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Adaptive mutation is common in E. coli, say IU researchersThe quickening of genetic mutation rates in bacteria may not only happen when the microorganisms find themselves in strange and stressful circumstances. A new report in Molecular Microbiology by Indiana University Bloomington researchers shows that at least one bacterium, Escherichia coli, ratchets up its "adaptive mutation" machinery when it simply runs out of food.Biologists Patricia Foster and Jill Layton found that as E. coli cells begin to starve, the bacteria quadruple their expression of DNA Polymerase IV (Pol IV), a mutation-causing enzyme that is notoriously bad at copying DNA accurately. The...

Ground-breaking work in understanding of time Mechanics, Zeno and Hawking undergo revision A bold paper which has highly impressed some of the world's top physicists and been published in the August issue of Foundations of Physics Letters, seems set to change the way we think about the nature of time and its relationship to motion and classical and quantum mechanics. Much to the science world's astonishment, the work also appears to provide solutions to Zeno of Elea's famous motion paradoxes, almost 2500 years after they were originally conceived by the ancient Greek philosopher. In doing so, its unlikely author, who...

Evolutionary 'fast-track,' in which the hunted outwit their hunters, could explain why human diseases progress so rapidly, Cornell biologists reportIn the fishbowl of life, when hordes of well-fed predators drive their prey to the brink of extinction, sometimes evolution takes the fast track to help the hunted survive -- and then thrive to outnumber their predators. This rapid evolution, predicted by Cornell University biologists in computer models and demonstrated with Pac-Man-like creatures and their algae food in laboratory habitats called chemostats, could play an important role in the ecological dynamics of many predator-prey systems, according to an article in the...

Artificial Life Experiments Show How Complex Functions Can Evolve Arlington, Va.—If the evolution of complex organisms were a road trip, then the simple country drives are what get you there. And sometimes even potholes along the way are important.An interdisciplinary team of scientists at Michigan State University and the California Institute of Technology, with the help of powerful computers, has used a kind of artificial life, or ALife, to create a road map detailing the evolution of complex organisms, an old problem in biology.In an article in the May 8 issue of the international journal Nature, Richard Lenski, Charles Ofria,...

Lessons learned Right-wing America has already lost the war, writes Mohamed El-Sayed Said, but humanity has yet to win it In a number of ways, the war in Iraq is over. The ultra-right coalition in the United States has effectively lost the battle. The evolution of the military conflict in Iraq will have diminishing significance as compared with the political struggles arising from the conflict, particularly within the United States. The omens predicting the political defeat and potential break- down of the right-wing coalition currently in power in the United States are many. The most crucial sign of political defeat...

For more than a decade, researchers have been trying to create accurate computer models of Escherichia coli (E. coli), a bacterium that makes headlines for its varied roles in food poisoning, drug manufacture and biological research.By combining laboratory data with recently completed genetic databases, researchers can craft digital colonies of organisms that mimic, and even predict, some behaviors of living cells to an accuracy of about 75 percent. Now, NSF-supported researchers at the University of California at San Diego have created a computer model that accurately predicts how E. coli metabolic systems adapt and evolve when the bacteria are placed...

The AAAS Board recently passed a resolution urging policymakers to oppose teaching "Intelligent Design Theory" within science classrooms, but rather, to keep it separate, in the same way that creationism and other religious teachings are currently handled."The United States has promised that no child will be left behind in the classroom," said Alan I. Leshner, CEO and executive publisher for AAAS. "If intelligent design theory is presented within science courses as factually based, it is likely to confuse American schoolchildren and to undermine the integrity of U.S. science education."American society supports and encourages a broad range of viewpoints, Leshner noted....

Functional MRI scans have revealed a "biologically embedded" basis for altruistic behavior, with several characteristic regions of the brain being activated when players of a game called "Prisoner's Dilemma" decide to trust each other and cooperate, rather than betray each other for immediate gain, say researchers from Emory University. They report on their study in the July 18 issue of the journal Neuron, published by Cell Press. For many years, evolutionary biologists, behaviorists, economists and political scientists have attempted to understand why cooperation exists between human beings, even though that cooperation may not result in a direct or immediate reward....

Scientists have assembled the first synthetic virus. The US researchers built the infectious agent from scratch using the genome sequence for polio. Read More...

In 1971, a Soviet biological weapons test caused an outbreak of smallpox in a nearby town, and three deaths. The accident, confirmed for the first time, suggests the current smallpox vaccine would work against the smallpox used in Soviet weapons, the type thought most likely to have fallen into terrorist hands.The report was presented on Saturday to a US government committee advising on whether authorities should offer smallpox vaccinations to the public amid growing fears of bioterrorism. Their decision is expected this week.Smallpox has been extinct in the wild since 1980. In 1959, universal vaccination had driven it from...

