University of California, Irvine researchers have identified the chemical switch that triggers the genetic mechanism regulating our internal body clock. The finding, which uncovers the most specific information about the body’s circadian rhythms to date, identifies a precise target for new pharmaceuticals that can treat sleep disorders and a host of related ailments. Paolo Sassone-Corsi, Distinguished Professor and Chair of Pharmacology, found that a single amino acid activates the genes that regulate circadian rhythms. Amino acids are the building blocks of proteins, and Sassone-Corsi was surprised to find that only a single amino acid activates the body-clock mechanism because of the complex genes involved.
When humans began to migrate out of Africa about 100,000 years ago, their skin color gradually changed to adapt to their new environments. And when the last Ice Age ended about 10,000 years ago, marine ancestors of ocean-dwelling stickleback fish experienced dramatic changes in skin coloring as they colonized newly formed lakes and streams. New research shows that despite the vast evolutionary gulf between humans and the three-spined stickleback fish, the two species have adopted a common genetic strategy to acquire the skin pigmentation that would help each species thrive in their new environments.
The transition from apes to humans may have been partially triggered by the need to stand on two legs, in order to safely carry heavier babies. This theory of species evolution presented by Lia Amaral from the University of São Paulo in Brazil has just been published online in Springer’s journal, Naturwissenschaften.
A tiny possum and a giant rat were recorded by scientists as probable new species on a recent expedition to Indonesia’s remote and virtually unknown “Lost World” in the pristine wilderness of western New Guinea’s Foja Mountains. The Foja Wilderness is part of the great Mamberamo Basin, the largest unroaded tropical forest in the Asia Pacific region.
Neuroecology bridges a critical gap between studying the neural basis of behavior (neuroethology) and evaluating the consequences of that behavior at the ecological levels of populations and communities. A plant laces its leaves with a noxious chemical, forcing a hungry herbivore to choose between starving, eating a potentially toxic item, or moving on. A newt secretes a potent neurotoxin to defend against predators, unwittingly setting off a cascade of effects in its freshwater pond, where other inhabitants co-opt the toxin for different uses. A squid escapes a predator by clouding the water with ink — but is this a visual defense, or are there chemical implications for the ecosystem as well?
Growth hormone treatments work better on some children than on others, but judging which candidates will gain those vital inches in height is no simple task. Now researchers have developed a new mathematical model which predicts the optimal dose of growth hormone to treat children who are abnormally short for a wide range of reasons. A new study describes a model that can be more widely applied than previous versions, with greater predictive accuracy.