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1.
Ecol Lett ; 27(5): e14443, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38803140

RESUMO

Recent proliferation of GPS technology has transformed animal movement research. Yet, time-series data from this recent technology rarely span beyond a decade, constraining longitudinal research. Long-term field sites hold valuable historic animal location records, including hand-drawn maps and semantic descriptions. Here, we introduce a generalised workflow for converting such records into reliable location data to estimate home ranges, using 30 years of sleep-site data from 11 white-faced capuchin (Cebus imitator) groups in Costa Rica. Our findings illustrate that historic sleep locations can reliably recover home range size and geometry. We showcase the opportunity our approach presents to resolve open questions that can only be addressed with very long-term data, examining how home ranges are affected by climate cycles and demographic change. We urge researchers to translate historical records into usable movement data before this knowledge is lost; it is essential to understanding how animals are responding to our changing world.


Assuntos
Cebus , Mudança Climática , Animais , Costa Rica , Cebus/fisiologia , Comportamento de Retorno ao Território Vital , Sistemas de Informação Geográfica , Dinâmica Populacional , Demografia
2.
Am J Primatol ; 86(4): e23594, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38196199

RESUMO

Tool-using primates often show sex differences in both the frequency and efficiency of tool use. In species with sex-biased dispersal, such within-group variation likely shapes patterns of cultural transmission of tool-use traditions between groups. On the Panamanian islands of Jicarón and Coiba, a population of white-faced capuchins (Cebus capucinus imitator)-some of which engage in habitual stone tool use-provide an opportunity to test hypotheses about why such sex-biases arise. On Jicarón, we have only observed males engaging in stone tool use, whereas on Coiba, both sexes are known to use tools. Using 5 years of camera trap data, we provide evidence that this variation likely reflects a sex difference in tool use rather than a sampling artifact, and then test hypotheses about the factors driving this pattern. Differences in physical ability or risk-aversion, and competition over access to anvils do not account for the sex-differences in tool-use we observe. Our data show that adult females are physically capable of stone tool use: adult females on Coiba and juveniles on Jicarón smaller than adult females regularly engage in tool use. Females also have ample opportunity to use tools: the sexes are equally terrestrial, and competition over anvils is low. Finally, females rarely scrounge on left-over food items either during or after tool-using events, suggesting they are not being provisioned by males. Although it remains unclear why adult white-faced capuchin females on Jicarón do not use stone-tools, our results illustrate that such sex biases in socially learned behaviors can arise even in the absence of obvious physical, environmental, and social constraints. This suggests that a much more nuanced understanding of the differences in social structure, diet, and dispersal patterns are needed to explain why sex-biases in tool use arise in some populations but not in others.


Assuntos
Cebus capucinus , Comportamento de Utilização de Ferramentas , Feminino , Animais , Masculino , Cebus , Comportamento Alimentar , Alimentos
3.
R Soc Open Sci ; 10(9): 230355, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37736530

RESUMO

Terrestrial mammals exploiting coastal resources must cope with the challenge that resource availability and accessibility fluctuate with tidal cycles. Tool use can improve foraging efficiency and provide access to structurally protected resources that are otherwise unavailable (e.g. molluscs and fruits). To understand how variable accessibility of valuable resources shapes behavioural patterns, and whether tool use aids in the efficient exploitation of intertidal resources, we compared the relationship between tidal cycles and activity patterns of tool-using versus non-tool-using groups of white-faced capuchin monkeys on Jicarón Island in Coiba National Park, Panama. Although tool use on Jicarón is localized to a small stretch of coast (approx. 1 km), all coastal groups forage on intertidal resources. Using more than 5 years of camera trap data at varying distances from the coast, we found that capuchins on Jicarón showed increased coastal activity during specific parts of the tidal cycle, and that this relationship differed between tool-using and non-tool-using groups, as well as between seasons. Activity patterns of tool-using capuchins were more strongly and consistently tied to tidal cycles compared with non-tool-users, indicating that tool use might allow for more efficient exploitation of tidal resources. Our findings highlight the potential of tool use to aid niche expansion.

