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Nature Neuroscience
Sanctions on scientific publication
The perception of a stimulus can result in an emotional response, as we all know, but modulation of perception by emotion has been more difficult to demonstrate. A new study combines imaging and patient data to point to an anatomical substrate for such an effect, raising important implications regarding how sensory-processing impairments might arise in affective disorders.
Newborn neurons in the cerebellum migrate along radial glial processes through a series of distinct steps. A report in this issue uses live imaging to grant us a close-up view of the cytoskeletal structures and regulating proteins involved in this migration.
In humans, recollection and familiarity represent qualitatively distinct kinds of memory. A recent study in Nature applied methods commonly used in human research to rats and suggests that their recognition memory may consist of similarly distinct components.
Decision making, performance and outcome monitoring in frontal cortical areas
The rostral cingulate zone and the orbitofrontal cortex are active when people monitor the consequences of adaptively changing behavior. A new fMRI study distinguishes their functions, implicating them in situations with different contexts and timing.
Festina lente: Late-night thoughts on high-throughput screening of mouse behavior
John C Crabbe
& Richard G M Morris
Fibrillar amyloid deposition leads to local synaptic abnormalities and breakage of neuronal branches
Amyloid plaques are a hallmark of Alzheimer disease, but their importance in its pathogenesis is controversial. By neuronal labeling and transcranial two-photon imaging, we show in a transgenic mouse model of Alzheimer disease that dendrites passing through or near fibrillar amyloid deposits undergo spine loss and shaft atrophy, and nearby axons develop large varicosities, together leading to neurite breakage and large-scale, permanent disruption of neuronal connections. Thus, fibrillar amyloid deposition is more detrimental to neuronal circuitry than previously thought, underscoring the importance of prevention and early clearance of plaques.
Distinct classes of GABAergic synapses target restricted subcellular domains, thereby differentially regulating the input, integration and output of principal neurons, but the underlying mechanism for such synapse segregation is unclear. Here we show that the distributions of two major classes of GABAergic synapses along the perisomatic and dendritic domains of pyramidal neurons were indistinguishable between primary visual cortex in vivo and cortical organotypic cultures. Therefore, subcellular synapse targeting is independent of thalamic input and probably involves molecular labels and experience-independent forms of activity.
A de novo mutation affecting human TrkB associated with severe obesity and developmental delay
An 8-year-old male with a complex developmental syndrome and severe obesity was heterozygous for a de novo missense mutation resulting in a Y722C substitution in the neurotrophin receptor TrkB. This mutation markedly impaired receptor autophosphorylation and signaling to MAP kinase. Mutation of NTRK2, which encodes TrkB, seems to result in a unique human syndrome of hyperphagic obesity. The associated impairment in memory, learning and nociception seen in the proband reflects the crucial role of TrkB in the human nervous system.
Unraveling multisensory integration: patchy organization within human STS multisensory cortex
Although early sensory cortex is organized along dimensions encoded by receptor organs, little is known about the organization of higher areas in which different modalities are integrated. We investigated multisensory integration in human superior temporal sulcus using recent advances in parallel imaging to perform functional magnetic resonance imaging (fMRI) at very high resolution. These studies suggest a functional architecture in which information from different modalities is brought into close proximity via a patchy distribution of inputs, followed by integration in the intervening cortex.
In a functional magnetic resonance imaging study, we investigated how people solve mathematically equivalent problems presented in two alternative formats: verbal, story format or symbolic, equation format. Although representation format had no effect on behavior, anterior prefrontal activation was greater in the story condition and posterior parietal activation was greater in the equation condition. These results show that there exist alternative neural pathways that implement different and yet equally efficient problem-solving strategies.
