outcomes that are unknown or uncertain, individuals often look beyond their own experiences (including past behaviors and subsequent outcomes) to consider the experiences of others in their immediate social networks. This social influence at the micro-scale (i.e., the way in which individuals are influenced by their immediate social networks) can affect change in the greater social web in such a way that social networks may have profound effects on decisionmaking at the population level. Such micro-level social influence is central to many theories of individual decisionmaking and behavior. Observations of population-level dynamics at the macro-level demonstrate the end result of these processes-for example, over time, people's behavior tends to look more like that of their peers. This article describes a general agent-based model (ABM) for studying social influence, and uses that general ABM to explore the relationship between micro-influence and macro-dynamics for broad classes of problems. We also describe an approach to tailor the general ABM to model a specific behavior influenced by social learning, which we illustrate using surveys designed to inform the ABM. The framework we developed could be useful for studying any system in which social learning may occur. But while our general ABM can produce dynamics reminiscent of those that might result from many different types of behaviors, it will typically need to be tailored when used to model any particular behavior.

9.
PLoS One ; 11(4): e0152979, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27110713

RESUMO

Political and economic risks arise from social phenomena that spread within and across countries. Regime changes, protest movements, and stock market and default shocks can have ramifications across the globe. Quantitative models have made great strides at predicting these events in recent decades but incorporate few explicitly measured cultural variables. However, in recent years cultural evolutionary theory has emerged as a major paradigm to understand the inheritance and diffusion of human cultural variation. Here, we combine these two strands of research by proposing that measures of socio-linguistic affiliation derived from language phylogenies track variation in cultural norms that influence how political and economic changes diffuse across the globe. First, we show that changes over time in a country's democratic or autocratic character correlate with simultaneous changes among their socio-linguistic affiliations more than with changes of spatially proximate countries. Second, we find that models of changes in sovereign default status favor including socio-linguistic affiliations in addition to spatial data. These findings suggest that better measurement of cultural networks could be profoundly useful to policy makers who wish to diversify commercial, social, and other forms of investment across political and economic risks on an international scale.


Assuntos
Evolução Cultural , Economia , Política , Humanos , Filogenia
10.
Rand Health Q ; 5(4): 14, 2016 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-28083424

RESUMO

The Veterans Access, Choice, and Accountability Act of 2014 addressed the need for access to timely, high-quality health care for veterans. Section 201 of the legislation called for an independent assessment of various aspects of veterans' health care. The RAND Corporation was tasked with an assessment of the Department of Veterans Affairs (VA) current and projected health care capabilities and resources. An examination of data from a variety of sources, along with a survey of VA medical facility leaders, revealed the breadth and depth of VA resources and capabilities: fiscal resources, workforce and human resources, physical infrastructure, interorganizational relationships, and information resources. The assessment identified barriers to the effective use of these resources and capabilities. Analysis of data on access to VA care and the quality of that care showed that almost all veterans live within 40 miles of a VA health facility, but fewer have access to VA specialty care. Veterans usually receive care within 14 days of their desired appointment date, but wait times vary considerably across VA facilities. VA has long played a national leadership role in measuring the quality of health care. The assessment showed that VA health care quality was as good or better on most measures compared with other health systems, but quality performance lagged at some VA facilities. VA will require more resources and capabilities to meet a projected increase in veterans' demand for VA care over the next five years. Options for increasing capacity include accelerated hiring, full nurse practice authority, and expanded use of telehealth.

11.
PLoS One ; 8(2): e55234, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23418436

RESUMO

Studies of social networks, mapped using self-reported contacts, have demonstrated the strong influence of social connections on the propensity for individuals to adopt or maintain healthy behaviors and on their likelihood to adopt health risks such as obesity. Social network analysis may prove useful for businesses and organizations that wish to improve the health of their populations by identifying key network positions. Health traits have been shown to correlate across friendship ties, but evaluating network effects in large coworker populations presents the challenge of obtaining sufficiently comprehensive network data. The purpose of this study was to evaluate methods for using online communication data to generate comprehensive network maps that reproduce the health-associated properties of an offline social network. In this study, we examined three techniques for inferring social relationships from email traffic data in an employee population using thresholds based on: (1) the absolute number of emails exchanged, (2) logistic regression probability of an offline relationship, and (3) the highest ranked email exchange partners. As a model of the offline social network in the same population, a network map was created using social ties reported in a survey instrument. The email networks were evaluated based on the proportion of survey ties captured, comparisons of common network metrics, and autocorrelation of body mass index (BMI) across social ties. Results demonstrated that logistic regression predicted the greatest proportion of offline social ties, thresholding on number of emails exchanged produced the best match to offline network metrics, and ranked email partners demonstrated the strongest autocorrelation of BMI. Since each method had unique strengths, researchers should choose a method based on the aspects of offline behavior of interest. Ranked email partners may be particularly useful for purposes related to health traits in a social network.


