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Type 2 diabetes, one of the major causes of death and disability worldwide, is characterized by problems in the homeostasis of blood glucose. Current preventive policies focus mainly on individual behaviors (diet, exercise, salt and alcohol consumption). Recent hypotheses state that the higher incidence of metabolic disease in some human populations may be related to phenotypic decanalization causing a heightened phenotypic variance in response to unusual or stressful environmental conditions, although the nature of these conditions is under debate. Our aim was to explore variability patterns of fasting blood glucose to test phenotypic decanalization as a possible explanation of heightened prevalence for type 2 diabetes in some groups and to detect variables associated with its variance using a nation-wide survey of Argentinian adult population. We found patterns of higher local variance for fasting glycemia associated with lower income and educational attainment. We detected no meaningful association of glycemia or its variability with covariates related to individual behaviors (diet, physical activity, salt or alcohol consumption). Our results were consistent with the decanalization hypothesis for fasting glycemia, which appears associated to socioeconomic disadvantage. We therefore propose changes in public policy and discuss the implications for data gathering and further analyses.

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Taking Georges Canguilhem's 1943 book The normal and the pathological as a starting point, this article explores the ways in which the neurosciences define, validate, and legitimize the existence of autistic traits as a subclinical expression of autism. The general hypothesis is that different assumptions based on a naturalistic perspective of health and disease have become consolidated in the specialized literature. Such assumptions include that behaviors should be explained strictly in biological terms, that there is an objective and statistical parameter of normality, and that individuals' behaviors can be analyzed independently of their context. Based on some aspects of Canguilhem's arguments regarding health, normality, and normativity, we analyze the ways in which the neurosciences assign a quasi-pathological quality to the descriptive notion of autistic traits. It is possible to conclude that this process involves certain assumptions taken in an aprioristic and uncritical manner, which inhibits the discussion of key aspects associated with the nature of autism and that end up pathologizing differences between people.

A partir de la obra Lo normal y lo patológico de Georges Canguilhem, publicada en 1943, se explora cómo las neurociencias definen y legitiman, en la actualidad, la existencia de los rasgos autistas como expresión subclínica de autismo. La hipótesis general del presente trabajo es que en la bibliografía especializada de este ámbito parecen consolidarse diferentes supuestos asumidos en el marco de una perspectiva naturalista de la salud. Tales supuestos refieren a que los comportamientos deben ser explicados estrictamente en términos biológicos, que existe un parámetro de normalidad de carácter objetivo y estadístico, y que las conductas de los individuos pueden ser analizadas separadamente del contexto. Retomando algunos aspectos de la propuesta de Canguilhem sobre salud, normalidad y normatividad, se analiza de qué manera las neurociencias otorgan una cualidad cuasi-patológica a una noción descriptiva como la de rasgos autistas. A nuestro entender, este proceso involucra la asunción apriorística y acrítica de supuestos que impiden poner en discusión aspectos elementales asociados a la naturaleza del autismo y que conducen a patologizar la diferencia entre personas.

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RESUMEN A partir de la obra Lo normal y lo patológico de Georges Canguilhem, publicada en 1943, se explora cómo las neurociencias definen y legitiman, en la actualidad, la existencia de los rasgos autistas como expresión subclínica de autismo. La hipótesis general del presente trabajo es que en la bibliografía especializada de este ámbito parecen consolidarse diferentes supuestos asumidos en el marco de una perspectiva naturalista de la salud. Tales supuestos refieren a que los comportamientos deben ser explicados estrictamente en términos biológicos, que existe un parámetro de normalidad de carácter objetivo y estadístico, y que las conductas de los individuos pueden ser analizadas separadamente del contexto. Retomando algunos aspectos de la propuesta de Canguilhem sobre salud, normalidad y normatividad, se analiza de qué manera las neurociencias otorgan una cualidad cuasi-patológica a una noción descriptiva como la de rasgos autistas. A nuestro entender, este proceso involucra la asunción apriorística y acrítica de supuestos que impiden poner en discusión aspectos elementales asociados a la naturaleza del autismo y que conducen a patologizar la diferencia entre personas.

