Diversity dynamics in New Caledonia: towards the end of the museum model?

<p>Abstract</p> <p>Background</p> <p>The high diversity of New Caledonia has traditionally been seen as a result of its Gondwanan origin, old age and long isolation under stable climatic conditions (the museum model). Under this scenario, we would expect species diversification to follow a constant rate model. Alternatively, if New Caledonia was completely submerged after its breakup from Gondwana, as geological evidence indicates, we would expect species diversification to show a characteristic slowdown over time according to a diversity-dependent model where species accumulation decreases as space is filled.</p> <p>Results</p> <p>We reanalyze available datasets for New Caledonia and reconstruct the phylogenies using standardized methodologies; we use two ultrametrization alternatives; and we take into account phylogenetic uncertainty as well as incomplete taxon sampling when conducting diversification rate constancy tests. Our results indicate that for 8 of the 9 available phylogenies, there is significant evidence for a diversification slowdown. For the youngest group under investigation, the apparent lack of evidence of a significant slowdown could be because we are still observing the early phase of a logistic growth (i.e. the clade may be too young to exhibit a change in diversification rates).</p> <p>Conclusions</p> <p>Our results are consistent with a diversity-dependent model of diversification in New Caledonia. In opposition to the museum model, our results provide additional evidence that original New Caledonian biodiversity was wiped out during the episode of submersion, providing an open and empty space facilitating evolutionary radiations.</p

Evaluation of individual and ensemble probabilistic forecasts of COVID-19 mortality in the United States

Short-term probabilistic forecasts of the trajectory of the COVID-19 pandemic in the United States have served as a visible and important communication channel between the scientific modeling community and both the general public and decision-makers. Forecasting models provide specific, quantitative, and evaluable predictions that inform short-term decisions such as healthcare staffing needs, school closures, and allocation of medical supplies. Starting in April 2020, the US COVID-19 Forecast Hub (https://covid19forecasthub.org/) collected, disseminated, and synthesized tens of millions of specific predictions from more than 90 different academic, industry, and independent research groups. A multimodel ensemble forecast that combined predictions from dozens of groups every week provided the most consistently accurate probabilistic forecasts of incident deaths due to COVID-19 at the state and national level from April 2020 through October 2021. The performance of 27 individual models that submitted complete forecasts of COVID-19 deaths consistently throughout this year showed high variability in forecast skill across time, geospatial units, and forecast horizons. Two-thirds of the models evaluated showed better accuracy than a naïve baseline model. Forecast accuracy degraded as models made predictions further into the future, with probabilistic error at a 20-wk horizon three to five times larger than when predicting at a 1-wk horizon. This project underscores the role that collaboration and active coordination between governmental public-health agencies, academic modeling teams, and industry partners can play in developing modern modeling capabilities to support local, state, and federal response to outbreaks

Biomedical and ethnomedical practice in rural Zaire : Contrasts and complements

Some health care planners and scholars who work in developing countries have advocated the promotion of some form of cooperation, collaboration, or even integration of the medical services of biomedical practitioners with the services of local healers. This paper discusses issues that must be addressed in the consideration of such a possibility in a rural community in Zaire where the 'dual use' of medical resources is evident. After briefly outlining the characteristics of the biomedical and ethnomedical systems that now exist, the strengths and weaknesses of each system are evaluated and compared. In promoting cooperation between different types of practitioners, project planners, it is argued, should consider the strengths and weaknesses of each type of medical practice and should seek to improve the use of existing medical resources. The paper concludes by outlining a series of progressive stages of contact among practitioners that could lead to a system of mutual referral.

Symptoms and perceived severity of illness as predictive of treatment for diarrhea in six Asian and African sites

This paper examines associations between symptoms, judgment of severity and treatments given for episodes of childhood diarrhea. Using data from ten large sample surveys conducted in six research sites in Asia and Africa, the paper addresses three main questions. One, to what extent are judgments of severity of diarrhea among young children a function of the symptoms observed during an episode of diarrhea? Two, what is the relative importance of symptoms observed vs judgments of severity in the treatments given for diarrhea? And three, what do the results imply for programs promoting the use of ORT for diarrhea? The study found that mothers; perception of severity of illness is linked most closely to three symptoms: vomiting, fever and lassitude. These symptoms are associated with (a) treating the child at all and (b) taking the child to a health facility. These conclusions take on particular significance since they are based on a comparison of ten data sets from six sites differing widely in population density, ecology, access to medical services, educational level and financial resources.diarrhea ORT treatment

Webinar: Understanding the What, Where and Why the Practice of FGM/C continues

Population Council has successfully led the Evidence to End FGM/C: Research to Help Girls and Women Thrive consortium—a UKAID-funded research program to help end female genital mutilation/cutting (FGM/C) within one generation. The programme conducted high quality research across eight countries in Africa with significant country, regional and global relevance for the last five years 2015–2020. This is part two of a two-part webinar series intended for practitioners, researchers, donors and implementers and covering a range of evidence and implications on topics such as medicalization, laws, social norms, variations of the practice, and prospects for abandonment. Both webinars marked the end of a five-year program intended to expand the body of evidence on the most effective and cost-effective approaches to ending FGM/C in different contexts. This webinar, Understanding the What, Where and Why the Practice of FGM/C continues, aired live on May 22, 2020