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Few things seem so silly as a peacock preening its gaudy tail or an elk clanking through the trees with its cumbersome antlers or even a male human displaying his hairy chest, but now we know that these secondary sexual characteristics have evolved because they attract mates, and in the animal kingdom, procreation leads to better odds of survival. These days, the study of evolution has shifted from the question of why such male traits exist to what makes them work and where they came from. In Thursday's edition of the science journal Cell, a team lead by world-renowned University...

DINOSAURS were running out of evolutionary steam during their last 50 million years on Earth, scientists have learned. The reptiles were left behind in the "Cretaceous Terrestrial Revolution", 100 million years ago, that saw the massive proliferation of vegetation and many animals. While flowering plants, lizards, snakes, birds and mammals all evolved swiftly, dinosaurs plodded behind. A short time later, they were extinct. Researchers made the discovery after using computer programs to produce a "super-tree" of dinosaur lineages. The results showed the most likely pattern of evolution for 440 of the 600 known species of dinosaur. The findings, published in...

Some bacterial cells can swim, morph into new forms and even become dangerously virulent - all without initial involvement of DNA. Yale University researchers describe July 18 in the journal Science how bacteria accomplish this amazing feat - and in doing so provide a glimpse of what the earliest forms of life on Earth may have looked like.

"From 1970 to 2000, there was a widespread view that although natural selection is very important, it is relatively rare," said Jonathan Pritchard, a geneticist at the University of Chicago. "That view was driven largely because we did not have data to identify the signals of natural selection. . . . In the last five years or so, there has been a tremendous growth in our understanding of how much selection there is."

Our inability to produce a chemical present in every other primate may be linked to a series of chronic diseases. Roger Highfield explains more What does it mean to be human? For most people, it all comes down to that extraordinary object between our ears, and how it blesses us with language, laughter and logic. But not for Ajit Varki, a doctor-cum-scientist who works in California. Not so rare: a molecule absorbed by eating red meat has been linked to inflammation and auto-immune illnesses Not so rare: a molecule absorbed by eating red meat has been linked to inflammation and...

Everyone is born with one, but no one knows what it’s for. The human appendix is a small dead-end tube connected to the cecum, or ascending colon, one section of the large intestine. Everyone lives happily with it until it becomes painfully inflamed, when the only treatment is to remove it surgically. Then everyone lives happily without it. So why is it there in the first place? Some experts have guessed that it is a vestige of the evolutionary development of some other organ, but there is little evidence for an appendix in our evolutionary ancestors. Few mammals have any...