ABSTRACT Taking Georges Canguilhem's 1943 book The normal and the pathological as a starting point, this article explores the ways in which the neurosciences define, validate, and legitimize the existence of autistic traits as a subclinical expression of autism. The general hypothesis is that different assumptions based on a naturalistic perspective of health and disease have become consolidated in the specialized literature. Such assumptions include that behaviors should be explained strictly in biological terms, that there is an objective and statistical parameter of normality, and that individuals' behaviors can be analyzed independently of their context. Based on some aspects of Canguilhem's arguments regarding health, normality, and normativity, we analyze the ways in which the neurosciences assign a quasi-pathological quality to the descriptive notion of autistic traits. It is possible to conclude that this process involves certain assumptions taken in an aprioristic and uncritical manner, which inhibits the discussion of key aspects associated with the nature of autism and that end up pathologizing differences between people.

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Attention deficit hyperactivity disorder (ADHD) is considered to be the most frequent mental disorder in childhood. Although its diagnosis in the most utilized handbook of psychiatry in the world today - the Diagnostic and statistical handbook of mental disorders (DSM-5) - is based on behaviors of inattention, hyperactivity and impulsivity, numerous attempts to describe the biological bases of the disorder can be found, to be used for and also as risk markers. In this paper, we will critically analyze the validity of studies associated with the search for genetic markers of ADHD. First, a characterization of ADHD by the DSM-5 handbook is presented. Subsequently, the link between ADHD, risk factors and genetic markers is developed. Finally, some conclusions are presented which highlight simplifications and omissions that could have significant consequences.

El trastorno por déficit de atención e hiperactividad (TDAH) es el trastorno mental considerado más frecuente en la infancia. Si bien su diagnóstico en el manual de psiquiatría hoy más utilizado en el mundo, el Diagnostic and statistical manual of mental disorders (DSM-5), se basa en los comportamientos de desatención, hiperactividad e impulsividad, se encuentran numerosos intentos de describir las bases biológicas del trastorno para usarlos con fines de diagnóstico y como marcadores de riesgo. En este trabajo analizamos críticamente la validez de los estudios asociados a la búsqueda de marcadores genéticos para el TDAH. En primer lugar, se presenta la caracterización del TDAH en el manual DSM-5; luego, se desarrolla el vínculo entre el TDAH y los factores de riesgo y los marcadores genéticos; y, finalmente, se presentan algunas conclusiones en las que se señalan simplificaciones y omisiones que pueden tener consecuencias significativas.

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RESUMEN El trastorno por déficit de atención e hiperactividad (TDAH) es el trastorno mental considerado más frecuente en la infancia. Si bien su diagnóstico en el manual de psiquiatría hoy más utilizado en el mundo, el Diagnostic and statistical manual of mental disorders (DSM-5), se basa en los comportamientos de desatención, hiperactividad e impulsividad, se encuentran numerosos intentos de describir las bases biológicas del trastorno para usarlos con fines de diagnóstico y como marcadores de riesgo. En este trabajo analizamos críticamente la validez de los estudios asociados a la búsqueda de marcadores genéticos para el TDAH. En primer lugar, se presenta la caracterización del TDAH en el manual DSM-5; luego, se desarrolla el vínculo entre el TDAH y los factores de riesgo y los marcadores genéticos; y, finalmente, se presentan algunas conclusiones en las que se señalan simplificaciones y omisiones que pueden tener consecuencias significativas.

ABSTRACT: Attention deficit hyperactivity disorder (ADHD) is considered to be the most frequent mental disorder in childhood. Although its diagnosis in the most utilized handbook of psychiatry in the world today - the Diagnostic and statistical handbook of mental disorders (DSM-5) - is based on behaviors of inattention, hyperactivity and impulsivity, numerous attempts to describe the biological bases of the disorder can be found, to be used for and also as risk markers. In this paper, we will critically analyze the validity of studies associated with the search for genetic markers of ADHD. First, a characterization of ADHD by the DSM-5 handbook is presented. Subsequently, the link between ADHD, risk factors and genetic markers is developed. Finally, some conclusions are presented which highlight simplifications and omissions that could have significant consequences.

