982 research outputs found

    A formal test of linguistic and genetic coevolution in native Central and South America

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    This paper investigates a mechanism of linguistic and genetic coevolution in Native Central and South America. This mechanism proposes that a process of population fissions, expansions into new territories, and isolation of ancestral and descendant groups will produce congruent language and gene trees. To evaluate this population fissions mechanism, we collected published mtDNA sequences for 1,381 individuals from 17 Native Central and South American populations. We then tested the hypothesis that three well-known language classifications also represented the genetic structure of these populations. We rejected the hypothesis for each language classification. Our tests revealed linguistic and genetic correspondence in several shallow branches common to each classification, but no linguistic and genetic correspondence in the deeper branches contained in two of the language classifications. We discuss the possible causes for the lack of congruence between linguistic and genetic structure in the region, and describe alternative mechanisms of linguistic and genetic correspondence and their predictions. Am J Phys Anthropol, 2007. © 2007 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/55923/1/20542_ftp.pd

    Algunos comentarios acerca de la enseñanza de la historia de Colombia

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    El presente artículo de ninguna manera pretende agotar el tema que se aborta. El objetivo fundamental es: mostrar que la enseñanza de la Historia de Colombia ha sido tratada en forma poco científica y que no se le ha dado la importancia que en realidad merece. Además, destacar la labor que desarrollan nuevos investigadores al presentar un nuevo enfoque de la enseñanza y de la investigación histérica

    Parent Perception of Their Child’s Asthma Control and Concurrent Complementary and Alternative Medicine Use

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    We conducted a cross-sectional survey of 1322 parents of children with asthma to measure the prevalence and factors associated with complementary and alternative medicine (CAM) use for pediatric asthma. Multivariate regression techniques were used to determine factors associated with CAM use. Eleven percent (141/1322) of children were given CAM. Parents of children on daily medications who were perceived to have poor asthma control were almost three times more likely to use CAM than parents of children on no daily medications who were perceived to have high asthma control (risk ratio: = 2.81; confidence interval: 1.72, 4.60); age, gender, race, income, and education level were not significant independent predictors. Parent perception of asthma control is significantly associated with CAM use. It is important for providers to elicit information regarding CAM use in the clinic, as this may imply that the asthma symptoms may not be well controlled.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/63130/1/pai.2008.0503.pd

    Exploiting a readily available but hard to digest resource: A review of exudativorous mammals identified thus far and how they cope in captivity

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    Gum is a widely available carbohydrate, composed mainly of non-digestible structural carbohydrates. No mammalian enzymes can digest gum, therefore a mammal ingesting gum must rely on microbial fermentation in order to access the energy it possesses. Gums are known as relatively nutrient poor. Despite this, some mammals have evolved to exploit this food resource. We aim to review the literature for all mammal species which have been recorded to ingest gum, whether quantified or not and discuss this in context of their evolutionary adaptations. We also investigated the recommended captive diets for these species to look at if gum is recommended. We conducted a literature search on ISI Web of Knowledge to tabulate all mammal species observed ingesting gum and classify them as obligate, facultative or opportunistic feeders. We encountered 94 mammal species which eat gum in the wild (26 obligate feeders, 35 facultative feeders and 33 opportunistic feeders). Obligate feeders have entirely evolved to exploit this resource but were found to not be given gum in captivity, which may explain why they are failing to thrive, as opposed to facultative feeders which have fewer issues. Gum may be necessary for the health of obligate feeders in captivity. Future research should focus on the physiological effects that gum ingestion poses on different digestive systems

    Trialling nutrient recommendations for slow lorises (Nycticebus spp.) based on wild feeding ecology

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    Slow loris (Nycticebus spp.) captive diets have been based on routine and anecdotes rather than scientific fact. The growing body of evidence contradicts the high fruit diet supported by such anecdotes. Non-human primate nutrient requirements are grouped into new (based on the common marmoset Callithrix jacchus) or old world (based on rhesus macaques Macaca mulatta) primates. Slow lorises are known to suffer from many health ailments in captivity such as dental disease, obesity, wasting and kidney issues all of which have been linked to diet. This study aimed to estimate nutrient intake from free-ranging slow lorises and to determine whether this intake can be used as nutrient recommendations. We collected data of nutrient intake, food passage rate and digestibility of captive slow lorises on three diet treatments 1: current captive type diet which is mostly fruits, 2: wild-type diet made only of food items from their natural diet, 3: new diet made to reflect wild slow loris nutrient intake. In order to validate our nutrient recommendations, diets 2 and 3 would have to be significantly different to Diet 1 in terms of nutrients, but not different from each other. Captive diets were significantly higher in soluble carbohydrates and lower in minerals and fibre fractions than both diets 2 and 3. Diets 2 and 3 led to a significantly increased food passage time and to more effective fibre and calcium digestion compared to Diet 1. We also observed obese individuals lost weight and underweight individuals gained weight. Our nutrient recommendations have been validated by our trials, and new or old world monkey nutrient recommendations are not consistent with our results. Diets should be high in protein and fibre and low in soluble carbohydrates and fats
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