By LES LINE In a rite of spring nearly as old as the Nebraska sandhills, greater prairie chickens and sharp-tailed grouse gather before dawn on their respective dancing grounds at Valentine National Wildlife Refuge in the north-central part of the state. While females watch, the males lower their heads, raise their tails, spread their wings, inflate colorful air sacs on their necks and stamp their feet while making hollow cooing or moaning sounds. The basic purpose of this elaborate display is to attract a mate. Indeed, the dancing ground, or lek, is the avian equivalent of a singles bar, said Dr. Robert Gibson, a behavioral ecologist and professor of biological sciences at the University of Nebraska. But Dr. Gibson, who has studied lekking behavior around the world, is convinced there is more going on. Copyright 2003 The New York Times Company

Keyword: Sexual Behavior
Link ID: 3748 - Posted: 04.29.2003

Migratory birds not only get to see the world. A new study finds that these globetrotters also have better long-term memories than stay-at-home relatives. The extra brain power could help ensure that the birds don’t get lost on their travels. Birds flying long distances use celestial cues, their sense of smell, and Earth’s magnetic field as rough guides to navigation. As they near their final destination, however, they switch strategies. They look for landmarks such as bushes and trees they have memorized during previous trips. That's how the birds return to the same breeding, wintering, and stopover sites year after year. Anatomical studies suggested that migrants do a lot of learning en route. Garden warblers, for example, return to central Europe from their first trip to Africa with a bigger hippocampus, a region of the brain involved in learning spatial information. Nonmigrating Sardinian warblers, on the other hand, show no such change. But direct evidence that life on the move makes birds remember better was missing. Copyright © 2003 by the American Association for the Advancement of Science.

Keyword: Animal Migration; Learning & Memory
Link ID: 3747 - Posted: 06.24.2010

Preliminary genome comparison points to primate individuality. HELEN PEARSON By studying chimpanzees, scientists are honing their genetic view of humanity, researchers told this week's meeting of the Human Genome Organisation in Cancun, Mexico. A group presented the first detailed comparison between a large chunk of human DNA and the equivalent from our closest relative. The genetic make-up of chimpanzee chromosome 22 is hot off the press, having just been sequenced, and matches human chromosome 21. The data call for some revision of the estimated genetic similarity between us and our closest relatives. Previously, human and chimp genetic sequences were quoted as being nearly 99% identical, with a difference of only a few DNA's letters. In fact, the similarity may be as low as 94-95%, says Todd Taylor of the RIKEN Genomic Sciences Center in Yokohama, Japan. © Nature News Service / Macmillan Magazines Ltd 2003

Keyword: Evolution
Link ID: 3746 - Posted: 06.24.2010

Charcot-Marie-Tooth and Distal Spinal Muscular Atrophy Gene May Shed Light on Carpel Tunnel Syndrome and Lou Gehrig's Disease Bethesda, Maryland — Scientists at the National Human Genome Research Institute (NHGRI) and at the National Institute of Neurological Disorders and Stroke (NINDS) have identified the gene responsible for two related, inherited neurological disorders, and have, for the first time, directly implicated this gene and its enzyme product in a human genetic disease. The discovery supports further investigation of this gene family for additional neurological disease genes, research that may shed light on a range of disorders, including carpel tunnel syndrome, which affects the hands and the wrists, and the fatal degenerative disease amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease. NHGRI and NINDS scientists, working together at the National Institutes of Health (NIH), found the gene responsible for Charcot-Marie-Tooth (CMT) disease type 2D and distal spinal muscular atrophy (dSMA) type V. The gene, called GARS — the glycyl tRNA synthetase gene — is located on chromosome 7 and encodes, or provides the instructions to make, one of the aminoacyl tRNA synthetases, a family of enzymes vital to the cell's ability to build proteins.