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Resumen El trastorno por déficit de atención e hiperactividad (TDAH) se encuentra entre los trastornos psiquiátricos infantiles más prevalentes en la actualidad y, desde áreas biomédicas y neurobiológicas, se considera que presenta una base biológica. En el presente trabajo se analizarán, desde una aproximación filosófica, los discursos que se despliegan desde dichas investigaciones con el objetivo de detectar y clarificar diversos aspectos fenoménicos, teóricos y ontológicos que le subyacen. En términos generales, hemos encontrado que la conceptualización del TDAH está atravesada por al menos cuatro niveles de organización diferentes: genético-molecular (genes y proteínas), tisular (partes del cerebro), órgano (cerebro como un todo) y el organísmico (individuo). Dichos niveles ocupan roles sumamente diferentes; ocupando los niveles inferiores de organización roles predominantes en lo explicativo así como presentando las entidades fundamentales en términos ontológicos. A su vez, el discurso neurocientífico presenta sesgos relacionados con la pérdida de consideración de la heterogeneidad, la omisión de los niveles superiores al organísmico y simplificaciones del ámbito genético-molecular y de la relación genotipo-fenotipo. Así, el tipo de indagación simplificante y que prepondera los niveles inferiores de la jerarquía biológica parece mostrar más dificultades que éxitos, y epistémicamente muestra grietas que no son saldadas.

Resumo O transtorno do déficit de atenção e hiperatividade (TDAH) encontra-se entre os transtornos psiquiátricos infantis mais prevalecentes na atualidade e considera-se, nas áreas biomédicas e neurobiológicas, que ele apresenta uma base biológica. No presente trabalho serão analisados, a partir de uma perspectiva filosófica, os discursos que se desdobram das pesquisas das áreas referidas, com o objetivo de detectar e esclarecer diversos aspectos fenomênicos, teóricos e ontológicos que lhes são subjacentes. Em termos gerais, encontramos que a conceitualização do TDAH está atravessada por pelo menos quatro níveis de organização diferentes: genético-molecular (genes e proteínas), tissular (partes do cérebro), órgão (cérebro como um todo) e o organismo (indivíduo). Esses níveis ocupam papéis sumamente diferentes, estando nos níveis inferiores de organização papéis predominantes no explicativo, assim como apresentam as entidades fundamentais em termos ontológicos. Por sua vez, o discurso neurocientífico contém um viés relacionado com a perda de consideração da heterogeneidade, a omissão dos níveis superiores ao organismo e simplificadores do âmbito genético-molecular e da relação genótipo-fenótipo. Assim, o tipo de indagação simplificadora e preponderante dos níveis inferiores da hierarquia biológica parece mostrar mais dificuldades que êxitos e epistemicamente mostra fissuras que não saldadas.

Abstract Attention deficit hyperactivity disorder (ADHD) is among the most prevalent psychiatric disorders in children at present and, from biomedical and neurobiological areas, it is considered to have a biological basis. In the present work we analyzed from a philosophical approach, the discourses deployed from these investigations in order to detect and clarify various phenomenal, theoretical and ontological aspects that underlie it. In general terms, we have found that the conceptualization of ADHD is traversed by at least four different organizational levels: genetic-molecular (genes and proteins), tissue (parts of the brain), organ (brain as a whole) and the organismic (individual). These levels occupy very different roles; lower levels of organization occupying predominant explanatory roles as well as presenting the fundamental entities in ontological terms. In turn, the neuroscientific discourse presents biases related to the loss of consideration of heterogeneity, the omission of levels superior to organismic and simplifications of the genetic-molecular domain and the genotype-phenotype relation. Thus, the type of simplifying inquiry in the lower levels of the biological hierarchy seems to show more difficulties than successes, and epistemically shows cracks that are not settled.

