Word: braining
(lookup in dictionary)
(lookup stats)
Dates: all
Sort By: most recent first
(reverse)
...paleontologists have accumulated more and more fossils, they have compiled data on a long list of anatomical features, including body shape, bipedalism, brain size, the shape of the skull and face, the size of canine teeth, and opposable thumbs. Using comparative analyses of these attributes, along with dating that shows when various features appeared or vanished, they have constructed increasingly elaborate family trees that show the relationships between apes, ancient hominids and us. Along the way they learned, among other things, that Darwin, even with next to no actual data, was close to being right in his intuition that apes...
...human populations the researchers tested--but not in seven species of nonhuman primates, including chimps--the researchers suggest that lack of MYH16 made it possible for our ancestors to evolve smaller jaw muscles some 2 million years ago. That loss in muscle strength, they say, allowed the braincase and brain to grow larger. It's a controversial claim, one disputed by anthropologist C. Owen Lovejoy of Kent State University. "Brains don't expand because they were permitted to do so," he says. "They expand because they were selected"--because they conferred extra reproductive success on their owners, perhaps by allowing...
...apelike origins appeared in Science last month. A research team led by James Sikela of the University of Colorado at Denver and Health Sciences Center, in Aurora, Colo., looked at a gene that is believed to code for a piece of protein, called DUF1220, found in areas of the brain associated with higher cognitive function. The gene comes in multiple copies in a wide range of primates--but, the scientists found, humans carry the most copies. African great apes have substantially fewer copies, and the number found in more distant kin--orangutans and Old World monkeys--drops off even more...
Another discovery, first published online by Nature two months ago, describes a gene that appears to play a role in human brain development. A team led by biostatistician Katherine Pollard, now at the University of California, Davis, and Sofie Salama, of U.C. Santa Cruz, used a sophisticated computer program to search the genomes of humans, chimps and other vertebrates for segments that have undergone changes at substantially accelerated rates. They eventually homed in on 49 discrete areas they dubbed human accelerated regions, or HARS...
...region that changed most dramatically from chimps to humans, known as HAR1, turns out to be part of a gene that is active in fetal brain tissue only between the seventh and 19th weeks of gestation. Although the gene's precise function is unknown, that happens to be the period when a protein called reelin helps the human cerebral cortex develop its characteristic six-layer structure. What makes the team's research especially intriguing is that all but two of the HARs lie in those enigmatic functional noncoding regions of the genome, supporting the idea that much of the difference...