Par6? signaling controls glial-guided neuronal migration
David J Solecki, Lynn Model, Jedidiah Gaetz, Tarun M Kapoor
& Mary E Hatten
Focal adhesion kinase in netrin-1 signaling
Xiu-rong Ren, Guo-li Ming, Yi Xie, Yan Hong, Dong-mei Sun, Zhong-qiu Zhao, Zhu Feng, Qiang Wang, Sangwoo Shim, Zhou-feng Chen, Hong-jun Song, Lin Mei
& Wen-cheng Xiong
Activation of FAK and Src are receptor-proximal events required for netrin signaling
Weiquan Li, Jeeyong Lee, Haris G Vikis, Seung-Hee Lee, Guofa Liu, Jennifer Aurandt, Tang-Long Shen, Eric R Fearon, Jun-Lin Guan, Min Han, Yi Rao, Kyonsoo Hong
& Kun-Liang Guan
Netrin requires focal adhesion kinase and Src family kinases for axon outgrowth and attraction
Guofa Liu, Hilary Beggs, Claudia Jürgensen, Hwan-Tae Park, Hao Tang, Jessica Gorski, Kevin R Jones, Louis F Reichardt, Jane Wu
& Yi Rao
A Denise R Garcia, Ngan B Doan, Tetsuya Imura, Toby G Bush
& Michael V Sofroniew
Hedgehog signaling from the ZLI regulates diencephalic regional identity
Clemens Kiecker
& Andrew Lumsden
Activity-dependent transcription regulation of PSD-95 by neuregulin-1 and Eos
Jianxin Bao, Hana Lin, Yannan Ouyang, Debin Lei, Abdullah Osman, Tae-Wan Kim, Lin Mei, Penggao Dai, Kevin K Ohlemiller
& Richard T Ambron
Interactions between decision making and performance monitoring within prefrontal cortex
Mark E Walton, Joseph T Devlin
& Matthew F S Rushworth
Amir Amedi, Agnes Floel, Stefan Knecht, Ehud Zohary
& Leonardo G Cohen
Distant influences of amygdala lesion on visual cortical activation during emotional face processing
Patrik Vuilleumier, Mark P Richardson, Jorge L Armony, Jon Driver
& Raymond J Dolan
Erratum: Rhythmic arm movement is not discrete
Lunar and Planetary Information Bulletin
A overview of the complexities and mysteries of Saturn's enigmatic and largest moon
-- NASA's Airborne Infrared Observatory Sees the "First Light"
-- WISE Makes Progress on its Space Rock Catalog
-- NASA Radar Finds Ice Deposits at Moon's North Pole; Additional Evidence of Water Activity on Moon
-- Phoenix Mars Lander Does Not Phone Home, New Image Shows Damage
-- Geometry Drives Selection Date for 2011 Mars Launch
-- NASA Spacecraft Penetrates Mysteries of Martian Ice Cap
-- Rover Finds Clue to Mars' Past and Environment for Life
-- Mars Spacecraft Snaps Photos Chosen by Public
-- Hayabusa Capsule Recovered Intact
-- See Spot on Jupiter. See Spot Glow.