Assuntos
Comunicação , Correio Eletrônico , Internet , Rede Social , Local de Trabalho , Adulto , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Autorrelato , Comportamento Social
12.
Hum Nat ; 23(2): 218-49, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22623139

RESUMO

Recent research on the evolution of religion has focused on whether religion is an unselected by-product of evolutionary processes or if it is instead an adaptation by natural selection. Adaptive hypotheses for religion include direct fitness benefits from improved health and indirect fitness benefits mediated by costly signals and/or cultural group selection. Herein, I propose that religious denominations achieve indirect fitness gains for members through the use of ecologically arbitrary beliefs, rituals, and moral rules that function as recognition markers of cultural inheritance analogous to kin and species recognition of genetic inheritance in biology. This recognition signal hypotheses could act in concert with either costly signaling or cultural group selection to produce evolutionarily altruistic behaviors within denominations. Using a cultural phylogenetic analysis, I show that a large set of religious behaviors among extant Christian denominations supports the prediction of the recognition signal hypothesis that characters change more frequently near historical schisms. By incorporating demographic data into the model, I show that more-distinctive denominations, as measured through dissimilar characteristics, appear to be protected from intrusion by nonmembers in mixed-denomination households, and that they may be experiencing greater biological growth of their populations even in the present day.


Assuntos
Adaptação Fisiológica , Cristianismo , Evolução Cultural , Comportamento Cooperativo , Demografia , Humanos , Modelos Teóricos , Variações Dependentes do Observador , Filogenia
13.
Am J Phys Anthropol ; 147(3): 409-16, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22281983

RESUMO

Activity period plays a central role in studies of primate origins and adaptations, yet fundamental questions remain concerning the evolutionary history of primate activity period. Lemurs are of particular interest because they display marked variation in activity period, with some species exhibiting completely nocturnal or diurnal lifestyles, and others distributing activity throughout the 24-h cycle (i.e., cathemerality). Some lines of evidence suggest that cathemerality in lemurs is a recent and transient evolutionary state (i.e., the evolutionary disequilibrium hypothesis), while other studies indicate that cathemerality is a stable evolutionary strategy with a more ancient history. Debate also surrounds activity period in early primate evolution, with some recent studies casting doubt on the traditional hypothesis that basal primates were nocturnal. Here, we used Bayesian phylogenetic methods to reconstruct activity period at key points in primate evolution. Counter to the evolutionary disequilibrium hypothesis, the most recent common ancestor of Eulemur was reconstructed as cathemeral at ∼9-13 million years ago, indicating that cathemerality in lemurs is a stable evolutionary strategy. We found strong evidence favoring a nocturnal ancestor for all primates, strepsirrhines and lemurs, which adds to previous findings based on parsimony by providing quantitative support for these reconstructions. Reconstructions for the haplorrhine ancestor were more equivocal, but diurnality was favored for simian primates. We discuss the implications of our models for the evolutionary disequilibrium hypothesis, and we identify avenues for future research that would provide new insights into the evolution of cathemerality in lemurs.


Assuntos
Evolução Biológica , Lemur/fisiologia , Atividade Motora/fisiologia , Filogenia , Animais , Teorema de Bayes , Ritmo Circadiano , Lemur/genética , Atividade Motora/genética
14.
Am J Primatol ; 74(4): 299-314, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21769906

RESUMO

The frequency of anointing bouts and the materials used for self- and social anointing vary across capuchin species in captivity, but there is little published data on capuchin anointing in the wild. Here we present previously unpublished data on anointing behaviors from capuchin monkey populations at ten different field sites and incorporate these data into a review of the anointing literature for captive and wild capuchins. Using a comparative phylogenetic framework, we test four hypotheses derived primarily from captive literature for variation in anointing between wild untufted capuchins (Cebus) and tufted capuchins (Sapajus), including that (1) the frequency of anointing is higher in Cebus, (2) Cebus uses a higher proportion of plant species to insect species for anointing compared with Sapajus, (3) anointing material diversity is higher in Cebus, and (4) social indices of anointing are higher in Cebus. We found that wild Cebus anoints more with plant parts, including fruits, whereas wild Sapajus anoints more with ants and other arthropods. Cebus capucinus in particular uses more plant species per site for anointing compared with other capuchins and may specialize in anointing as an activity independent from foraging, whereas most other capuchin species tend to eat the substances they use for anointing. In agreement with captive studies, we found evidence that wild Cebus anoints at a significantly higher frequency than Sapajus. However, contrary to the captive literature, we found no difference in the range of sociality for anointing between Cebus and Sapajus in the wild. We review anointing in the context of other Neotropical primate rubbing behaviors and consider the evidence for anointing as self-medication; as a mechanism for enhanced sociality; and as a behavioral response to chemical stimuli.