4.
J Anim Ecol ; 92(8): 1532-1544, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36268710

RESUMO

Two-option choice experimental designs are the most commonly employed framework for identifying evidence of social learning or social learning strategies in captive and wild populations. In nature, however, animals often choose from more than two behaviours, and multiple innovations may arise simultaneously. Studies of animal social learning are often constrained by small sample sizes, which limit researchers' ability to convincingly identify the proposed social learning strategy responsible for behavioural choice. In this study, I examine whether expanding behavioural options from k = 2 to k > 2 and increasing sample size affects inferential power in identifying social learning strategies. I focus on three frequency-dependent learning strategies: conformist transmission, unbiased transmission and anti-conformist transmission. I simulate 100 datasets for 72 parameter combinations, yielding 7200 simulations. I evaluate number of options (k = 2, 3, 4, 5), population size (n = 5, 10, 25, 50, 100, 250) and the logarithmic strength of frequency dependence (log(f) = log(1∕3), log(1), log(3)). I then fit a Bayesian social learning model to simulated data to evaluate the percent of the posterior consistent with type of frequency dependence, posterior standard deviations, highest posterior density intervals and posterior medians relative to the true simulated value of log(f). I show that increasing the number of options an animal can choose from increases the accuracy and certainty of identifying the type and magnitude of frequency-dependent social learning. These effects are particularly pronounced at small to intermediate sample sizes, which are common in empirical studies of animal social learning. These findings suggest that knowing what an animal did not choose is equally important as knowing what an animal did choose when identifying social learning strategies. By strategically increasing the number of behaviours from which an animal can choose, researchers can increase inferential power in identifying social learning strategies without increasing sample size, that is, adding additional animals or collecting more data.


Assuntos
Conformidade Social , Aprendizado Social , Animais , Teorema de Bayes , Comportamento Social , Aprendizagem
5.
Proc Biol Sci ; 289(1980): 20221001, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35946158

RESUMO

Culture is an outcome of both the acquisition of knowledge about behaviour through social transmission, and its subsequent production by individuals. Acquisition and production are often discussed or modelled interchangeably, yet to date no study has explored the consequences of their interaction for cultural diffusions. We present a generative model that integrates the two, and ask how variation in production rules might influence diffusion dynamics. Agents make behavioural choices that change as they learn from their productions. Their repertoires may also change, and the acquisition of behaviour is conditioned on its frequency. We analyse the diffusion of a novel behaviour through social networks, yielding generalizable predictions of how individual-level behavioural production rules influence population-level diffusion dynamics. We then investigate how linking acquisition and production might affect the performance of two commonly used inferential models for social learning; network-based diffusion analysis, and experience-weighted attraction models. We find that the influence that production rules have on diffusion dynamics has consequences for how inferential methods are applied to empirical data. Our model illuminates the differences between social learning and social influence, demonstrates the overlooked role of reinforcement learning in cultural diffusions, and allows for clearer discussions about social learning strategies.


Assuntos
Evolução Cultural , Aprendizado Social , Humanos , Comportamento Social
6.
Can J Kidney Health Dis ; 9: 20543581221097455, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35646375