Keyword: Genes & Behavior; ALS-Lou Gehrig's Disease
Link ID: 3745 - Posted: 06.24.2010

Creation of signposts detected in the first non-human species Humans are not alone in creating ‘signposts’ to help them find their way, according to new research published in the open access journal BMC Ecology. Wood mice, say scientists, move objects from their environment around using them as portable signposts whilst they explore. The finding is significant as this is the first time such sophisticated behaviour has been identified in any mammal except humans. According to the authors, “This is precisely how a human might tackle the problem of searching efficiently in a homogeneous environment – for example by placing a cane in the ground as a reference point from which to search for a set of keys dropped on a lawn.” Quick, effective navigation is vital for the wood mouse. Home-ranges are vast in comparison to the mammal’s size and consist of uniform areas, like ploughed fields, without obvious landmarks. These environments are not the same all year round, and harvest time drastically changes the availability of any ‘fixed’ landmarks, food supplies and hiding places.

Keyword: Animal Migration; Intelligence
Link ID: 3744 - Posted: 06.24.2010

'Smartness' about social life is different from smartness about SAT scores What do the brain, ovaries and nose have in common? According to new research from The Rockefeller University, these three organs help orchestrate the complex behavior called social recognition in female mice through the interaction of four genes. The findings, reported in the April 29 issue of PNAS Early Edition, help explain social interactions among female animals, and may shed light on social phobias and disorders in humans. The researchers, led by Rockefeller professor Donald Pfaff, Ph.D., show that strains of female mice that lack the genes for oxytocin and the estrogen receptors alpha and beta fail to recognize normal female mice after repeated instances when the normal animal was placed in the same space. The gene "knockout" mice also failed to investigate a new "intruder mouse" under circumstances where a genetically normal mouse would do so.

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 3743 - Posted: 04.29.2003

A new mouse study suggests fasting every other day can help fend off diabetes and protect brain neurons as well as or better than either vigorous exercise or caloric restriction. The findings also suggest that reduced meal frequency can produce these beneficial effects even if the animals gorged when they did eat, according the investigators at the National Institute on Aging (NIA). "The implication of the new findings on the beneficial effects of regular fasting in laboratory animals is that their health may actually improve if the frequency of their meals is reduced," says Mark Mattson, Ph.D., chief of the NIA's Laboratory of Neurosciences. "However, this finding, while intriguing, will need to be explored further. Clearly, more research is needed before we can determine the full impact that meal-skipping may have on health." In the study*, published in the Proceedings of the National Academy of Sciences Online Early Edition the week of April 28, 2003, Dr. Mattson and his colleagues found mice that were fasted every other day but were allowed to eat unlimited amounts on intervening days had lower blood glucose and insulin levels than either a control group, which was allowed to feed freely, or a calorically restricted group, which was fed 30 percent fewer calories daily than the control group. Despite fasting, the meal-skipping mice tended to gorge when provided food so they did not eat fewer calories than the control group. This finding in mice suggests that meal-skipping improves glucose metabolism and may provide protection against diabetes, Dr. Mattson says.

Keyword: Obesity
Link ID: 3742 - Posted: 04.29.2003

STANFORD, Calif. - Scientists have finally laid hands on the first member of a recalcitrant group of proteins called the Wnts two decades after their discovery. Important regulators of animal development, these proteins were suspected to have a role in keeping stem cells in their youthful, undifferentiated state - a suspicion that has proven correct, according to research carried out in two laboratories at Stanford University Medical Center. The ability to isolate Wnt proteins could help researchers grow some types of stem cells for use in bone marrow transplants or other therapies. The gene coding for a protein usually reveals clues about how that protein will react in the lab and how best to isolate it from other molecules. The Wnts are unusual, however, because the way they behave in the lab differs from what the gene suggests. Roeland Nusse, PhD, professor of developmental biology at the School of Medicine and one of the first to isolate a Wnt (pronounced "wint") gene, reports how his lab members overcame these hurdles in the April 27 advance online edition of the journal Nature. "We found that the protein is modified, explaining why it has been difficult to isolate," said Nusse, who is also an investigator at the Howard Hughes Medical Institute. Although the protein's structure suggests it should dissolve easily in water, Karl Willert, PhD, a postdoctoral fellow in Nusse's lab, found that an attached fat molecule makes the protein shun water and prefer the company of detergents instead.