-- New Impact on Jupiter
-- Cassini and Amateurs Chase Storm on Saturn
-- PBS Show Investigates Artwork on the Moon
-- Next-Generation Suborbital Researchers Conference
-- 41st Lunar and Planetary Science Conference
-- First International Conference on Mars Sedimentology and Stratigraphy
-- Astrobiology Science Conference 2010
-- Second International Planetary Dunes Workshop
-- Io Workshop 2010
-- NASA Supplemental Education Proposals for Research Investigations
-- Moon Zoo
-- Virtual Tour of Galilean Satellites
-- New LPI Solar System Activities
-- New NASA Website Launches Kids on Mission to Save Our Planet
-- 3rd Annual Lunar Science Forum
-- Education and Public Outreach Symposium
-- New "Discoveries in Planetary Science" PowerPoints
-- Windows to the Universe Welcomes Collaborators
-- Astronomical Society of the Pacific Podcasts
-- Former LPI Intern Becomes NASA Deputy Associate Administrator for Exploration
-- Koeberl Named as Director of Museum of Natural History
-- NASA's Digital Learning Network Teachers Earn Prestigious Award
-- NASA Ames Center Diretor Receives Arthur C. Clarke Award
-- LPI Welcomes Summer Interns
-- Space Operations Award Goes to Mars Rover Team
-- NASA Announces 2010 Carl Sagan Fellows
-- Science Team from Ames Research Center Wins 2009 NASA Software of Year Award
-- Lunine Elected as Member of National Academy of Sciences
-- DPS Prize Winners Announced
-- Brian Mason
-- Gero Kurat
-- Finn Ulff Moller
-- Zdenek Ceplecha
-- Aaron Cohen
-- Eric Essene
-- Floyd Herbert
-- Ardis Nier
New products of interest to the community
Upcoming scientific conferences and workshops
Scientific American
A Bit Cold: Physicists Devise a Quantum Particle "Refrigerator"
Call it the little chill. A group of theoretical physicists has mapped out the physics framework for what may be the smallest refrigerators imaginable. Each device would target just one quantum bit, or qubit, for cooling, and would require just one or two additional quantum particles to do the job. [More]
Customers Say They'd Pay More for Items They Can Handle
Bookshops and DVD stores are closing up. No surprise, because who would pay more at the store when you can get it cheaper online? A bunch of Caltech undergrads, that's who. Researchers found that the students were willing to pay 50 percent more for just about anything--DVD’s but also potato chips, Snickers bars, mugs--as long as the item was in front of them, as opposed to just the item’s image or text description. That study appears in the American Economic Review . [Benjamin Bushong et al., http://bit.ly/aTK70Y ] [More]
Four dead in San Francisco suburb gas line inferno
* 38 homes destroyed * Gas line belongs to utility PG&E
MIND Reviews: Philosophy Meets Neuroscience
Do we have free will? Is there meaning to life? A slew of new books provide some insights into how scientists are supplementing Plato with PET scans, hoping to answer these questions. In My Brain Made Me Do It: The Rise of Neuroscience and the Threat to Moral Responsibility (Prometheus Books, 2010), Eliezer J. Sternberg examines studies that pinpoint areas of the brain associated with exercising free will and suggests that our ability to decide makes us largely responsible for our actions.
Recommended: The 50 Most Extreme Places in Our Solar System
The 50 Most Extreme Places in Our Solar System by David Baker and Todd Ratcliff. [More]
Space Colonists Could Use Bacteria to Mine Minerals on Mars and the Moon
Microbes currently are used in mining to help recover metals such as gold, copper and uranium. Now researchers suggest bacteria could be enlisted for "bio-mining" in space , to extract oxygen, nutrients and minerals from extraterrestrial bodies such as the moon and Mars for use by future colonists there. [More]
Winging It: Flying Fish Aerodynamics Directly Measured for the First Time
A fish out of water is not usually a graceful or impressive sight, unless that fish is flying--or hovering inside a laboratory wind tunnel. [More]
By Janelle Weaver Practice makes perfect when it comes to remembering things, but exactly how that works has long been a mystery. [More]
How Much Global Warming Is Guaranteed Even If We Stopped Building Coal-Fired Power Plants Today?