RESUMO

Purpose: Iodinated contrast media is one of the most frequently administered pharmaceuticals. In Canada, over 5.4 million computed tomography (CT) examinations were performed in 2019, of which 50% were contrast enhanced. Acute kidney injury (AKI) occurring after iodinated contrast administration was historically considered a common iatrogenic complication which was managed by screening patients, prophylactic strategies, and follow-up evaluation of renal function. The Canadian Association of Radiologists (CAR) initially published guidelines on the prevention of contrast induced nephropathy in 2007, with an update in 2012. However, new developments in the field have led to the availability of safer contrast agents and changes in clinical practice, prompting a complete revision of the earlier recommendations. Information sources: Published literature, including clinical trials, retrospective cohort series, review articles, and case reports, along with expert opinions from radiologists and nephrologists across Canada. Methods: The leadership of the CAR formed a working group of radiologists and nephrologists with expertise in contrast administration and patient management related to contrast-associated AKI. We conducted a comprehensive review of the published literature to evaluate the evidence about contrast as a cause of AKI, and to inform evidence-based recommendations. Based on the available literature, the working group developed consensus recommendations. Key Findings: The working group developed 21 recommendations, on screening, choice of iodinated contrast media, prophylaxis, medication considerations, and post contrast administration management. The key changes from the 2012 guidelines were (1) Simplification of screening to a simple questionnaire, and not delaying emergent examinations due to a need for creatinine measurements (2) Prophylaxis considerations only for patients with estimated glomerular filtration rate (eGFR) less than 30 mL/min/1.73 m2 (3) Not recommending the routine discontinuation of any drugs to decrease risk of AKI, except metformin when eGFR is less than 30 mL/min/1.73 m2 and (4) Not requiring routine follow up serum creatinine measurements post iodinated contrast administration. Limitations: We did not conduct a formal systematic review or meta-analysis. We did not evaluate our specific suggestions in the clinical environment. Implications: Given the importance of iodinated contrast media use in diagnosis and management, and the low risk of AKI after contrast use, these guidelines aim to streamline the processes around iodinated contrast use in most clinical settings. As newer evidence arises that may change or add to the recommendations provided, the working group will revise these guidelines.


Justification: Les agents de contraste iodés (ACI) sont parmi les produits pharmaceutiques les plus fréquemment administrés. Au Canada, plus de 5,4 millions d'examens de tomodensitométrie (TDM) ont été réalisés en 2019, dont 50 % ont été faits avec un ACI. L'insuffisance rénale aiguë (IRA) survenant après l'administration d'un ACI était historiquement considérée comme une complication iatrogénique fréquente qui était prise en charge par le dépistage des patients, des stratégies prophylactiques et une évaluation de suivi de la fonction rénale. L'Association canadienne des radiologistes (CAR) a publié des lignes directrices pour la prévention de la néphropathie induite par les agents de contraste en 2007 et une mise à jour en 2012. De nouveaux développements sur le terrain ont toutefois mené à la disponibilité d'agents de contraste plus sécuritaires et à des changements dans la pratique clinique, ce qui a entraîné une révision complète des recommandations antérieures. Sources: La littérature publiée, y compris les essais cliniques, les séries de cohortes rétrospectives, les articles-synthèse et les rapports de cas, de même que les opinions d'experts de radiologistes et de néphrologues de partout au Canada. Méthodologie: La direction de la CAR a formé un groupe de travail composé de radiologues et de néphrologues ayant une expertise dans l'administration d'ACI et la gestion de patients atteints d'IRA survenant après l'administration d'un ACI. Le groupe a procédé à une revue complète de la littérature publiée afin d'évaluer les données probantes sur les ACI comme cause de l'IRA et de formuler des recommandations en fonction de celles-ci. Le groupe de travail a élaboré des recommandations consensuelles en se fondant sur la documentation disponible. Principaux résultats: Le groupe de travail a élaboré 21 recommandations sur le dépistage, le choix des agents de contraste iodés, la prophylaxie, les considérations relatives aux médicaments et la gestion post-administration de l'ACI. Les principaux changements par rapport aux lignes directrices de 2012 étaient : (1) de simplifier le dépistage à un simple questionnaire et de ne pas retarder les examens émergents en raison du besoin de mesurer la créatinine; (2) d'avoir des considérations prophylactiques uniquement pour les patients dont le débit de filtration glomérulaire estimé (DFGe) est inférieur à 30 mL/min/1,73 m2; (3) de ne pas recommander l'arrêt des médicaments visant à réduire le risque d'IRA, comme c'est normalement le cas, sauf la metformine lorsque le DFGe est inférieur à 30 mL/min/1,73 m2 et; (4) ne pas demander de mesures de suivi de routine de la créatinine sérique après administration d'un agent de contraste iodé. Limites: Le groupe n'a pas procédé à une revue formelle et systématique de la littérature sur le sujet ni à une méta-analyse. Les suggestions n'ont pas été évaluées dans un environnement clinique. Conclusion: Compte tenu de l'importance des agents de contraste iodés dans le diagnostic et la prise en charge des patients, et du faible risque d'IRA encouru après leur administration, ces recommandations ne visent qu'à simplifier les processus relatifs à l'utilisation des ACI dans la plupart des milieux cliniques. Le groupe de travail révisera ces lignes directrices au fur et à mesure que des éléments de preuve plus récents seront ajoutés aux recommandations fournies.