Keyword: Stem Cells
Link ID: 3741 - Posted: 04.29.2003

By EMILY EAKIN Thomas W. Laqueur is a scholarly gumshoe with a specialty in sex. His last book, "Making Sex: Body and Gender From the Greeks to Freud" (1990), was a highly original investigation of a tantalizing mystery he had stumbled on in the archives: Why did female orgasm, long considered essential to conception, all but disappear from the historical record during the Enlightenment? Now, in "Solitary Sex: A Cultural History of Masturbation," Mr. Laqueur, a professor of history at the University of California at Berkeley, tackles another enigma from the annals of sexual history: Why did masturbation, an activity regarded with benign indifference for millennia, provoke sweeping moral and medical panic around 1700? Mr. Laqueur's preoccupations are hardly the kind destined to endear him to the cultural right. In particular, his latest tome — which features a floating, naked woman wearing an expression of glazed-eyed ecstasy on its cover and a couple dozen graphic illustrations inside — seems designed to inflame critics convinced that the academy is populated by tenured radicals bent on selling students a morally suspect and intellectually trivial bill of goods. Copyright 2003 The New York Times Company

Keyword: Sexual Behavior
Link ID: 3740 - Posted: 06.24.2010

By Dr David Whitehouse BBC News Online science editor Australopithecus fossils from caves in South Africa may have been buried about 4 million years ago, as much as 1 million years earlier than previously thought. Australopithecus is an important hominid - human ancestor - that demonstrates the transition from ape-like features to human ones. Its kind were first discovered in East Africa and lived about four million years ago. Researchers used a technique that measured the decay of radioactive isotopes formed when the fossil was on the surface, but which declined when it was buried. The new dates make the South African fossils as old as similar specimens found in East Africa, forcing a revision of how far scientists believe Australopithecus ranged. The fossils were from the caves and quarries at Sterkfontein, 50 km northwest of Johannesburg, that are some of the richest hominid fossil sites in the world. About 500 specimens have been recovered there since the 1936 discovery of the first adult Australopithecus. (C) BBC

Keyword: Evolution
Link ID: 3739 - Posted: 04.27.2003

By DIRK OLIN Last month, a quartet of academics published ''What's Wrong With the Rorschach?'' -- attacking a test administered to more than a million people worldwide each year. According to recent surveys by the American Psychological Association, 82 percent of its members ''occasionally'' and 43 percent ''frequently'' use the test, in which subjects speculate about five colored and five black-and-white inkblots. Test-givers in turn interpret the answers to diagnose mental illness, predict violent behavior and reveal suppressed trauma. Their conclusions are applied to everything from child-custody disputes to parole reviews. According to James M. Wood, an associate professor of psychology at the University of Texas at El Paso and one author of the book, tarot cards would work almost as well. Wood and his colleagues level basic criticisms against the inkblot test's foundations. They say it lacks accurate norms to serve as benchmarks for comparing healthy and sick patients. Reliability is also at issue, because many scores are determined by test-givers' subjective interpretations. And last, they contend that virtually none of the scores are scientifically valid, because they neither measure what they claim nor can be consistently correlated with other tests or diagnoses. The Rorschachers simply harbor a ''romantic'' devotion to the test's efficacy, Wood says, one based on ''an uncritical, even gullible, acceptance of ridiculous claims that the Rorschach is like a medical test, a sort of brain scan.'' In the few years since the critics first began making their arguments, a sometimes visceral academic firefight has broken out. Rorschachers have hired a lobbyist, and one of the test's historic champions has been joined by younger acolytes in churning out hotly disputed studies in its defense. Copyright 2003 The New York Times Company

Keyword: Miscellaneous
Link ID: 3738 - Posted: 04.27.2003

NewScientist.com news service A mother's poor diet around the time of conception can cause premature birth, according to new research in sheep. If the same is true for humans, and there is some evidence that it is, bad nutrition could account for some of the 40 per cent of premature births that remain unexplained in developed countries. Premature birth is by far the most common cause of death in newborn babies, and its incidence in western societies has increased in the past decade. Previous studies have shown that reduced maternal nutrition - in women with anorexia, for example - can cause lower birthweight in babies born after a full-length pregnancy. © Copyright Reed Business Information Ltd.

