"Everyone has assumed we age by rust. But how do you explain animals that don't age? Some tortoises lay eggs at the age of 100, there are whales that live to be 200 and clams that make it past 400 years."
Stuart Kim, PhD, Stanford University professor of developmental biology and genetics
A prevailing theory of aging has been challenged by Stanford University Medical School researchers. Their discovery contradicts the theory that aging is a buildup of tissue damage similar to rust. The Stanford findings suggest specific genetic instructions drive the process. If they are right, science might one day find ways of switching the signals off and halting or even reversing aging.
Continue reading "Is Aging an Accident of Evolution? - (A Weekend Feature)" »
In a real-life accident straight out of Indiana Jones, a young boy trips and falls while chasing his trusted dog Tau through high grass somewhere in remote South Africa and stumbles over the fossil remains an ancient boy -a new hominid species that lived two million years ago. The remains have been classified as Australopithecus sediba, a new species of early man that’s likely a descendant of Australopithecus africanus. Geologists estimated that the individuals lived 1.78 to 1.95 million years ago, probably closer to the older date, a period when australopithecines and early species of Homo were contemporaries.
Continue reading "How Google Earth Led to the Discovery of a New Species of Early Man" »
Scientists say a third hominin group may have co-existed with early Homo sapiens and Neanderthals. A DNA sample taken from an ancient pinky bone that belonged to a child who died between 48,000 and 30,000 years ago, suggests that a previously unknown group of human ancestors intermingled with Neanderthals and modern humans.
Continue reading ""X-Woman" Discovered -Shared Ancestry with Neanderthals and Modern Humans" »
Now, after some three billion years, the Darwinian era is over. The epoch of species competition came to an end about 10 thousand years ago when a single species, Homo sapiens, began to dominate and reorganize the planet. Since that time, cultural evolution has replaced biological evolution as the driving force of change.
Freeman Dyson -Institute for Advanced Study
Continue reading "Has Human Culture Replaced Biological Evolution? (A Galaxy Classic)" »
Recent research shows that Neanderthals didn't talk like us. Shocking, we know, but this isn't the uber-obvious statement it might initially appear. Because it's not about languages, or how discussing daily bison hunts might be more exciting than last night's "Lost" - it's about a fundamental difference in the fundamental noises they could make.
Continue reading "Was Neanderthal's Speech Different Than Modern Humans? Experts Say "Yes, Very"" »
The pressures of human evolution could explain the apparent rise of disorders such as autoimmune diseases and autism, researchers say. Some adaptations may even help such ailments persist. Previous work in evolutionary medicine helped explain why disease is so prevalent and difficult to prevent. Because natural selection favors reproduction over health, biology evolves more slowly than culture, and pathogens evolve more quickly than humans.
Continue reading " Evolution May Trigger Rise of Human Disorders and Disease -New Research" »
Everything you need to know about the evolution debate in a single sentence: while one side shouts about how it hasn't happened, the scientists have already measured its speed. It turns out that when you're interested in things like "proof" and "inquiry" you can make forward progress instead of insisting everything ever was already known before the invention of the lightbulb.
An international collaboration between the Max Planck Institute and Indiana University analyzed the mutations of thirty mustard samples over five years. The painstaking research was intended to identify every change at every step, instead of the usual "Come back at the end and see what happened." They found an evolutionary speed of one base pair mutation per 140 million base pairs per generation. Each plant has 120 million, and when you add up how many millions of each plant there are and how fast they grow that's a breakneck genetic speed.
Continue reading "Hyper Speed: Mutation Rate of Evolution Discovered" »
Although It has taken homo sapiens several
million years to evolve from the apes, the useful information in our
DNA, has probably changed by only a few million bits. So the rate of
biological evolution in humans, Stephen Hawking points out in his Life in the Universe lecture, is about a bit a year.
Continue reading "Stephen Hawking: "The Human Species Has Entered a New Stage of Evolution" - The Daily Galaxy Top Story of 2009" »
Scientists have shown that evolution has built-in one-way gates, mutational processes which ensure that the benefits of millions of years aren't undone by accident.
Evolution takes an unimaginably long time - so long that opponents refuse to believe it's possible, or that even the amount of time is possible. Progress is incredibly slow as random tiny mutations are screened over millions of years to discover which work best. Backsliding would be even worse - the only thing worse than using a hundred million years to optimize a regulatory protein would be accidentally undoing the work over the next hundred kilo-millenia. Now University of Oregon investigators have discovered a genetic ratchet which prevents such extremely anti-productive reversals.
Continue reading "Evolution's Genetic-Mutation Process Discovered" »