On the interplay among ambient temperature basal metabolic rate and body mass

One of the most generalized conclusions arising from studies analyzing the ecological variation of energy metabolism in endotherms is the apparent negative correlation between ambient temperature and mass-independent basal metabolic rate (residual BMR). As a consequence, ambient temperature has been considered the most important external factor driving the evolution of residual BMR. It is not clear, however, whether this relationship is size dependent, and artifacts such as the biased sampling of body masses in physiological data sets could cause us to overstate the ubiquity of the relationship. Accordingly, here we used published data on body mass (mb), BMR, and annual mean temperature (Tmean) for 458 mammal species (and/or subspecies) to examine the size dependence of the relationship between temperature and BMR. We found a significant interaction between mb and Tmean as predictors of residual BMR, such that the effect of Tmean on residual BMR decreases as a function of mb. In line with this, the amount of residual variance in BMR explained by Tmean decreased with increasing mb, from 20%–30% at body sizes of less than 100 g to almost 0 at body sizes greater than 1,000 g. These data suggest that our current understanding of the importance of broad-scale variation in ambient temperature as a driver of metabolic evolution in endotherms probably is affected by the large number of small species in both nature and physiological data sets

The effect of food availability on phenotypic plasticity and phenotypic integration in the hylid frog Hypsiboas pulchellus

Background: Changes in food availability usually have an effect on the fitness-related traits of anuran larvae, such as body shape, developmental rate, and body size. Organism: Hypsiboas pulchellus, the South American common tree frog. Aim: Analyse the effect of food availability on larval survival, developmental rate (Gosner stage at the end of the experiment), body size (body mass and total length), body shape (the ratio between body length and total length), and intestine size (gut dry mass and gut length). Methods: We exposed tadpoles of H. pulchellus, all from a single clutch, to different levels of food availability. We set up eight food availability groups of five individuals each. After 39 days, we measured all phenotypic variables studied. We used linear and logistic regressions to analyse the data. We also used a structural equation modelling approach to evaluate the likelihood of ten causal models of covariation among the phenotypic traits (derived from four major biological hypotheses). Results: Three traits were observed to vary positively with food availability: developmental stage, body size, and gut size. Tadpole survival did not change with food availability. The results of structural equation modelling indicate that: (1) food availability acts directly on body size and gut size, (2) body size directly affects developmental rate, and (3) developmental rate acts directly on body shape. Conclusions: The present study supports the idea that anuran larvae are strongly affected by food availability. It also illustrates how structural equation modelling can increase our understanding of phenotypic integration among several traits that respond to changes in food availability

Interações entre o mexilhão dourado e os macroinvertebrados bentônicos nativos do Rio Uruguai

The ecosystem effects of Limnoperna fortunei have been studied nationally in recent years. However, the interactions that this invader establishes with the native benthic fauna have not been determined in detail. The objective of this study was to collect information on the interactions between the golden mussel and macroinvertebrates native to the Uruguay River, through (a) bibliographic survey, (b) photographic record obtained in the field and (c) analysis of data from an experiment of colonization carried out previously on rocky shores of this river. The interactions reported in the bibliography mainly referred to direct interactions of L. fortunei biofouling on native bivalve and gastropod species, with a potential negative effect for these individuals. The photographic documentation specifically made it possible to report for the first time in the region, a direct interaction of L. fortunei with the Spongillidae family, through which these porifers cover and suffocate already settled mussels. Finally, through the experiment carried out in situ, it was found that the mussel generates indirect negative effects on some native benthic macroinvertebrates. According to the data analysis, a high abundance of settled mussels is related to a reduction in the abundances of two of the dominant native benthic groups of this river, such as gastropods and dipterans.Los efectos que Limnoperna fortunei ocasiona sobre los ecosistemas vienen siendo estudiados en los últimos años a nivel nacional. No obstante, las interacciones que este invasor establece con la fauna bentónica nativa no han sido determinadas en detalle. El objetivo de este estudio fue recopilar información sobre las interacciones entre el mejillón dorado y macroinvertebrados nativos del Río Uruguay, a través de (a) relevamiento bibliográfico, (b) registro fotográfico obtenido en campo y (c) análisis de datos de un experimento de colonización realizado previamente en litorales rocosos de este río. Las interacciones reportadas en la bibliografía refirieron mayoritariamente a interacciones directas de biofouling de L. fortunei sobre especies de bivalvos y gasterópodos nativos, con potencial efecto negativo para estos individuos. La documentación fotográfica permitió reportar, por primera vez en la región, una interacción directa de L. fortunei con la familia Spongillidae, mediante la cual estos poríferos cubren y sofocan a mejillones ya asentados. Finalmente, a través del experimento realizado in situ se encontró que el mejillón genera efectos negativos indirectos sobre algunos macroinvertebrados bentónicos nativos. Según el análisis de datos, una alta abundancia de mejillones asentados se relaciona con una reducción en las abundancias de dos de los grupos bentónicos nativos dominantes de este río, como son los gasterópodos y dípteros.Os efeitos que o Limnoperna fortunei causa nos ecossistemas foram estudados nos últimos anos em nível nacional. No entanto, as interações que este invasor estabelece com a fauna bentônica nativa não foram determinadas em detalhes. O objetivo deste estudo foi coletar informações sobre as interações entre o mexilhão dourado e macroinvertebrados nativos do Rio Uruguai, por meio de (a) levantamento bibliográfico, (b) registro fotográfico obtido em campo e (c) análise de dados de um experimento de colonização realizada anteriormente em costões rochosos deste rio. As interações relatadas na bibliografia referem-se principalmente às interações diretas de L. fortunei bioincrustantes em espécies nativas de bivalves e gastrópodes, com potencial efeito negativo para esses indivíduos. A documentação fotográfica especificamente possibilitou relatar, pela primeira vez na região, uma interação direta de L. fortunei com a família Spongillidae, através da qual esses poríferos cobrem e sufocam mexilhões já assentados. Por fim, por meio do experimento realizado in situ, constatou-se que o mexilhão gera efeitos negativos indiretos sobre alguns macroinvertebrados bentônicos nativos. De acordo com a análise dos dados, uma alta abundância de mexilhões assentados está relacionada a uma redução nas abundâncias de dois grupos bentônicos nativos dominantes deste rio, como gastrópodes e dípteros