Keyword: Development of the Brain
Link ID: 3737 - Posted: 06.24.2010

MINNEAPOLIS/ST. PAUL - Researchers at the University of Minnesota provide evidence for the first time that stem cells derived from adult bone marrow and injected into the blastocyst of a mouse can differentiate into all major types of cells found in the brain. The results of the research are published as the lead article in the April 25, 2003 issue of Cell Transplantation. The potential of these adult stem cells, termed multipotent adult progenitor cells (MAPCs), were the subject of research reported in Nature in June 2002. The research reported this week in Cell Transplantation takes a specific look at the ability of MAPCs to develop into cells typically found in the brain. Adult stem cells were injected into a mouse blastocyst, an early embryonic stage of a mouse. The result is the birth of a chimerical animal an animal that shows the presence of both the cells from the host mouse as well as cells that have developed from the transplanted stem cells. Within the brain, the transplanted stem cells developed into nerve cells that typically conduct electrical impulses, glial cells that provide support to the nerve cells, and myelin-forming cells that enhance the conduction of electrical impulses by nerve cells. “This research takes our findings a step further,” said principal investigator Walter C. Low, Ph.D., department of Neurosurgery, University of Minnesota Medical School.

Keyword: Stem Cells
Link ID: 3736 - Posted: 06.24.2010

The Hybrot, a small robot that moves about using the brain signals of a rat, is the first robotic device whose movements are controlled by a network of cultured neuron cells. Steve Potter and his research team in the Laboratory for Neuroengineering at the Georgia Institute of Technology are studying the basics of learning, memory, and information processing using neural networks in vitro. Their goal is to create computing systems that perform more like the human brain. Potter, a professor in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University, presented his most recent findings last month during the Third International Conference on Substrate-Integrated Microelectrodes in Texas.

Keyword: Robotics
Link ID: 3735 - Posted: 04.26.2003

In science fiction movies, robots are often depicted as rampaging metallic monsters striking back against their creators, and the fact that they’re “not like us” is what makes them believable as villains. “Actually, Hollywood or the movie industry is way ahead of reality,” says Yoseph Bar-Cohen, senior research scientist at NASA’s Jet Propulsion Lab. “They are actually pushing it and portraying it beyond what we can do today. “But,” he adds, “it’s good to have this. We need to see the implications of technology like that, both the positive and the negative. And the more vision we have, the better we are, because we can perceive the possibilities.” © ScienCentral, 2000-2003.

Keyword: Robotics; Emotions
Link ID: 3734 - Posted: 06.24.2010

By SANDRA BLAKESLEE Sir Bernard Katz, who shared the 1970 Nobel Prize for Physiology or Medicine for his work explaining how messages are transmitted between nerves and muscles, died on Sunday. He was 92. He lived in London since just after World War II. Sir Bernard was honored, along with the physiologists Ulf von Euler and Julius Axelrod, for describing in separate lines of research precisely how brain cells talk to one another and get the body moving. Copyright 2003 The New York Times Company

Keyword: Miscellaneous
Link ID: 3733 - Posted: 04.25.2003

People have been keeping track of time for much longer than wristwatches have been around. How does the brain do it? Designing experiments to reveal how the brain senses time is devilishly tricky, but new work with monkeys shows that neurons in a part of the brain involved with spatial processing might double as timekeepers. The experiment involved monkeys looking at lights, which stimulates several parts of the brain. First off, the brain begins to process flashes and other sensory information in areas collectively known as the sensory cortex. If the eyes respond by darting one way or another, other regions kick in. One of these is an area known as the lateral intraparietal area, or LIP, which helps the brain decide to take action. The LIP offered a key clue about the brain's sense of timing. Copyright © 2003 by the American Association for the Advancement of Science.