CHAMPAIGN, Ill. — Life did not begin with one primordial cell. Instead, there were initially at least three simple types of loosely constructed cellular organizations. They swam in a pool of genes, evolving in a communal way that aided one another in bootstrapping into the three distinct types of cells by sharing their evolutionary inventions. The driving force in evolving cellular life on Earth, says Carl Woese, a microbiologist at the University of Illinois at Urbana-Champaign, has been horizontal gene transfer, in which the acquisition of alien cellular components, including genes and proteins, work to promote the evolution of...

There are two things about the Daniel Pearl video that are unforgettably shocking. The first, of course, is the sight of his murder. Even as he looks into the camera and utters the statements that his captors demand that he utter--a confession of his Jewishness, followed by a confession of the sins of America--there is a good, genial look in his eyes, and a complete lack of despair in his voice; and then suddenly he is on the floor and a knife is passed along his throat and his severed head is raised by a hand in a white sleeve,...

CAMBRIDGE, Mass. May 3 (UPI) -- A Russian physicist at MIT -- the Massachusetts Institute of Technology -- has announced experimental data that may topple one of science's most cherished dogmas -- that Newton's constant of gravitation, famously symbolized by a large "G," remains constant wherever, whenever and however it is measured. "My colleagues and I have successfully experimentally demonstrated that the force of gravitation between two test bodies varies with their orientation in space, relative to a system of distant stars," Mikhail Gershteyn, a visiting scientist at the MIT Plasma Science and Fusion Center, told United Press International from...

A mouse-sized fossil from 125 million years ago is the earliest known member of the mammal group that includes humans, say researchers. The animal is a primitive example of today's dominant mammals. "It's at the very root of this diverse and incredibly important group," says palaeontologist Zhe-Xi Luo of the Carnegie Museum of Natural History in Pittsburgh1. The mammal, Eomaia scansoria, might have scampered up a tree as a feathered dinosaur ran past. The animal's elongated digits suggest that it was adept at climbing; its name translates as 'dawn-mother climber'.*Article Plus Photo Here*

A team of international researchers from Germany, the Netherlands and San Diego may have shed light on why chimps and humans are so genetically similar (nearly 99 percent of shared DNA sequences), and yet so mentally different. In a study published in the April 12, 2002 issue of the journal Science, the scientists noted that the striking difference between these primate cousins is most evident in their brains. The disparity appears to be the result of evolutionary differences in gene and protein expression, the manner in which coded information in genes is activated in the brain, then converted into proteins...

Was Australopithecus ancestral to humans? Were they merely cousins in the evolutionary chain? Or simply a stage between apes and humans? Among various debates about these early hominids is the argument whether or not they could stand and walk upright like people do. William Sanders, a paleontologist at the University of Michigan, has found that Australopithecus shared many, but not all, of the anatomical features that enable humans to walk upright. He will present his findings April 3 at the Geological Society of America's North-Central Section and Southeastern Section Joint Meeting in Lexington, Kentucky. "It turns out that in mammals,...

Rare fossilized tube feet suggest functional shift through time CHAMPAIGN, Ill. — Fleshy tube feet preserved in a rare fossil suggest an ecological shift through time, and may settle a long-standing debate about the preservation of soft parts, say paleontologists at the University of Illinois.Discovered in the Hunsrueck Slate of Germany by an amateur collector, the specimen is a brittle star, Bundenbachia beneckei, of the phylum Echinodermata, which includes starfishes and sea urchins. In life, the tube feet were fleshy extensions of an internal plumbing system called the water vascular system, and projected from the animal like so many small...

Progressively larger brains evolved in primates of all stripes, not just humans. We can thank a common capacity for solving a broad range of problems, from coordinating social alliances to inventing tools, according to a new study. This conclusion challenges a popular theory that big, smart brains arose primarily because they afforded advantages when it came to negotiating complex social situations during human evolution. "The ability to learn from others, invent new behaviors, and use tools may have [also] played pivotal roles in primate-brain evolution," say Simon M. Reader of McGill University in Montreal and Kevin N. Laland of the...

Human and fly studies tally good and bad mutations,stress ongoing role of natural selection Researchers from the University of Chicago have demonstrated that natural selection plays a much larger role in molecular evolution than anyone suspected. Their report, published in the February 28 issue of Nature, shows that about 25 percent of genes are evolving rapidly in response to competitive pressures. A second paper in the same issue confirms this discovery. Although these papers focus on fruit flies, a previous report from the Chicago authors found a similar role for positive and negative selection on the human genome. Data ...

MOLECULE THAT RESTRICTS MOUSE CELLS’ POTENCY COULD YIELD EMBRYONIC STEM CELLS WITHOUT THE SACRIFICE OF EMBRYOS PHILADELPHIA ­ Scientists at the University of Pennsylvania have identified a receptor that plays a key role in restricting embryonic stem cells’ pluripotency, their ability to develop into virtually any of an adult animal’s cell types. The work is the first demonstration of a mechanism by which pluripotency is lost in mammalian embryos, one that operates with nearly the precision of an on/off switch in mouse embryos. With further study, the receptor, dubbed GCNF, could open the door to new ways of creating ...