A Blog Around The Clock

There are 10 new articles in PLoS ONE today. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week - you go and look for your own favourites:

Imitation of Body Movements Facilitated by Joint Attention through Eye Contact and Pointing in Japanese Monkey:

Eye contact and pointing are typical gestures in order to direct another individual's attention toward a target. We previously investigated on Japanese monkeys whether joint attention ability encouraged by eye contact and pointing was associated with the imitation of human's actions. The monkeys with the joint attention skills showed the imitation of human's actions. In the current study, we investigated on a monkey whether joint attention ability also facilitated the imitation of human body-movements. Results showed that the monkey being taught eye contact and pointing showed the imitation of human body-movements. These results suggest that the monkeys have basic potential for following another individual's motion, and that what imitation expresses depends on where the monkeys are paying attention. Thus, eye contact and pointing are suitable for directing the monkey's attention toward the human.

Converting Endangered Species Categories to Probabilities of Extinction for Phylogenetic Conservation Prioritization:

Categories of imperilment like the global IUCN Red List have been transformed to probabilities of extinction and used to rank species by the amount of imperiled evolutionary history they represent (e.g. by the Edge of Existence programme). We investigate the stability of such lists when ranks are converted to probabilities of extinction under different scenarios. Using a simple example and computer simulation, we show that preserving the categories when converting such list designations to probabilities of extinction does not guarantee the stability of the resulting lists. Care must be taken when choosing a suitable transformation, especially if conservation dollars are allocated to species in a ranked fashion. We advocate routine sensitivity analyses.

Food Inequality Negatively Impacts Cardiac Health in Rabbits:

Individuals with lower socioeconomic status experience higher rates of mortality and are more likely to suffer from numerous diseases. While some studies indicate that humans who suffer from social inequality suffer generally worse health, to our knowledge no controlled experiments of this nature have been done in any species. Lipofuscin is a highly oxidized cross-linked aggregate consisting of oxidized protein and lipid clusters. This eminent terminal oxidation outcome accumulates within cells during aging process. Thirty two rabbits were assigned into four groups randomly of eight each. The first group encountered food deprivation for eight weeks and was kept in an isolated situation. The second group was food deprived for eight weeks but encountered to other groups continuously. The third group suffered two weeks of deprivation and then received free access to food. The fourth group had free access to diet without any deprivation. All hearts were removed for histopathological evaluation. Cross-sections of hearts were examined by light microscopy for the presence of yellow-brown Lipofuscin pigment granules. Here we show that relative food deprivation can cause accumulation of Lipofuscin pigmentation. We find that cardiac Lipofuscin deposition increases the most in the inequitable condition in which food deprived individuals observe well-fed individuals. Our findings demonstrate that a sense of inequality in food intake can promote aging more than food deprivation alone. These findings should be considered as a basis for further studies on the physiological mechanisms by which inequality negatively impacts health and well-being.