Humanity has yet to reach the point of no return when it comes to catastrophic climate change, according to new calculations. If we content ourselves with the existing fossil-fuel infrastructure we can hold greenhouse gas concentrations below 450 parts per million in the atmosphere and limit warming to below 2 degrees Celsius above preindustrial levels--both common benchmarks for international efforts to avoid the worst impacts of ongoing climate change--according to a new analysis in the September 10 issue of Science . The bad news is we are adding more fossil-fuel infrastructure--oil-burning cars, coal-fired power plants, industrial factories consuming natural gas--every day. [More]
New MRI maps assess connectivity to establish "brain age" curve for children and adults
As children grow, brambles of short brain connections are gradually pruned down to longer, stronger neural pathways. Research has shown this trend to follow a fairly standard curve during normal development to adulthood, and scientists are now using this information to create predictive models of brain maturation. [More]
Bowerbirds Arrange Objects to Make Themselves Look Bigger
The first time you visit your boyfriend’s place, he no doubt tidies up, to give you the illusion that he doesn’t live like an animal. Well, animals, too, can use optical illusions to woo a mate. Take the bowerbird. [More]
Shot in the ARM: New chip design aims to boost mobile gadget speed and performance
Smart phones have become today's PCs, enabling mobile connection to the Internet, messaging and thousands of different apps. But for the smart phone to progress to an even higher level of sophistication and acceptance, it's going to need microprocessors, or chips, that can supply even more power, without draining the battery. No problem, says ARM Ltd. , a Cambridge, U.K. chip designer that specializes in mobile devices. [More]
In the Market for Pollution: Carbon Trade or Carbon Con?
NEW YORK--A company recycles a product, doing its part for the environment through reuse, only to be told it's worth more to destroy it. Welcome to the wonderful world of the carbon market, especially for a company that deals in refrigerants. These gases, culprits in no less than two environmental crimes--the ozone hole and climate change--are required to efficiently cool your food and beverages. Yet, chlorofluorocarbons, to give them their proper name, are potent molecules that both exacerbate the blanket of greenhouse gases warming the world as well as chew up the stratospheric ozone layer protecting the planet's inhabitants from excess doses of ultraviolet sunlight.
Holst's Planets Revisited: New York City Band Follows in Composer's Footsteps
In 1916, when British composer Gustav Holst finished his famous orchestral suite The Planets , the solar system was thought of as a relatively simple and unique place. Clyde Tombaugh, the American astronomer who would discover Pluto in 1930, was just a schoolboy when Holst's landmark composition was written, and the sum total of known planets was a tidy eight. [More]
Smart Jocks: Sports Helps Kids Classroom Performance (preview)
Despite frequent reports that regular exercise benefits the adult brain, when it comes to schoolchildren, the concept of the dumb jock persists. The star quarterback stands in stark contrast to the math-team champion. After all, the two types require seemingly disparate talents: physical prowess versus intellect. Letting kids run around or throw a ball seems, at best, tangential to the real work of learning and, at worst, a distraction from it. Parents, teachers and education policy makers have pitted athletics against academics even as they trumpet exercise as an antidote to obesity and poor health. From preschool onward, teachers encourage children to sit still rather than scamper. Many schools have cut back on physical education to make room for the three R’s. And when student scores on standardized tests become of primary importance to parents, politicians or other stakeholders in the education system, educators may feel pressured to direct students toward academic pursuits and away from athletic ones.
Lunar Pencil Lead: Graphite Found in Moon Rock Collected During Apollo 17
Humans have not set foot on the moon since Apollo 17 in 1972, but those missions are still producing surprises. An analysis of a collected rock has produced the first solid evidence for graphite, the form of carbon commonly used as pencil lead, in a lunar sample. Andrew Steele, an astrobiologist at the Carnegie Institution of Washington, and his colleagues reported in the July 2 Science that they found dozens of graphite particles in a small, dark patch on the sample--a region just 0.1 square millimeter in area--as well as seven needle-shaped rolls of carbon called graphite whiskers. Other samples have yielded traces of the element implanted by the solar wind or locked up in carbide compounds, but discrete pockets of graphite of this relatively large size appear to be a unique find.
Cassini spacecraft photographs four Saturnian satellites
Deepwater doom: Extinction threat for world's smallest sea horse
The Gulf of Mexico oil spill this year and subsequent cleanup efforts could drive the world's smallest sea horse into extinction, warns the Zoological Society of London and its marine conservation organization Project Seahorse . The tiny dwarf sea horse ( Hippocampus zosterae ), which grows to a maximum length of 2.5 centimeters, can be found only in the ocean waters off the Gulf Coast.