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Global climate change poses one of the greatest threats to species persistence. Most analyses of the potential biological impacts have focused on changes in mean temperature, but changes in thermal variance will also impact organisms and populations. We assessed the effects of acclimation to daily variance of temperature on dispersal and exploratory behavior in the terrestrial isopod Porcellio laevis in an open field. Acclimation treatments were 24 ± 0, 24 ± 4 and 24 ± 8 °C. Because the performance of ectotherms relates nonlinearly to temperature, we predicted that animals acclimated to a higher daily thermal variation should minimize the time exposed in the centre of open field, --i.e. increase the linearity of displacements. Consistent with our prediction, isopods acclimated to a thermally variable environment reduce their exploratory behaviour, hypothetically to minimize their exposure to adverse environmental conditions. This scenario as well as the long latency of animals after releases acclimated to variable environments is consistent with this idea. We suggested that to develop more realistic predictions about the biological impacts of climate change, one must consider the interactions between the mean and variance of environmental temperature on animals' performance.

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El presente trabajo tiene como objetivo analizar el ayer y el hoy del manejo de los restos humanos de comunidades aborígenes. Con este fin, se indagan los casos de tres museos argentinos que, a través de la historia, fueron adoptando distintas posturas y políticas respecto al tema: el Museo de Ciencias Naturales de La Plata, El Museo Ambrosetti, las Momias de Llullaillaco, así como las normativas legales y éticas concernientes al tema. El objetivo último del trabajo es llamar a la reflexión sobre temas como la restitución, la repatriación de restos humanos y el reconocimiento de los derechos de los pueblos originarios.

This paper analyzes previous and current practices in handling human remains from aboriginal communities. The cases of three Argentinian museums are analyzed which adopted different practices throughout history: Natural Sciences Museum of La Plata, the Ambrosetti Museum, the Llullaillaco mummies, along with ethical and legal norms. The ultimate goal of the work is to draw attention to topics such as restitution, repatriation and the recognition of the rights of aboriginal peoples.

O presente trabalho tem por objetivo analisar o ontem e o hoje do manejo dos restos humanos de comunidades arborígenes. Com esta finalidade, são questionados os casos de três museus argentinos que através da história foram adotando distintas posturas e políticas a respeito do tema: o Museu de Ciências Naturais da Plata, o Museu Ambrosetti, as Múmias de Llullaillaco, assim como as normas legais e éticas concernentes ao tema. O objetivo último do trabalho é chamar a reflexão sobre temas como a restituição, a repatriação de restos humanos e o reconhecimento dos direitos dos povos originários.

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This article focuses on the relationship between microevolution and macroevolution. The main purpose is to argue that up to the present time in the consolidation of the evolutionary synthesis macroevolution has been always conceived as dependent on microevolution. Such dependence was very clear in the synthesis, but seems to have been left aside by later authors. Nevertheless, we show that the criticisms of the synthesis since the decade of the 1970s did not modify that general trend: the new perspectives reproduced the dependence of macroevolution on microevolution by means of strategies different than those appealed to by the traditional synthesis.

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Global climate change is one of the greatest threats to biodiversity; one of the most important effects is the increase in the mean earth surface temperature. However, another but poorly studied main characteristic of global change appears to be an increase in temperature variability. Most of the current analyses of global change have focused on mean values, paying less attention to the role of the fluctuations of environmental variables. We experimentally tested the effects of environmental temperature variability on characteristics associated to the fitness (body mass balance, growth rate, and survival), metabolic rate (VCO(2)) and molecular traits (heat shock protein expression, Hsp70), in an ectotherm, the terrestrial woodlouse Porcellio laevis. Our general hypotheses are that higher values of thermal amplitude may directly affect life-history traits, increasing metabolic cost and stress responses. At first, results supported our hypotheses showing a diversity of responses among characters to the experimental thermal treatments. We emphasize that knowledge about the cellular and physiological mechanisms by which animals cope with environmental changes is essential to understand the impact of mean climatic change and variability. Also, we consider that the studies that only incorporate only mean temperatures to predict the life-history, ecological and evolutionary impact of global temperature changes present important problems to predict the diversity of responses of the organism. This is because the analysis ignores the complexity and details of the molecular and physiological processes by which animals cope with environmental variability, as well as the life-history and demographic consequences of such variability.

