SYSTEM FOR FIELD TESTING MECHANISMS OF EVOLUTION
Evolutionary biology has always faced a major hurdle -- how to test a process that takes place over thousands, if not millions, of years. Researchers at Stanford University in California may have come up with a solution, according to Nature. "Genetic mutations and the possible mechanisms underlying evolution have been studied in laboratory animals for decades," says David Kingsley, Ph.D., of Stanford's Howard Hughes Medical Institute. "The challenge has been to find a means of applying what scientists know to be true in the lab to systems in the natural world." Kingsley says that a small spiny fish called the three-spine stickleback, and the gene-linkage map of the fish's chromosomes that the team has developed, may be the tools evolutionary biologists have been needing. The key was to find two populations that unlike laboratory bred mice and rats, would have traits that had evolved naturally and yet could still be cross-bred. "What we needed were two species that had diverged fairly recently, had distinct morphological differences, were fast-growing and easy to keep in the laboratory," says Kingsley. The researchers intent was to develop a map of the inheritance patterns showing the links between genes from one generation to another.
CORNSTARCH EXPLAINS GIANT'S CAUSEWAY
Enormous columnar rock formations such as the Devil's Postpile in California have fascinated people for centuries. A pair of physicists, working on the cusp between physics and geology, have developed an explanation for these formations. Alberto G. Rojo, of the University of Michigan, and Eduardo A. Jagla, of the Centro Atómico Bariloche in Argentina, say that as lava cooled, fractures formed at the surface and moved downward. At the top, the fracture pattern looked like the familiar arrangement that appears in drying mud or in paint -- a random pattern of curved lines meeting at 90-degree angles. But as the fractures moved downward they began to take the path of least resistance. The configuration that minimizes the energy required to penetrate the interior turns out to be quasi-hexagonal -- a regular pattern of hexagons, pentagons, and heptagons, as in the Giant's Causeway. The results, published in the January issue of the American Physical Society journal, say the researchers support their theory with a computer model, along with a simple cornstarch experiment. "Many scientists believe that the cutting edge of physics exists only at the very small scale -- string theory, for example, or the very large -- cosmology and astrophysics," Rojo says. "I disagree. Many fundamental open questions and mysteries still remain at the scale of our everyday experience."
SIGNALS FROM RETINA LINKED TO BODY CLOCK
Harvard Medical School researchers have gained one of the first glimpses of how the body's circadian clock is linked to a tiny cluster of nerve cells behind the eyes that send out the signals that control natural daily rhythms. The newly discovered pathway, Science reports, could ultimately lead to new treatments for circadian disturbances such as certain sleep disorders. "If you could figure out the factors that are promoting wakefulness and sleep, that could in principle be turned into much better drugs for particular sleep disorders," says Chuck Weitz, professor of neurobiology. Circadian researchers have been successful in the past few years at identifying the molecular machinery, the genes and proteins, that make the circadian clock cells tick on a near 24-hour basis. But they were stymied when it came to figuring out how the machinery of these cells, located in the brain's suprachiasmatic nucleus, actually drives such daily rhythms as the rise and fall of body temperature and the sleep/wake cycle. "The reason this is exciting is that circadian rhythms, though controlled by the clock, can be influenced by the outside world, particularly light, transmitted through the retina," says Weitz.
SMART SPACESUIT IN DEVELOPMENT
Future astronauts will carry a small computer and video display in their space walk suits to replace the current radio systems, NASA reports. The space agency intends to fit the upgraded communications equipment into a space suit through a wearable computer. "The goal of WearSAT is to provide astronauts who are working outside the International Space Station on a space walk with visual information through a display, a wireless video terminal and a wearable computing system," says Steven Schwartz, project manager of WearSAT at the Massachusetts Institute of Technology, told the BBC program "Go Digital. "So that they can receive enhanced information while performing the task that they do on such space walks." A wireless network would allow controllers on the space station to beam complex information, such as schematics and technical diagrams, right into the astronaut's helmet. "What we're doing essentially is using the small amount of unused space within the suit to build a
body-conformable computer and provide it with a display system that does not require modifications to the current suit," says Chris Carr of MIT.
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