Ancient protein dating back 80 million years to the Cretaceous geologic period has been preserved in bone fragments and soft tissues of a hadrosaur, or duck-billed dinosaur, according to a study in the May 1 issue of Science. Led by scientists at Beth Israel Deaconess Medical Center (BIDMC) and North Carolina State University (NCSU), the new findings support earlier results from analyses suggesting that collagen protein survived in the bones of a well preserved Tyrannosaurus rex, and offer robust new evidence supporting previous conclusions that birds and dinosaurs are evolutionarily related. In April 2007 John Asara, PhD, Director of the Mass Spectrometry Core at BIDMC, together with NCSU paleontologist Mary Schweitzer, PhD, published two papers in Science describing their discovery that collagen extracted from bone fragments of a 68-million-year-old T. rex closely matched the amino acid sequences of modern day chickens. Not surprisingly, the widely publicized findings created a great deal of controversy.
Scientists studying the DNA of Neanderthals say they can find no evidence that this ancient species ever interbred with modern humans. But our evolutionary cousins may well have been able to speak as well as us, said Prof Svante Paabo from Germany's Max Planck Institute.
The researchers, led by Associate Professor Ana Maria Cuervo, blocked the ageing process in mice livers by stopping the build-up of harmful proteins inside the organ's cells. As people age their cells become less efficient at getting rid of damaged protein resulting in a build-up of toxic material that is especially pronounced in Alzheimer's, Parkinson's and other neurodegenerative disorders. The researchers say the findings suggest that therapies for boosting protein clearance might help stave off some of the declines in function that accompanies old age.
Scientists are talking for the first time about the old idea of resurrecting extinct species as if this staple of science fiction is a realistic possibility, saying that a living mammoth could perhaps be regenerated for as little as $10 million. A woolly mammoth hair ball. Hairs like these were used to sequence the mammoth genome. The same technology could be applied to any other extinct species from which one can obtain hair, horn, hooves, fur or feathers, and which went extinct within the last 60,000 years, the effective age limit for DNA.
For millennia, humans and viruses have been locked in an evolutionary back-and-forth -- one changes to outsmart the other, prompting the second to change and outsmart the first. With retroviruses, which work by inserting themselves into their host's DNA, the evidence remains in our genes.
A number of states have been considering laws that, under the guise of "academic freedom," single out evolution for special criticism. Most of them haven't made it out of the state legislatures, and one that did was promptly vetoed. But the last of these bills under consideration, the Louisiana Science Education Act (LSEA), was enacted by the signature of Governor Bobby Jindal yesterday.
Translate abstract goals into a form your ancestral systems -- which traffic largely in dumb reflexes -- can understand: if-then. If you find yourself in a particular situation, then take a specific action.
Talk about a long silence – no one has heard their voices for 30,000 years. Now the long-extinct Neanderthals are speaking up – or at least a computer synthesiser is doing so on their behalf.
Their results show that the genomes of modern humans and Neanderthals are at least 99.5-percent identical, but despite this genetic similarity, and despite the two species having cohabitated the same geographic region for thousands of years, there is ...