Curious carnivorous dinosaur had a humpback
Some dinosaurs had feathers ; others had extendable claws or elaborate spikes . But a newly described species is the first to have been found with a distinctively humped back. [More]
Psilocybin found to ease end-of-life anxiety in small study of patients with fatal cancer
Can the active ingredient in " magic mushrooms " help those with terminal cancer cope with their fate? That was the question asked by researchers, who published the results of their investigation September 6 in Archives of General Psychiatry . [More]
Burn, baby, burn: Student-engineered stoves put to the test by Tanzanian women
Editor's Note: Students from Dartmouth's Thayer School of Engineering are working in Tanzania to help improve sanitation and energy technologies in local villages. The student-led group , known as Humanitarian Engineering Leadership Projects (HELP), will file dispatches from the field during their trip. This is their ninth blog post for Scientific American. [More]
In the Market for Pollution: Selling the Blue Sky
NEW YORK--There are any number of ways to make money trading, though some prefer the term gambling. That's because the financial world is full of innovation these days--even in the wake of the Great Recession--which primarily means inventing new instruments to trade. One can still trade the mortgage-backed securities that helped derail the global economy or corporate debt repackaged as bonds. Enron helped pioneer the trade in "physical" electricity, actual power available for purchase on the grid and only physical in the sense that the infrastructure to transport it is more visible than an odorless, colorless greenhouse gas. Both are now lucrative markets, but certainly electricity, despite its physics, is more stable.
Open-source personal robotics seeks a community to make it affordable [video]
Until someone develops a common platform for building robots (think of the combination of Windows and Intel that has made PCs so accessible), the technology will remain elusive to the general public. At least that's the contention of Willow Garage, Inc., a Menlo Park, Calif. company that Wednesday made its PR2 personal robot available to the public . [More]
Organic Strawberries Beat Conventionally Grown in Test Plots
Some consumers buy organically grown foods because they believe the products are healthier, tastier and better for the environment. But is this assessment true? [More]
Quantum Light Switch: Single Atom Acts as a Transistor for Photons
Point two laser beams so that they cross each other, and each goes through as if the other one did not exist. Light rays cannot interact with other light rays--or can they? With the help of a single atom, physicists have devised a system in which one light beam can turn another on or off. Such a light switch could serve as the basic component of futuristic optical quantum computers and may help open the way to a quantum version of the Internet, which would offer unbreakable data security. The device makes use of a phenomenon called electromagnetically induced transparency, in which a laser beam can render opaque clouds of atoms temporarily transparent to a narrow wavelength of light. The cloud can then act as a switch for a second beam, either letting it through or blocking it. The result is similar to what happens with transistors in electronic circuits, where a voltage applied at one electrode controls whether current can flow between two other electrodes.
Prescription for a Healthier Brain: Coffee and Cigarettes?
Inspired by human studies showing that avid coffee drinkers and smokers have a lower risk of Parkinson’s disease, scientists at the University of Washington decided to see what java and cigarettes do to fruit flies. [More]
NASA panel weighs asteroid danger
By Eugenie Samuel Reich Some time in the next decade, a U.S. [More]
Questions over ghostwriting in drug industry
By Ewen Callaway Journal articles on hormone replacement therapy (HRT) ghostwritten by medical writers employed by the pharmaceutical industry serially understated the treatment's risks and promoted unapproved uses, according to an analysis of industry documents. The analysis, published September 7 in the journal PLoS Medicine , is based on some 1,500 e-mails, contracts and other documents made public in July 2009, after The New York Times and PLoS Medicine successfully argued that their release would be in the public interest. [More]
Cheaper treatment for HIV-infected infants could also be more effective
Babies born to mothers with HIV have a much smaller risk of getting the virus themselves if medical personnel administer preventive drugs, such as nevirapine, at birth to the moms and their newborns. Nevertheless, a small percentage of those infants will end up getting the disease anyway. And without treatment, some 62 percent of HIV-positive children die before the age of two. [More]
Rare victory in fight against melanoma
Patients with advanced melanoma rarely live for more than a year after their diagnosis--a prognosis that has not improved for more than 30 years. [More]
Editor's Note: Students from Dartmouth's Thayer School of Engineering are working in Tanzania to help improve sanitation and energy technologies in local villages. The student-led group , known as Humanitarian Engineering Leadership Projects (HELP), will file dispatches from the field during their trip. This is their eighth blog post for Scientific American. [More]
Report: 21 percent of Africa's freshwater species threatened with extinction
More than a fifth of Africa's freshwater species are threatened with extinction , and their disappearance could threaten livelihoods across the continent, according to a new study by the International Union for Conservation of Nature (IUCN). The study, conducted for the IUCN's Red List of Threatened Species, assessed 5,167 African freshwater species over a five-year period. Two hundred scientists contributed to the report, which covers fish, mollusks, crabs, aquatic plants and aquatic insects such as dragonflies and damselflies.