7.
Sci Rep ; 11(1): 9550, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-34006940

RESUMO

Social learning-learning from others-is the basis for behavioural traditions. Different social learning strategies (SLS), where individuals biasedly learn behaviours based on their content or who demonstrates them, may increase an individual's fitness and generate behavioural traditions. While SLS have been mostly studied in isolation, their interaction and the interplay between individual and social learning is less understood. We performed a field-based open diffusion experiment in a wild primate. We provided two groups of vervet monkeys with a novel food, unshelled peanuts, and documented how three different peanut opening techniques spread within the groups. We analysed data using hierarchical Bayesian dynamic learning models that explore the integration of multiple SLS with individual learning. We (1) report evidence of social learning compared to strictly individual learning, (2) show that vervets preferentially socially learn the technique that yields the highest observed payoff and (3) also bias attention toward individuals of higher rank. This shows that behavioural preferences can arise when individuals integrate social information about the efficiency of a behaviour alongside cues related to the rank of a demonstrator. When these preferences converge to the same behaviour in a group, they may result in stable behavioural traditions.


Assuntos
Chlorocebus aethiops , Animais , Teorema de Bayes , Comportamento Animal , Chlorocebus aethiops/fisiologia , Comportamento Exploratório , Comportamento Alimentar , Comportamento Social , Predomínio Social , Aprendizado Social
8.
Methods Mol Biol ; 2249: 103-124, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33871841

RESUMO

Statistical models are used to study the relationship between exposure and disease while accounting for the potential role of other factors' impact upon outcomes. This adjustment is useful to obtain unbiased estimates of true effects or to predict future outcomes. Statistical models include a systematic and an error component. The systematic component explains the variability of the response variable as a function of the predictors and is summarized in the effect estimates (model coefficients). The error element of the model represents the variability in the data unexplained by the model and is used to build measures of precisions around the point estimates (Confidence Intervals).


Assuntos
Estudos Longitudinais , Modelos Estatísticos , Humanos , Análise Multivariada , Análise de Regressão
9.
Methods Mol Biol ; 2249: 125-165, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33871842

RESUMO

In longitudinal studies, the relationship between exposure and disease can be measured once or multiple times while participants are monitored over time. Traditional regression techniques are used to model outcome data when each epidemiological unit is observed once. These models include generalized linear models for quantitative continuous, discrete, or qualitative outcome responses, and models for time-to-event data. When data come from the same subjects or group of subjects, observations are not independent and the underlying correlation needs to be addressed in the analysis. In these circumstances, extended models are necessary to handle complexities related to clustered data, and repeated measurements of time-varying predictors and/or outcomes.


Assuntos
Estudos Longitudinais , Análise de Sobrevida , Adulto , Fatores Etários , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Análise de Regressão , Projetos de Pesquisa , Adulto Jovem
10.
Methods Mol Biol ; 2249: 193-211, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33871845

RESUMO

Today's clinical practice relies on the application of well-designed clinical research, the gold standard test of an intervention being the randomized controlled trial. Principles of the randomized control trial include emphasis on the principal research question, randomization, blinding; definitions of outcome measures, of inclusion and exclusion criteria, and of co-morbid and confounding factors; enrolling an adequate sample size; planning data management and analysis; preventing challenges to trial integrity such as drop-out, drop-in, and bias. The application of pre-trial planning is stressed to ensure the proper application of epidemiological principles resulting in clinical studies that are feasible and generalizable. In addition, funding strategies and trial team composition are discussed.