Keyword: Vision
Link ID: 3732 - Posted: 06.24.2010

The way that neurons are linked together in the brain has long fascinated both physicists and biologists. Researchers at the University of Tel-Aviv in Israel have now shown for the first time that neurons can self-organize themselves into electrically active clusters of cells in the laboratory. The clusters are linked together by bundles of axons (R Segev et al. 2003 Phys. Rev. Lett. 90 168101). Eshel Ben-Jacob and colleagues used an in-vitro technique to study the effect of cell density on the formation of neuronal clusters. The researchers grew cultures of rat-brain neurones on top of a silicon nitride surface and followed the development of the networks with time-lapse video recording. They found that the network, which is initially uniform, separates by the creation of 'borders' that break it into separate 'basins'. Each basin then collapses into a cluster, which remains intact until it degrades 3 to 4 weeks later (see figure 1). Copyright © IOP Publishing Ltd

Keyword: Development of the Brain
Link ID: 3731 - Posted: 06.24.2010

A research team based at the University of Chicago has traced increased susceptibility to bipolar disorder to two overlapping genes found on the long arm of chromosome 13. The study, published in the May 2003 issue of the American Journal of Human Genetics, is the first to implicate this gene complex, and the second to tie any gene, to the development of bipolar disorder, which affects 2 million American adults. A previous study found that the same gene complex increases risk for schizophrenia. The current finding adds credence to the emerging notion that the same genes may be contribute to both disorders. "The discovery of susceptibility genes for psychiatric disorders has been one of the most intractable problems in human genetics," said Elliot Gershon, M.D., professor and chairman of psychiatry at the University of Chicago and a co-author of the study. "In the past two years, we seem to have reached a watershed for psychiatric gene discovery, with the identification of genes that increase risk of bipolar disorder and schizophrenia. After years of false starts and unfulfilled promises, we have begun to make real progress."

Keyword: Schizophrenia; Genes & Behavior
Link ID: 3730 - Posted: 04.25.2003

Can Help Ashkenazi Jewish Children Who are Born Deaf and Have Progressive Loss of Sight Bethesda, Maryland — Deafness in both ears and progressive loss of vision due to retinitis pigmentosa are the indicators of Usher syndrome, a genetic dual deficit disorder. There are three clinical subtypes of Usher syndrome, the most severe of which is Usher type 1 (USH1). This syndrome involves deafness at birth, progressive blindness and balance problems. In 1861, a physician working in Berlin described the clinical features of Usher syndrome in Jewish individuals. Now, 140 years later, there is an opportunity to offer help to those individuals who inherit this syndrome as reported in the April 24, 2003 New England Journal of Medicine. A significant collaboration across four institutions was led by scientists at the National Institute on Deafness and Other Communication Disorders at the National Institutes of Health including Thomas B. Friedman, Ph.D., Chief, Laboratory of Molecular Genetics, Tamar Ben-Yosef, Ph.D., the key scientist on this project, and Andrew J. Griffith, M.D., Ph.D. Additional collaborators on this project were Seth Ness, M.D., Ph.D., Mount Sinai School of Medicine, Karen Avraham, Ph.D. at the Department of Human Genetics and Molecular Medicine, Sackler School of Medicine, Tel Aviv University, and Harry Ostrer, M.D., and Carole Oddoux, Ph.D. at the Department of Molecular Genetics, NYU Medical Center. Dr. Ben-Yosef identified a mutation, R245X, of an Usher syndrome type 1 gene, PCDH15, which appears to account for a large proportion of USH1 in the Ashkenazi Jewish population today. Ashkenazi describes those Jewish people who came from eastern Europe.

Keyword: Genes & Behavior; Hearing
Link ID: 3729 - Posted: 06.24.2010