NEW YORK--When convincing someone to trade in a commodity that cannot be seen or touched, it's best to hold their hand--even if only by telephone. Standing while talking helps, too, at least for broker Lenny Hochschild, who specializes in convincing everyone from agribusiness to electric utilities to buy and sell in a market that doesn't exist yet--a U.S. market for the right to emit carbon dioxide, the most ubiquitous greenhouse gas changing the global climate. This is possibly the newest market in the world, a would-be global attempt to create a trade in the greenhouse gas emissions from any nation's fleet of cars, household refrigerators, electric power plants, factories, even farms. It's an attempt to peel back the smothering blanket of global warming by giving people a financial incentive to reduce emissions under an economic concept known as cap and trade.
Mice Show Heritable Desire for Exercise
Always finding excuses to skip the gym? Congrats--you might be able to blame your genes. Because the mere desire to exercise may be inherited, at least in mice. So says a study in the journal Proceedings of the Royal Society B . [Theodore Garland Jr. et al., http://bit.ly/crWNGd ] [More]
You Are What You Touch: How Tool Use Changes the Brain's Representations of the Body
All our experience of the world, and ability to act on it, are channelled through our body. The pioneering computer scientist, Alan Turing, correctly realised the human mind is special not particularly because of its computing power, but because the body provides it with a unique interface to the world. Current research in psychology and neuroscience is probing how the brain represents the body. Recent advances have revealed that body representation is fundamentally multisensory, arising from the combination of many different sensory signals. These include classical “senses,” such as touch and vision, and also much more specific signals, such as the flexion or extension of each muscle, which define the body’s posture in space. This information is integrated to construct a multisensory representation of the current state of the body. Intriguingly, multisensory signals also affect what we perceive our body to be like, for example by making us feel like a rubber hand really is our hand! Our thoughts about what our body is are highly flexible, and track the multisensory inputs that the brain receives. A common illustration of just how flexible the sense of our body is comes from changes in the brain’s representation of the body due to tool use. Humans, and some other animals, are able to use tools as additions to the body. When we use a long pole to retrieve an object we couldn’t otherwise reach, the pole becomes, in some sense, an extension of our body. Is this merely a poetic way of speaking, or does the brain actually incorporate the tool into its representation of the body? Studies of monkeys learning to use a rake to obtain distant objects show that this may be more than a mere metaphor. Multisensory brain cells respond both to touch on the hand or visual objects appearing near the hand. When the monkeys used the rake, these cells began to respond to objects appearing anywhere along the length of the tool, suggesting the brain represented the rake as actually being part of the hand.
You Must Remember This: What Makes Something Memorable?