Assuntos
Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Projetos de Pesquisa , Viés , Humanos , Modelos Teóricos , Avaliação de Resultados em Cuidados de Saúde , Tamanho da Amostra
11.
Methods Mol Biol ; 2249: 261-280, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33871849

RESUMO

Biomarkers are characteristics that are measured as indicators of normal biological processes, pathogenic processes, or responses to an exposure or intervention, including therapeutic interventions. Biomarkers may serve a number of important uses, particularly in diagnosis and prognosis of disease, and as surrogates for clinical outcomes of disease (i.e., outcomes that measure how patient survives, functions, or feels). Establishing the validity of a given biomarker for a specific role requires the conduct of carefully designed clinical studies in which the biomarker and the outcome of interest are measured independently. The design and analysis of such studies is discussed. Surrogate outcomes in clinical trials consist of events or biomarkers intended to reflect important clinical outcomes. Surrogate outcomes may offer advantages in providing statistically robust estimates of treatment effects with smaller sample sizes. However, to be useful, surrogate outcomes have to be validated to ensure that the effect of therapy on them truly reflects the effect of therapy on the important clinical outcomes of interest.


Assuntos
Biomarcadores/análise , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Humanos , Modelos Estatísticos , Prognóstico , Projetos de Pesquisa , Tamanho da Amostra , Resultado do Tratamento
12.
Methods Mol Biol ; 2249: 319-333, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33871852

RESUMO

As technology advances, diagnostic tests continue to improve and each year, we are presented with new alternatives to standard procedures. Given the plethora of diagnostic alternatives, diagnostic tests must be evaluated to determine their place in the diagnostic armamentarium. The first step involves determining the accuracy of the test, including the sensitivity and specificity, positive and negative predictive values, likelihood ratios for positive and negative tests, and receiver operating characteristic (ROC) curves. The role of the test in a diagnostic pathway has then to be determined, following which the effect on patient outcome should be examined.


Assuntos
Testes Diagnósticos de Rotina/métodos , Humanos , Funções Verossimilhança , Avaliação de Resultados da Assistência ao Paciente , Valor Preditivo dos Testes , Curva ROC
13.
Clin Biochem ; 83: 21-27, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32450078

RESUMO

OBJECTIVES: Measuring blood urea at the same time as serum creatinine in stable ambulatory patients in family practice is largely unnecessary. The objective was to assess the relative impact of changing the laboratory requisition versus audit and feedback and academic detailing on the volume of orders for blood urea. DESIGN AND METHODS: A natural experiment was observed over the period April 2015 to March 2018 in the Canadian province of Newfoundland where three health regions had different approaches to trying to reduce such urea testing. The Eastern and Western regions removed urea from the standard laboratory requisition but the test could still be ordered by writing it on the requisition. Central region requisitions continued to list urea. Audit and feedback was undertaken with family doctors in Eastern region after the requisition change and that was followed by academic detailing. A nephrologist gave presentations to groups of family doctors on one occasion in Central region. RESULTS: The volume of serum creatinine testing was largely unchanged over time in each region. The volume of urea testing reduced by 73%, 48% and 28% in Eastern, Western and central regions. Interrupted time series analysis showed significant changes in test volume after requisition change in Eastern and Western regions as well as after audit and feedback in Eastern and the presentations in Central region. The incremental impact of academic detailing was not statistically significant. CONCLUSION: We conclude that removing urea from standard test order menus was the most effective in reducing test volumes, but combination with audit and feedback augmented the impact.


Assuntos
Padrões de Prática Médica/estatística & dados numéricos , Procedimentos Desnecessários , Ureia/sangue , Análise Química do Sangue/estatística & dados numéricos , Creatinina/sangue , Educação Médica Continuada , Medicina de Família e Comunidade , Retroalimentação , Pesquisa sobre Serviços de Saúde , Humanos , Auditoria Médica , Terra Nova e Labrador , Avaliação de Processos e Resultados em Cuidados de Saúde , Procedimentos Desnecessários/estatística & dados numéricos
14.
Sci Rep ; 9(1): 7373, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31089166

