An emerging central concept in evolutionary biology suggests that symbiosis is a universal characteristic of living organisms that can help in understanding complex traits and phenotypes. During evolution, an integrative circuitry fundamental for survival has been established between commensal gut microbiota and host. On the basis of recent knowledge in worms, flies, and humans, an important role of the gut microbiota in aging and longevity is emerging.
Secular growth has been occurring in Europe for about 150 years. In the USA, since 1900, each new generation has increased by an average of 1in (2.54cm) in height and about 10lb (4.54kg) in weight. This trend has generally been viewed as favorable and tallness is admired, with the current ideal height for a man in the Western world being 6ft 2in (188cm). The Japanese have increased in height since the end of the Second World War by about 5in (12.7cm) in height and the Chinese have been growing at the rate of 2.54cm/decade since the 1950s.
This article argues that dietary restriction would not increase longevity in species able to leave a place where they are subjected to starvation. Human beings can emigrate when feeding conditions are a threat to survival and thus they would not live longer if subjected to dietary restriction.
Some animals live in environments in which the food supply fluctuates. When it is scarce these animals do not breed, but invest resources into survival until food is again available, and they can reproduce. Under these circumstances the lifespan can be increased, just as it is after calorie restriction. Other animals have a fairly constant food supply, and it is predicted that these would not have an extended life span if subjected to calorie restriction. Hibernation is a natural form of calorie restriction, and in some cases may lengthen lifespan.
Evolutionary medicine acknowledges that many chronic degenerative diseases result from conflicts between our rapidly changing environment, our dietary habits included, and our genome, which has remained virtually unchanged since the Palaeolithic era. Reconstruction of the diet before the Agricultural and Industrial Revolutions is therefore indicated, but hampered by the ongoing debate on our ancestors' ecological niche.
An invasive population of Burmese pythons (Python molurus bivittatus) is established across several thousand square kilometers of southern Florida and appears to have caused precipitous population declines among several species of native mammals. Why has this giant snake had such great success as an invasive species when many established reptiles have failed to spread?
Few time series of deep-sea systems exist from which the factors affecting abyssal fish populations can be evaluated. Previous analysis showed an increase in grenadier abundance, in the eastern North Pacific, which lagged epibenthic megafaunal abundance, mostly echinoderms, by 9-20 months. Subsequent diet studies suggested that carrion is the grenadier's most important food. Our goal was to evaluate if changes in carrion supply might drive the temporal changes in grenadier abundance.
A time-resolved record of inhabited water depth, metabolic rate and trophic behaviour of the orange roughy Hoplostethus atlanticus was recovered from combined stable-isotope analyses of otolith and muscle tissue. The results demonstrate that H. atlanticus from the north-east Atlantic Ocean have a complex life history with three distinct depth-stratified life stages. Early juvenile H. atlanticus occupy relatively shallow habitats, juvenile H. atlanticus show a deep-demersal phase, rising at sexual maturity, and adult H. atlanticus exploit increasingly deep habitats with increasing age.
The "One World One Health Initiative" has attended little to the priorities, concepts and practices of resource-poor communities confronting disease and the implications of these concerns for its biomedical, ecological and institutional approach to disease surveillance and control. Using the example of Buruli ulcer (BU) and its bacterial etiology, Mycobacterium ulcerans, in south-central Cameroon, we build on debates about the contributions of "local knowledge" and "alternative models" to biomedical knowledge of disease transmission.
Risk Analysis: An Official Publication of the Society for Risk Analysis
A mail survey on ecological risk perception was administered in the summer of 2002 to a randomized sample of the lay public and to selected risk professionals at the U.S. Environmental Protection Agency (US EPA). The ranking of 24 ecological risk items, from global climate change to commercial fishing, reveals that the lay public is more concerned about low-probability, high-consequence risks whereas the risk professionals are more concerned about risks that pose long-term, ecosystem-level impacts.