'Thirst for knowledge' may be opium craving
...ctivity, Biederman's research shows, parallels the decline in the pleasure felt during repeated viewing. "One advantage of competitive learning is that the inhibited neurons are now free to code for other stimulus patterns," Biederman writes. This preference for novel concepts also has evolutionary value, he...Global patterns of geographic range sizes: A bird's eye view
...itudes. Nearly 70 years later, this north-to-south decline in range size was codified as Rapoport's rule -- but not without generating considerable debate about the universality of the principle. The question has remained controversial largely because it has been explored mostly at limited scales, with studi...Eavesdropping fringe-lipped bats spread culture through sound
...h their ability to learn socially. As frog species decline and change in tropical areas, the fringe-lipped bats' social learning skills could be an advantage. "This study has interesting conservation implications," said Page. "For a predator that is specialized to feed on a group of animals facing catastroph...New egg freezing technique offers hope to hundreds of women
...en men and women, whereby women's supplies of eggs decline at a faster rate than men's supplies of sperm." Dr Chamayou, scientific director of the Unita di Medicina Della Riproduzione, Fondazione HERA, Catania, Italy, told the conference that Italy had banned embryo and zygote freezing in 2004, and any embr...Teenage and 60-year-old mums are consequences of evolution
...se or shortly after. "Therefore, the accelerated decline in fertility, rather than the menopause itself, is... 150 years, the postmenopausal state and the prior decline in fertility was positively useful. Living through the menopause and beyond is not a part of our nat...Long-term study shows brain function not impaired by tight diabetes control and hypoglycemia
... tighter, control -- were associated with a modest decline in motor speed and psychomotor efficiency, but no other cognitive domain was affected. "This is very good news for patients with type 1 diabetes," says Dr. Jacobson. "Severe hypoglycemia can still be a very dangerous condition. But with proper educa...Coral death results from bacteria fed by algae
...efs, setting the stage for the long-term continued decline of coral. Reporting in the June 5 on-line ve...ositive feedback loop that accelerates the rate of decline in already damaged reef ecosystems." The report describes the other conditions that put coral reefs...Recent, rapid climate change is driving evolution of animal species
...les and smaller population sizes will experience a decline in population size or be replaced by more southern species." "Consequently, genetic shifts in the timing of seasonal events should precede genetic shifts of thermal optima or increased heat tolerance over evolutionary time," said Holzapfel. "That is...Study shows that genetic quality of sperm deteriorates as men age
...bility gradually worsens with age, as sperm counts decline and the sperm lose motility and their ability to swim in a straight line. In the current study, the researchers analyzed DNA damage, chromosomal abnormalities and gene mutations in semen samples from the same subjects 97 healthy, non-smoking LLNL e...Acid rain causing decline in sugar maples, say researchers
...es "the most conclusive evidence to date" that the decline of sugar maples is linked to the effects of acid rain produced by human activity, said Timothy Fahey, professor of forest ecology at Cornell and co-author of the study, which is published in the May issue of Ecology. Juice wrote the main part of the ...Children born after abortion ban had 'significantly better' educational achievements
...n in the United States contributed to a subsequent decline in crime rates. However, in a thought-provoking new article from the Journal of Political Economy--co-edited by Levitt--Cristian Pop-Eleches (Columbia University) presents a case in which children born just after an abortion ban display "significantl...Alarming decline in Nepal's rhinos and tigers in former Maoist stronghold
... Nepal's premier national parks reveal an alarming decline in tiger and rhino populations, indicating widespr...eam found evidence of just three. This significant decline is due to poachers who took advantage of the absence of antipoaching patrols in this critical rhino ...Ancient Etruscans unlikely ancestors of modern Tuscans, statistical testing reveals
... look into what might have been the causes of this decline in the population. It may have been quite abrupt. Mostly, it's a matter of guessing.'' According to Mountain, the field of anthropological genetics is replete with such educated guesses. ''There's so much storytelling that goes on in our field where ...Live via satellite: Scientists to track Caspian Sea sturgeons
...cent times, with estimates suggesting a 90 percent decline over the last two decades. The Ural River is home to the last great population of the beluga and is the only place where beluga reproduces naturally and unhindered by dams. Preserving this population is vital to ensuring natural replenishment of Cas...Gene expression becomes heterogeneous with age in humans and rats
...-standing observation concerning the physiological decline that accompanies aging is its variability--some people age better than others. However, there has thus far been little or no evidence supporting the existence of similar heterogeneity at the level of gene expression. Lack of such evidence, in turn, g...JCI table of contents, May 18, 2006
...tudinal PET studies, the authors saw a significant decline in pancreatic uptake of DTBZ that preceded the loss of glycemic control in the diabetic rat. These studies suggest that PET-based quantitation of VMAT2 receptors could provide a non-invasive measurement of beta cell mass that could be used to study t...Global warming may have damaged coral reefs forever
...utterfly fish and two damsel fish), although their decline probably started to happen soon after 1998. The survey also revealed that species diversity of the fish community had decreased by 50 per cent in the heavily impacted sites. Reduced biodiversity results in a more fragile and less stable ecosystem. ...Studies shed new light on why exercise can protect against skin and bowel cancers
...health of the non-exercising mice was beginning to decline due to higher numbers of polyps. There were higher levels of hormones known to be associated with the onset of cancer insulin-like growth factor-1 (IGF-1) and corticosterone amongst the exercising mice, but this did not correlate with higher total ...Nature vs Nintendo: Video games or national parks
...les were highly significantly correlated with this decline in national park visitation," said Pergams. "Multi...ll as oil prices, is so highly correlated with the decline in national park visits that there is likely to be some association." Pergams ruled out variables su...... yet recovered, Shapiro said. Shapiro compared the decline of the butterflies to similar declines in populations of frogs and other amphibians. While there may be different possible explanations for declines at each location, "the pattern is regional," he said. Shapiro is working to test various ideas about ...