RESUMO

Human-induced rapid environmental change (HIREC) has recently led to alterations in the fitness and behavior of many organisms. Game theory is an important tool of behavioral ecology for analyzing evolutionary situations involving multiple individuals. However, game theory bypasses the details by which behavioral phenotypes are determined, taking the functional perspective straight from expected payoffs to predicted frequencies of behaviors. In contrast with optimization approaches, we identify that to use existing game theoretic models to predict HIREC effects, additional mechanistic details (or assumptions) will often be required. We illustrate this in relation to the hawk-dove game by showing that three different mechanisms, each of which support the same ESS prior to HIREC (fixed polymorphism, probabilistic choice, or cue dependency), can have a substantial effect on behavior (and success) following HIREC. Surprisingly, an increase in the value of resources can lead to a reduction in payoffs (and vice versa), both in the immediate- and long-term following HIREC. An increase in expected costs also increases expected payoffs. Along with these counter-intuitive findings, this work shows that simply understanding the behavioral payoffs of existing games is insufficient to make predictions about the effects of HIREC.

15.
J Hum Evol ; 127: 81-92, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30777360

RESUMO

Long-term male-female bonds and bi-parental investment in offspring are hallmarks of human society. A key question is how these traits evolved from the polygynandrously mating multimale multifemale society that likely characterized the Pan-Homo ancestor. In all three species of savanna baboons, lactating females form strong ties (sometimes called "friendships") with one or more adult males. For yellow baboons (Papio cynocephalus) and chacma baboons (Papio ursinus), several lines of evidence suggest that these relationships are a form of male parenting effort. In olive baboons (Papio anubis), females are thought to preferentially mate with their "friends", and male-female bonds may thus function as a form of mating effort. Here, we draw on behavioral and genetic data to evaluate the factors that shape male-female relationships in a well-studied population of olive baboons. We find support for the parenting effort hypothesis in that sires have stronger bonds with their infants' mothers than do other males. These bonds sometimes persist past weaning age and, in many cases, the sire of the previous infant is still a close partner of the female when she nurses her subsequent offspring. We find that males who have the strongest bonds with females that have resumed cycling, but are not currently sexually receptive, are more likely to sire the female's next offspring but the estimate is associated with large statistical uncertainty. We also find that in over one third of the cases, a female's successive infants were sired by the same male. Thus, in olive baboons, the development of stable breeding bonds and paternal investment seem to be grounded in the formation of close ties between males and anestrous females. However, other factors such as male dominance rank also influence paternity success and may preclude stability of these bonds to the extent found in human societies.


Assuntos
Papio anubis/psicologia , Poder Familiar , Comportamento Sexual Animal , Animais , Feminino , Masculino
16.
Behav Processes ; 161: 129-138, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29369783

RESUMO

Cultural systems exhibit equifinal behavior - a single final state may be arrived at via different mechanisms and/or from different initial states. Potential for equifinality exists in all empirical studies of cultural transmission including controlled experiments, observational field research, and computational simulations. Acknowledging and anticipating the existence of equifinality is important in empirical studies of social learning and cultural evolution; it helps us understand the limitations of analytical approaches and can improve our ability to predict the dynamics of cultural transmission. Here, I illustrate and discuss examples of equifinality in studies of social learning, and how certain experimental designs might be prone to it. I then review examples of equifinality discussed in the social learning literature, namely the use of s-shaped diffusion curves to discern individual from social learning and operational definitions and analytical approaches used in studies of conformist transmission. While equifinality exists to some extent in all studies of social learning, I make suggestions for how to address instances of it, with an emphasis on using data simulation and methodological verification alongside modern statistical approaches that emphasize prediction and model comparison. In cases where evaluated learning mechanisms are equifinal due to non-methodological factors, I suggest that this is not always a problem if it helps us predict cultural change. In some cases, equifinal learning mechanisms might offer insight into how both individual learning, social learning strategies and other endogenous social factors might by important in structuring cultural dynamics and within- and between-group heterogeneity.