One of the signature discoveries of cognitive neuroscience is that a structure called the hippocampus, deep within the brain, is intimately involved in creating memories. This fact was dramatically illustrated by a singular patient, Henry Molaison, who experienced severe epileptic seizures. In 1953, when Molaison was 27, doctors removed his hippocampus and nearby areas on both sides of his brain. The operation controlled his epilepsy, but at a price--from that time on, he was unable to remember the things that happened to him. He could learn skills, such as mirror writing, but would be puzzled by his expertise, because he could not recall having acquired it. H.M., as he was known during his lifetime to protect his privacy, taught scientists three lessons. First, certain brain structures--the hippocampus and the amygdala, the brain’s emotion center--specialize in remembering. Second, there are different kinds of memory--the ability to recall facts, or personal experiences, or physical skills like riding a bike--each with its own properties. Third, memory is distinct from the brain’s intellectual and perceptual abilities.
8 of the Most Extreme Places in the Solar System [Slide Show]
The universe is a mighty big place, but there is no shortage of amazement right here in our celestial neighborhood. From Venus's searing surface temperatures, hot enough to melt lead, to Jupiter's Great Red Spot, a storm that has been raging for hundreds of years, to the cryovolcanoes of the Saturnian moon Enceladus , the solar system boasts plenty of extreme locales. [More]
Rummaging for a Final Theory: Can a 1960s Approach Unify Gravity with the Rest of Physics?
Turning the clock back by half a century could be the key to solving one of science’s biggest puzzles: how to bring together gravity and particle physics. At least that is the hope of researchers advocating a back-to-basics approach in the search for a unified theory of physics. In July mathematicians and physicists met at the Banff International Research Station in Alberta, Canada, to discuss a return to the golden age of particle physics. They were harking back to the 1960s, when physicist Murray Gell-Mann realized that elementary particles could be grouped according to their masses, charges and other properties, falling into patterns that matched complex symmetrical mathematical structures known as Lie (“lee”) groups. The power of this correspondence was cemented when Gell-Mann mapped known particles to the Lie group SU(3), exposing a vacant position indicating that a new particle, the soon to be discovered “Omega-minus,” must exist.
Indonesian volcano blows again, biggest eruption yet
By Tarmizy Harva BERASTEPU, Indonesia, Sept 7 (Reuters) - An Indonesian [More]
Aquatic conservation efforts pay off
By Richard A. [More]
Ancient Brewmasters Made Medicinal Beer
In 1980, a scientist looking at bone fragments under an ultraviolet microscope noticed the bones were glowing green--a hallmark of the antibiotic tetracycline. The drug latches onto calcium and gets deposited in bone. Nothing unusual. Except these bones were from a Nubian mummy buried 1,600 years ago in Sudan--long before scientists discovered tetracycline, in 1948. [More]
Contemplating the end of the world, math, mystery and other things
I suffer from eschatological obsession. That is, I spend lots of time brooding about ends. So the cover of the September Scientific American --which reads simply "the end."--made me all shivery, like when I hear the spooky sitar opening of The Doors' apocalyptic rock poem "The End." (I'm never more Freudian than when I hear Morrison's Oedipal yowl.) [More]
Man's new best friend? A forgotten Russian experiment in fox domestication
Dmitri K. Belyaev, a Russian scientist, may be the man most responsible for our understanding of the process by which wolves were domesticated into our canine companions. Dogs began making for themselves a social niche within human culture as early as 12,000 years ago in the Middle East . But Belyaev didn’t study dogs or wolves; his research focused instead on foxes. What might foxes be able to tell us about the domestication of dogs? Domesticated animals of widely different species seem to share some common traits: changes in body size, in fur coloration, in the timing of the reproductive cycle. Their hair or fur becomes wavy or curly; they have floppy ears and shortened or curly tails. Even Darwin noted , in On the Origin of Species, that “not a single domestic animal can be named which has not, in some country, drooping ears.” Drooping ears is a feature that does not ever occur in the wild, except for in elephants. And domesticated animals possess characteristic changes in behavior compared with their wild brethren, such as a willingness or even an eagerness to hang out with humans.
Why a Good Deal Can Seem Unfair