Panzee doesn’t talk, but she knows a word when she hears one — even if it’s emitted by a computer with a synthetic speech impediment. That’s not too shabby for a chimpanzee. Raised to recognize 128 spoken words by pointing to corresponding symbols, Panzee perceives acoustically distorted words about as well as people do, say psychology graduate student Lisa Heimbauer of Georgia State University in Atlanta and her colleagues. Panzee thus challenges the argument that only people can recognize highly distorted words, thanks to brains tuned to speech sounds. Read the full story.
Archive for Biology
Chimp Recognizes Human Words
Alzheimer’s Has a Genetic Component
The high-risk version of a gene associated with Alzheimer’s disease hinders the brain’s ability to clear out a troublesome protein, a new study finds. Researchers have known that people who carry the e4 version of the gene APOE are at higher risk for Alzheimer’s disease and more likely to have cell-killing plaques in their brains than people who have the e3 or e2 versions. But it hasn’t been clear whether people with the e4 version made more of the plaque protein — called amyloid-beta — or if the stuff just stuck around in their brains longer. Read the full story.
Nobel Scientist Calls for Population Control
A 93-year-old Nobel laureate in physiology or medicine received a standing ovation from hundreds of scientists June 30 at the end of a speech in which he urged the world’s young people to take measures to control runaway population growth in order to resolve related ills that have resulted from humans’ remarkable evolutionary success as a species.
Gene Therapy May Offer Hope for Genetic Diseases
A new type of gene therapy allows scientists to fix DNA defects directly. That’s a potentially revolutionary improvement on present gene therapy techniques, which introduce working genes to cells — but not into the genetic library itself. Working with newborn mice, researchers led by Katherine High at the Children’s Hospital of Philadelphia found that molecular editors called zinc finger nucleases can correct a genetic mutation that leads to the blood-clotting disorder hemophilia. Fixing a mistake in the gene for blood coagulation factor IX allowed the animals to make about 3 percent to 7 percent of normal levels of the protein, High and her colleagues report online June 26 in Nature. Even such modest increases are therapeutically meaningful, High says. People who make about 5 percent of normal levels of the clotting factor have mild cases of hemophilia. Read the full story.
Global Diabetes Rates Climb
Diabetes incidence has been climbing precipitously in the developed world along with rises in obesity rates and dietary and other lifestyle changes. But a massive new study finds that the rest of the global population has not been immune to these changes. Globally, the rate of diabetes has more than doubled in the past three decades. Read the full story.
Oceans Appear to Be in Trouble
Most people know that wild fisheries are dwindling, and we might know that low-oxygen aquatic dead zones are blooming around the planet’s most crowded coasts. But the oceans appear to be undergoing fundamental changes — many of them for the worse — that we can barely understand, in part because we barely understand that vast blue territory that covers 70% of the globe. That’s the conclusion of a surprising new report issued by the International Programme on the State of the Ocean (IPSO), a global panel of marine experts that met this year at Oxford University to examine the latest science on ocean health. That health, they found, is not good. According to the authors, we are “at high risk for entering a phase of extinction of marine species unprecedented in human history.” It’s not just about overfishing or marine pollution or even climate change. It’s all of those destructive factors working cumulatively and occurring much more rapidly than scientists had expected. “The findings are shocking,” says Alex Rogers, the scientific director of IPSO. “We are looking at consequences for humankind that will impact in our lifetime, and worse, our children’s and generations beyond that.” Read the full story.
Sleep is Important to Learning and Memory
Sleep’s function has long been a mystery, but many researchers have gathered evidence that it is important for learning and memory. Two new studies confirm that sleep plays a central role in solidifying memories and preparing the brain for new learning. Tickling a few neurons located at the top of the fruit fly brain triggers the insects to sleep, researchers led by Paul Shaw at Washington University in St. Louis discovered. Turning on the sleep-initiating brain cells makes short-term memories into long-lived ones, the researchers report June 24 in Science. A separate study in the same issue of Science, by researchers at the University of Wisconsin–Madison, describes microscopic evidence that during sleep, connections between brain cells are pruned.
Snakes Give Clue to Human Biology
Snakes have been around for some 150 million years, but their ancient physiology might hold some important clues to developing new drugs. Aside from their sleek exteriors, snakes’ internal physiology is perhaps even more intriguing. “It’s a really fun model for studying the extremes of adaptation,” Todd Castoe, a researcher at the University of Colorado (CU) School of Medicine’s biochemistry and molecular genetics department, said June 20 at the Evolution 2011 annual conference in Norman, Okla. In addition to the wow-factor of deciphering the snakes’ interesting innards, the strange systems could help us better understand our own biology. Read the full story.
Brain Training Boosts IQ
Could a simple memory workout make you smarter? An intriguing new study by researchers at the University of Michigan suggests it can — a finding that adds a wrinkle to the prevailing notion that IQ is largely fixed by genes. The study involved 62 elementary- and middle-school children from southeast Michigan who were randomly assigned to train on one of two video game-like computer tasks. One group performed a mental-training exercise aimed at improving working memory, the ability to hold and retrieve information in the short term. The other group practiced general knowledge and vocabulary skills. Both groups trained for one month, five times a week for 15 minutes per session. Read the full story.
Human Mutation Rate Slower than Thought
The first direct measurements of human mutation rates reveal that the speed at which successive generations accumulate single-letter genetic changes is much slower than previously thought. The study, published online June 12 in Nature Genetics, also shows that some individuals mutate faster than others. That means it may be fairly common for people to inherit a disproportionate share of mutations from one parent. Read the full story.