Assuntos
Evolução Cultural , Aprendizado Social , Humanos , Aprendizagem
17.
Ecol Evol ; 8(21): 10594-10607, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30464831

RESUMO

Adults sometimes disperse, while philopatric offspring inherit the natal site, a pattern known as bequeathal. Despite a decades-old empirical literature, little theoretical work has explored when natural selection may favor bequeathal. We present a simple mathematical model of the evolution of bequeathal in a stable environment, under both global and local dispersal. We find that natural selection favors bequeathal when adults are competitively advantaged over juveniles, baseline mortality is high, the environment is unsaturated, and when juveniles experience high dispersal mortality. However, frequently bequeathal may not evolve, because the fitness cost for the adult is too large relative to inclusive fitness benefits. Additionally, there are many situations for which bequeathal is an ESS, yet cannot invade the population. As bequeathal in real populations appears to be facultative, yet-to-be-modeled factors like timing of birth in the breeding season may strongly influence the patterns seen in natural populations.

18.
R Soc Open Sci ; 5(8): 181002, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30225086

RESUMO

Habitual reliance on tool use is a marked behavioural difference between wild robust (genus Sapajus) and gracile (genus Cebus) capuchin monkeys. Despite being well studied and having a rich repertoire of social and extractive foraging traditions, Cebus sp. rarely use tools and have never been observed using stone tools. By contrast, habitual tool use by Sapajus is widespread. We review theory and discuss factors which might explain these differences in patterns of tool use between Cebus and Sapajus. We then report the first case of habitual stone tool use in a gracile capuchin: a population of white-faced capuchins (Cebus capucinus imitator) in Coiba National Park, Panama who habitually rely on hammerstone and anvil tool use to access structurally protected food items in coastal areas including Terminalia catappa seeds, hermit crabs, marine snails, terrestrial crabs and other items. This behaviour has persisted on one island in Coiba National Park since at least 2004. From 1 year of camera trapping, we found that stone tool use is strongly male-biased. Of the 205 camera trap days where tool use was recorded, adult females were never observed to use stone tools, although they were frequently recorded at the sites and engaged in scrounging behaviour. Stone tool use occurs year-round in this population; over half of all identifiable individuals were observed participating. At the most active tool use site, 83.2% of days where capuchins were sighted corresponded with tool use. Capuchins inhabiting the Coiba archipelago are highly terrestrial, under decreased predation pressure and potentially experience resource limitation compared to mainland populations-three conditions considered important for the evolution of stone tool use. White-faced capuchin tool use in Coiba National Park thus offers unique opportunities to explore the ecological drivers and evolutionary underpinnings of stone tool use in a comparative within- and between-species context.

19.
Can J Kidney Health Dis ; 5: 2054358117749530, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29372064

RESUMO

PURPOSE OF REVIEW: This article serves to describe the Can-SOLVE CKD network, a program of research projects and infrastructure that has excited patients and given them hope that we can truly transform the care they receive. ISSUE: Chronic kidney disease (CKD) is a complex disorder that affects more than 4 million Canadians and costs the Canadian health care system more than $40 billion per year. The evidence base for guiding care in CKD is small, and even in areas where evidence exists, uptake of evidence into clinical practice has been slow. Compounding these complexities are the variations in outcomes for patients with CKD and difficulties predicting who is most likely to develop complications over time. Clearly these gaps in our knowledge and understanding of CKD need to be filled, but the current state of CKD research is not where it needs to be. A culture of clinical trials and inquiry into the disease is lacking, and much of the existing evidence base addresses the concerns of the researchers but not necessarily those of the patients. PROGRAM OVERVIEW: The Canadian Institutes of Health Research (CIHR) has launched the national Strategy for Patient-Oriented Research (SPOR), a coalition of federal, provincial, and territorial partners dedicated to integrating research into care. Canadians Seeking Solutions and Innovations to Overcome Chronic Kidney Disease (Can-SOLVE CKD) is one of five pan-Canadian chronic kidney disease networks supported through the SPOR. The vision of Can-SOLVE CKD is that by 2020 every Canadian with or at high risk for CKD will receive the best recommended care, experience optimal outcomes, and have the opportunity to participate in studies with novel therapies, regardless of age, sex, gender, location, or ethnicity. PROGRAM OBJECTIVE: The overarching objective of Can-SOLVE CKD is to accelerate the translation of knowledge about CKD into clinical research and practice. By focusing on the patient's voice and implementing relevant findings in real time, Can-SOLVE CKD will transform the care that CKD patients receive, and will improve kidney health for future generations.