Assuntos
Animais Selvagens/fisiologia , Comportamento Animal , Cebus/fisiologia , Cebus/psicologia , Comportamento Social , Animais , Cebus/classificação , Filogenia
15.
Anim Cogn ; 15(2): 223-38, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21927850

RESUMO

Now more than ever animal studies have the potential to test hypotheses regarding how cognition evolves. Comparative psychologists have developed new techniques to probe the cognitive mechanisms underlying animal behavior, and they have become increasingly skillful at adapting methodologies to test multiple species. Meanwhile, evolutionary biologists have generated quantitative approaches to investigate the phylogenetic distribution and function of phenotypic traits, including cognition. In particular, phylogenetic methods can quantitatively (1) test whether specific cognitive abilities are correlated with life history (e.g., lifespan), morphology (e.g., brain size), or socio-ecological variables (e.g., social system), (2) measure how strongly phylogenetic relatedness predicts the distribution of cognitive skills across species, and (3) estimate the ancestral state of a given cognitive trait using measures of cognitive performance from extant species. Phylogenetic methods can also be used to guide the selection of species comparisons that offer the strongest tests of a priori predictions of cognitive evolutionary hypotheses (i.e., phylogenetic targeting). Here, we explain how an integration of comparative psychology and evolutionary biology will answer a host of questions regarding the phylogenetic distribution and history of cognitive traits, as well as the evolutionary processes that drove their evolution.


Assuntos
Cognição , Filogenia , Psicologia Comparada , Animais , Pesquisa Comportamental , Evolução Biológica , Cognição/fisiologia , Hominidae/psicologia , Primatas/psicologia
16.
Am J Primatol ; 74(4): 287-98, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22038882

RESUMO

Researchers of capuchin monkeys have noted stereotyped body postures, facial expressions, and vocalizations that accompany copulations in this genus. Notable variations in these sexual behaviors are observed across capuchin species. Although several hypotheses exist to explain variation in the duration and vigor of sexual behaviors across species, there is no proposed explanation for variation in the forms of these behaviors. I hypothesized that the forms of sexual behaviors function as recognition signals of conspecific mates. Such signals are adaptive when F1 hybrids exhibit reduced fitness compared with nonhybrid offspring. Recent evidence from nonprimate taxa supports the existence of species recognition signals during mating. Using newly observed sexual behaviors for Cebus albifrons and a recent phylogeny of capuchins, I found significant support for a key prediction of the conspecific mate recognition hypothesis: evolutionary changes in sexual behaviors were associated with speciation. Given the resultant best model for evolution of sexual behaviors, I reconstructed the ancestral pattern of sexual behaviors for extant capuchin species (genera Cebus and Sapajus). This reconstruction suggests that the extreme female proceptivity of tufted capuchin monkeys may function to increase female reproductive choices in the context of sperm-limited males (genus Sapajus).


Assuntos
Cebus/classificação , Cebus/psicologia , Comportamento Sexual Animal , Animais , Feminino , Masculino
17.
PLoS One ; 6(4): e14810, 2011 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-21559083

RESUMO

BACKGROUND: Archaeologists and anthropologists have long recognized that different cultural complexes may have distinct descent histories, but they have lacked analytical techniques capable of easily identifying such incongruence. Here, we show how bayesian phylogenetic analysis can be used to identify incongruent cultural histories. We employ the approach to investigate Iranian tribal textile traditions. METHODS: We used bayes factor comparisons in a phylogenetic framework to test two models of cultural evolution: the hierarchically integrated system hypothesis and the multiple coherent units hypothesis. In the hierarchically integrated system hypothesis, a core tradition of characters evolves through descent with modification and characters peripheral to the core are exchanged among contemporaneous populations. In the multiple coherent units hypothesis, a core tradition does not exist. Rather, there are several cultural units consisting of sets of characters that have different histories of descent. RESULTS: For the Iranian textiles, the bayesian phylogenetic analyses supported the multiple coherent units hypothesis over the hierarchically integrated system hypothesis. Our analyses suggest that pile-weave designs represent a distinct cultural unit that has a different phylogenetic history compared to other textile characters. CONCLUSIONS: The results from the Iranian textiles are consistent with the available ethnographic evidence, which suggests that the commercial rug market has influenced pile-rug designs but not the techniques or designs incorporated in the other textiles produced by the tribes. We anticipate that bayesian phylogenetic tests for inferring cultural units will be of great value for researchers interested in studying the evolution of cultural traits including language, behavior, and material culture.