Interacciones entre el mejillón dorado y macroinvertebrados bentónicos nativos del Río Uruguay

Los efectos que Limnoperna fortunei ocasiona sobre los ecosistemas vienen siendo estudiados en los últimos años a nivel nacional. No obstante, las interacciones que este invasor establece con la fauna bentónica nativa no han sido determinadas en detalle. El objetivo de este estudio fue recopilar información sobre las interacciones entre el mejillón dorado y macroinvertebrados nativos del Río Uruguay, a través de (a) relevamiento bibliográfico, (b) registro fotográfico obtenido en campo y (c) análisis de datos de un experimento de colonización realizado previamente en litorales rocosos de este río. Las interacciones reportadas en la bibliografía refirieron mayoritariamente a interacciones directas de biofouling de L. fortunei sobre especies de bivalvos y gasterópodos nativos, con potencial efecto negativo para estos individuos. La documentación fotográfica permitió reportar, por primera vez en la región, una interacción directa de L. fortunei con la familia Spongillidae, mediante la cual estos poríferos cubren y sofocan a mejillones ya asentados. Finalmente, a través del experimento realizado in situ se encontró que el mejillón genera efectos negativos indirectos sobre algunos macroinvertebrados bentónicos nativos. Según el análisis de datos, una alta abundancia de mejillones asentados se relaciona con una reducción en las abundancias de dos de los grupos bentónicos nativos dominantes de este río, como son los gasterópodos y dípteros

An Automatic Palindrome Generator

In 1984 Dan Hoey, a US naval mathematician, wrote a computer which he used to create a 540-word expansion of Leigh Mercer\u27s Panama palindrome (PD). It began A man, a plan, a caret, a ban, a myriad, a sum, a lac... and ended ...a calmus, a diaryman, a bater, a canal Panama. (For the full PD, plus additional information, see http://www2.vo.lu/homepages/phahn/anagrams/panama/htm.

Kinetics of Relativistic Runaway Electrons

Basal and maximum metabolic rates for rodent

Data from: Latitudinal patterns in rodent metabolic flexibility

Macrophysiology is defined as the study of variation in physiological traits--including physiological trait flexibility--over large geographical and temporal scales, and the ecological implications of this variation. A classic example of a macrophysiological trend is the one emerging from the climatic variability hypothesis (CVH), which states that as the range of climatic fluctuation experienced by terrestrial animals increases with latitude, individuals at higher latitudes should be more plastic than individuals inhabiting lower latitudes. In this context, we evaluate the correlation between absolute metabolic scope during cold exposure (an instantaneous measure of metabolic flexibility) and different geographic and climatic variables for 48 rodent species. Conventional and phylogenetic informed analyses indicated a positive correlation between metabolic scope and geographic latitude. These findings, together with previous reports on latitudinal pattern in phenotypic flexibility, suggest that an increase in physiological flexibility with latitude may be hold for many phenotypic traits

Data from: Latitudinal patterns in rodent metabolic flexibility

Macrophysiology is defined as the study of variation in physiological traits--including physiological trait flexibility--over large geographical and temporal scales, and the ecological implications of this variation. A classic example of a macrophysiological trend is the one emerging from the climatic variability hypothesis (CVH), which states that as the range of climatic fluctuation experienced by terrestrial animals increases with latitude, individuals at higher latitudes should be more plastic than individuals inhabiting lower latitudes. In this context, we evaluate the correlation between absolute metabolic scope during cold exposure (an instantaneous measure of metabolic flexibility) and different geographic and climatic variables for 48 rodent species. Conventional and phylogenetic informed analyses indicated a positive correlation between metabolic scope and geographic latitude. These findings, together with previous reports on latitudinal pattern in phenotypic flexibility, suggest that an increase in physiological flexibility with latitude may be hold for many phenotypic traits

Data from: Latitudinal patterns in rodent metabolic flexibility

Macrophysiology is defined as the study of variation in physiological traits--including physiological trait flexibility--over large geographical and temporal scales, and the ecological implications of this variation. A classic example of a macrophysiological trend is the one emerging from the climatic variability hypothesis (CVH), which states that as the range of climatic fluctuation experienced by terrestrial animals increases with latitude, individuals at higher latitudes should be more plastic than individuals inhabiting lower latitudes. In this context, we evaluate the correlation between absolute metabolic scope during cold exposure (an instantaneous measure of metabolic flexibility) and different geographic and climatic variables for 48 rodent species. Conventional and phylogenetic informed analyses indicated a positive correlation between metabolic scope and geographic latitude. These findings, together with previous reports on latitudinal pattern in phenotypic flexibility, suggest that an increase in physiological flexibility with latitude may be hold for many phenotypic traits

Naya_Dataset

Basal and maximum metabolic rates for rodent