OBJECTIF DE LA REVUE: Le présent article décrit le réseau Can-SOLVE CKD, un réseau basé sur un programme de projets et d'infrastructures de recherche qui ont soulevé l'enthousiasme des patients et qui nourrissent leur espoir de voir une réelle réforme des soins qu'ils reçoivent. CONTEXTE: L'insuffisance rénale chronique (IRC) est un trouble complexe qui affecte plus de quatre millions de Canadiens et qui engendre au système de santé canadien des coûts annuels de l'ordre de 40 milliards de dollars. Les données probantes sous-tendant les soins en IRC sont rares, et dans les branches où ces données existent, leur intégration à la pratique clinique se montre insuffisante. Ces problèmes sont aggravés d'abord par la grande variabilité du pronostic de la maladie, puis par la difficulté de prévoir quels patients seront les plus susceptibles de développer des complications. Ces lacunes de connaissances et de compréhension de l'IRC doivent manifestement être comblées; cependant, force est de constater que la recherche actuelle sur l'IRC est inadéquate. Outre l'absence d'une culture médicale qui encourage les essais cliniques, les données recueillies rejoignent les préoccupations des chercheurs sans nécessairement refléter celles des patients. PRÉSENTATION DU PROGRAMME: Lancée par l'Institut de recherche en santé du Canada (IRSC), la Stratégie de recherche axée sur le patient (SRAP) consiste en une coalition de partenaires fédéraux, provinciaux et territoriaux visant l'intégration des résultats de la recherche dans les soins prodigués aux patients. Le réseau Can-SOLVE CKD (Canadians Seeking Solutions and Innovations to Overcome Chronic Kidney Disease) est l'un des cinq réseaux de recherche pancanadiens sur les maladies chroniques soutenus par la SRAP. L'objectif du réseau Can-SOLVE CKD est tripartite : on souhaite que, d'ici 2020, tous les Canadiens atteints d'IRC (ou à haut risque de développer la maladie) 1- reçoivent les meilleurs soins; 2- obtiennent des résultats de santé optimaux; 3- aient l'occasion de participer à des études cliniques pertinentes (et ce, sans égard à leur âge, leur sexe, leur ethnicité ou leur lieu de résidence). OBJECTIF DU PROGRAMME: L'objectif principal du réseau Can-SOLVE CKD est d'accélérer l'application des connaissances sur l'IRC, tant en recherche qu'en pratique clinique. En s'intéressant aux préoccupations des patients et en appliquant en temps réel les résultats pertinents de la recherche, Can-SOLVE CKD transformera la façon dont seront soignés les patients atteints d'IRC et améliorera la santé rénale globale des générations futures.

20.
Proc Natl Acad Sci U S A ; 114(30): 7806-7813, 2017 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-28739946

RESUMO

An important extension to our understanding of evolutionary processes has been the discovery of the roles that individual and social learning play in creating recurring phenotypes on which selection can act. Cultural change occurs chiefly through invention of new behavioral variants combined with social transmission of the novel behaviors to new practitioners. Therefore, understanding what makes some individuals more likely to innovate and/or transmit new behaviors is critical for creating realistic models of culture change. The difficulty in identifying what behaviors qualify as new in wild animal populations has inhibited researchers from understanding the characteristics of behavioral innovations and innovators. Here, we present the findings of a long-term, systematic study of innovation (10 y, 10 groups, and 234 individuals) in wild capuchin monkeys (Cebus capucinus) in Lomas Barbudal, Costa Rica. Our methodology explicitly seeks novel behaviors, requiring their absence during the first 5 y of the study to qualify as novel in the second 5 y of the study. Only about 20% of 187 innovations identified were retained in innovators' individual behavioral repertoires, and 22% were subsequently seen in other group members. Older, more social monkeys were more likely to invent new forms of social interaction, whereas younger monkeys were more likely to innovate in other behavioral domains (foraging, investigative, and self-directed behaviors). Sex and rank had little effect on innovative tendencies. Relative to apes, capuchins devote more of their innovations repertoire to investigative behaviors and social bonding behaviors and less to foraging and comfort behaviors.

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