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Different hypotheses attempt to explain how different stages of organisms with complex life cycles respond to environmental changes. Most studies have focused at the among-species level showing similar responses to temperature throughout ontogeny. However, there is no agreement about the pattern expected at the intraspecific scale where a strong selective effect is expected. In this paper, we studied the effects of thermal treatments on a life history trait (developmental rate) and a physiological trait (metabolic rate) during development in the fruitfly Drosophila buzzatii. First, we estimated the rate of development during larval life (LDR) and the pupal stage (PDR) in flies derived from two natural populations exposed to several thermal treatments. Our results showed that the developmental rate ratio, LDR/PDR, did not vary between populations, and that the effects of thermal treatments were stage specific. Second, we studied the relationship between developmental rate (DR) and metabolic rate (MR) in each life cycle stage. We found that allometric relationships between DR and MR varied throughout ontogeny, a pattern that shed light on the mechanisms responsible for thermal plasticity. We conclude that, although different populations may show developmental rate isomorphy; larvae and pupae may choose alternative "decisions" in terms of life-history evolution and physiological traits when confronted to different thermal environments.

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BACKGROUND: Previously, we have shown there is clinal variation for egg-to-adult developmental time along geographic gradients in Drosophila melanogaster. Further, we also have identified mutations in genes involved in metabolic and neurogenic pathways that affect development time (heterochronic genes). However, we do not know whether these loci affect variation in developmental time in natural populations. METHODOLOGY/PRINCIPAL FINDINGS: Here, we constructed second chromosome substitution lines from natural populations of Drosophila melanogaster from an altitudinal cline, and measured egg-adult development time for each line. We found not only a large amount of genetic variation for developmental time, but also positive associations of the development time with thermal amplitude and altitude. We performed genetic complementation tests using substitution lines with the longest and shortest developmental times and heterochronic mutations. We identified segregating variation for neurogenic and metabolic genes that largely affected the duration of the larval stages but had no impact on the timing of metamorphosis. CONCLUSIONS/SIGNIFICANCE: Altitudinal clinal variation in developmental time for natural chromosome substitution lines provides a unique opportunity to dissect the response of heterochronic genes to environmental gradients. Ontogenetic stage-specific variation in invected, mastermind, cricklet and CG14591 may affect natural variation in development time and thermal evolution.

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Global climate change is one of the greatest threats to biodiversity; one of the most important effects is increase in the mean earth surface temperature. However, another but poorly studied main effect of global change appears to be an increase in temperature variability. Most of the current analyses of global change have focused on mean values, paying less attention to the role of the fluctuations of environmental variables. We tested the effects of daily thermal amplitude with constant mean (24-24 degrees C, 27-21 degrees C and 32-16 degrees C) on different performance traits (rollover speed, body mass balance and survival) in populations of woodlouse (Porcellio laevis) from two altitudes. We observed that maximum performance showed a significant effect of population in the first but not in the fifth week, and only the population effect was significant for optimum temperature. Interestingly, populations under higher amplitude in environmental temperature exhibited higher resistance to a fluctuating climatic regime. We suggest that our results indicate that thermal variability may produce important effects on biodiversity. Therefore, in order to develop more realistic scenarios of global climate change effects on biodiversity, the effects of thermal variability as well as mean need to be examined simultaneously.

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We assessed the indirect response of longevity in lines selected for wing length (WL) and developmental time (DT). Longevity in selection lines was compared to laboratory control lines and the offspring of recently collected females. Wild flies (W lines), flies from lines selected for fast development (F lines), and for fast development and large wing length (L lines) outlived control laboratory lines (C lines) and lines selected for fast development and short wing (S lines). The decline in longevity in S lines is in line with the idea that body size and longevity are correlated and may be the result of the fixation of alleles at loci affecting pleiotropically the two traits under selection and longevity. In addition, inbreeding and artificial selection affected the correlation between wing length and longevity that occurs in natural populations of Drosophila buzzatii, suggesting that correlations between traits are not a perdurable feature in a population.

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