Assuntos
Evolução Cultural , Têxteis , Animais , Antropologia/métodos , Arqueologia/métodos , Teorema de Bayes , Cultura , Humanos , Irã (Geográfico) , Modelos Teóricos , Filogenia , Alinhamento de Sequência , Análise de Sequência de DNA
18.
Am J Phys Anthropol ; 145(3): 382-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21469077

RESUMO

Numerous lines of evidence suggest that Homo sapiens evolved as a distinct species in Africa by 150,000 years before the present (BP) and began major migrations out-of-Africa ∼50,000 BP. By 20,000 BP, our species had effectively colonized the entire Old World, and by 12,000 BP H. sapiens had a global distribution. We propose that this rapid migration into new habitats selected for individuals with low reactivity to novel stressors. Certain dopamine receptor D4 (DRD4) polymorphisms are associated with low neuronal reactivity and increased exploratory behavior, novelty seeking, and risk taking, collectively considered novelty-seeking trait (NS). One previous report (Chen et al.: Evol Hum Behav 20 (1999) 309-324) demonstrated a correlation between migratory distance and the seven-repeat (7R) VNTR DRD4 allele at exon 3 for human populations. This study, however, failed to account for neutral genetic processes (drift and admixture) that might create such a correlation in the absence of natural selection. Furthermore, additional loci surrounding DRD4 are now recognized to influence NS. Herein we account for neutral genetic structure by modeling the nonindependence of neutral allele frequencies between human populations. We retest the DRD4 exon 3 alleles, and also test two other loci near DRD4 that are associated with NS. We conclude there is an association between migratory distance and DRD4 exon 3 2R and 7R alleles that cannot be accounted for by neutral genetic processes alone.


Assuntos
Comportamento Exploratório , Genética Populacional , Polimorfismo Genético/genética , Grupos Populacionais/genética , Receptores de Dopamina D4/genética , Emigração e Imigração , Frequência do Gene , Humanos , Análise dos Mínimos Quadrados , Assunção de Riscos , Seleção Genética
19.
Proc Biol Sci ; 278(1709): 1256-63, 2011 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-20943699

RESUMO

Body mass is thought to influence diversification rates, but previous studies have produced ambiguous results. We investigated patterns of diversification across 100 trees obtained from a new Bayesian inference of primate phylogeny that sampled trees in proportion to their posterior probabilities. First, we used simulations to assess the validity of previous studies that used linear models to investigate the links between IUCN Red List status and body mass. These analyses support the use of linear models for ordinal ranked data on threat status, and phylogenetic generalized linear models revealed a significant positive correlation between current extinction risk and body mass across our tree block. We then investigated historical patterns of speciation and extinction rates using a recently developed maximum-likelihood method. Specifically, we predicted that body mass correlates positively with extinction rate because larger bodied organisms reproduce more slowly, and body mass correlates negatively with speciation rate because smaller bodied organisms are better able to partition niche space. We failed to find evidence that extinction rates covary with body mass across primate phylogeny. Similarly, the speciation rate was generally unrelated to body mass, except in some tests that indicated an increase in the speciation rate with increasing body mass. Importantly, we discovered that our data violated a key assumption of sample randomness with respect to body mass. After correcting for this bias, we found no association between diversification rates and mass.


Assuntos
Tamanho Corporal , Extinção Biológica , Especiação Genética , Primatas/anatomia & histologia , Animais , Biodiversidade , Fósseis , Filogenia , Primatas/fisiologia , Incerteza
20.
Am Anthropol ; 112(2): 257-269, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21135912

RESUMO

The study of social learning in captivity and behavioral traditions in the wild are two burgeoning areas of research, but few empirical studies have tested how learning mechanisms produce emergent patterns of tradition. Studies have examined how social learning mechanisms that are cognitively complex and possessed by few species, such as imitation, result in traditional patterns, yet traditional patterns are also exhibited by species that may not possess such mechanisms. We propose an explicit model of how stimulus enhancement and reinforcement learning could interact to produce traditions. We tested the model experimentally with tufted capuchin monkeys (Cebus apella), which exhibit traditions in the wild but have rarely demonstrated imitative abilities in captive experiments. Monkeys showed both stimulus enhancement learning and a habitual bias to perform whichever behavior first obtained them a reward. These results support our model that simple social learning mechanisms combined with reinforcement can result in traditional patterns of behavior.

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