Research Reveals Why Hair Turns Gray

Researchers at the Federation of American Societies for Experimental Biology (FASEB) have discovered the reason that hair turns gray as we age.

Gray hair results from a natural build-up over time of hydrogen peroxide (H₂O₂) in hair follicles, essentially bleaching the hair from within. This accumulation is cause by a reduction of a certain enzyme called catalase that breaks down hydrogen peroxide into water and oxygen. Hair follicles cannot repair the damage caused by hydrogen peroxide because of low levels of other enzymes methionine sulfoxide reductase (MSR) A and B that normally serve this function.

At the same time, the high levels of hydrogen peroxide and low levels of MSR A and B also disrupt the formation of the enzyme tyrosinase, which is responsible for the production of the natural pigment melanin. Researchers also speculate that a similar process is responsible for loss of pigment in certain skin conditions such as leukoderma.

These results were published in a recent edition of the FASEB Journal.

Source: ScienceDaily

Most Detailed Lunar Map Completed

An international team of scientists lead by the National Astronomical Observatory of Japan have completed the most detailed map of the Moon ever produced.

Using the laser altimeter on board the Japanese Selenological and Engineering Explorer (SELENE) satellite, the Moon's surface was mapped at an unprecedented 15-km resolution from pole to pole, including its dark side. New craters were discovered and the stiffness of the crust was calculated from the roughness of the lunar surface. The stiffness of the crust is a measure of subsurface water, and the Moon's surface was revealed to be too stiff to contain any liquid water, even deep within the crust.

Previous maps of the Moon include those of the 1970's Apollo program as well as the unmanned 1994 Clementine mission. Clementine offered a resolution between 20 and 60 km, and did not map the complete surface. The SELENE satellite map will serve as a guide for future lunar exploration, such as the search for mineral resources.

This map was published in the February 13th issue of Science.

Source: ScienceDaily

"Hidden Order" of Materials Phase Change Solved

Scientists at Uppsala University have solved a 24-year-old problem of how different phases form in materials at various temperature and pressure changes.

Many materials possess a clear phase transition (i.e., liquid to solid) as the temperature cools below a certain critical temperature but the mechanism behind the reordering of the structure was left unexplained, or called the "hidden order." Extremely small magnetic fluctuations on the atomic level have been discovered that prompt changes in the properties of the material, giving rise to a different phase of that material.

Under ordinary conditions, this magnetic excitation is too weak to affect the bulk of the material. The "hidden order" remained one of the largest questions in the field of material science, as knowledge of the function of these properties can lead researchers to manipulate and construct more exotic materials with the desired characteristics, such as superconductors.

These results were published in the February 22nd edition of Nature Materials.

Source: ScienceDaily

Molecular "Decoy" Drives Cancer Cells to Suicide

Researchers at the Curie Institute have developed a molecular "decoy" that mimics DNA damage and drives cancer cells to destroy themselves.

Conventional chemotherapy and radiotherapy strive to cause enough cell damage that the process of apoptosis, or programmed cell death, is triggered in cancerous cells. However, sometimes the damage is not enough and the cancerous cells can repair themselves and live on. Scientists developed tiny DNA fragments called Dbaits that mimic the broken ends of the long molecule. The cancer cells are tricked into believing they are more damaged than they really are, triggering apoptosis.

In laboratory mice, researchers were able to destroy 75% to 100% of tumors injected with Dbaits plus radiotherapy, compared to 30% to 50% using only radiotherapy. Dbaits also have the advantage of requiring lesser doses of radiation, which often damages surrounding healthy tissue as well as cancerous cells.

These results were published in a recent issue of Clinical Cancer Research.

Source: Yahoo!

"Astonishing Richness" Found in Polar Sea Life

Researchers working on the Census of Marine Life project have documented 7500 species living in the Antarctic as well as 5500 in the Arctic, hundreds of which may be new to science.

The census revealed an "astonishing richness" of species comparable to tropical environments in polar areas that were formerly believed to have less biodiversity. The study also revealed dozens of species common to both areas, leaving researchers unable to explain the commonalities in environments separated by 7000 miles of warmer oceans. As many as 235 distinct species were found common to both polar regions, including five whale species, six sea bird species and over 100 species of crustaceans.

Most of the species discovered were simple invertebrates, some living at ocean depths of up to 9800 feet. The ten-year project involves 500 polar scientists from 25 different countries supported by governments and conservation societies.

These results were announced February 15th by the Census of Marine Life, which is scheduled for final publication in 2010.

Source: Yahoo!

Comet Lulin Makes Closest Approach to Earth

A comet discovered two years ago by a Chinese teenager will make its first and only closest approach to Earth on Tuesday, February 24th.

Named after a Chinese observatory, Comet Lulin was first spotted in July 2007 by 17-year-old Quanzhi Ye. It is remarkable not only for its greenish color but because its discovery would not have been confirmed without the collaboration of Chinese and Taiwanese astronomers from the Lulin Observatory.

Comet Lulin originated on the outskirts of our solar system and will approach within 38 million miles of Earth, and its path around the Sun will provide enough energy to escape its orbit back into deep space, never to return. It has a rare greenish color due to the presence of the poison gas cyanogen and diatomic carbon, both of which glow green when illuminated by sunlight. Such gases are usually dispersed by solar energy on other comets but are present on Comet Lulin because this is its first approach to the Sun.

These results were announced on February 4th by NASA.

Source: Yahoo!

Elephants in Estrus Emit Low-Frequency Seismic Calls

Researchers at the Stanford University School of Medicine have discovered that female elephants in estrus can issue a low-frequency seismic call that travels through the soil.

In addition to their audible sounds, female elephants also produce low-frequency calls that can travel up to several kilometers through surface soils. Elephants have two systems that are highly developed for detecting such sounds: bone conduction, in which the low-frequency signals are detected by the bones in the feet and travel internally to the middle ear; and somatosensory reception, in which specialized nerve cells in the feet send signals directly to the brain.

Bull elephants can detect these low-frequency signals by using their feet and placing their trunks to the ground. Experiments showed that elephants placed their bodies perpendicular to the direction of the sound, creating the maximum distance between detection points to distinguish the source. Placing the trunk to the ground allows another detection point, allowing the elephant to triangulate the origin of the sound.

Seismic communication has been found to be used in some insect species but this is the first evidence for its application in mammals. Humans also possess both methods of sound detection, although our ability to use vibrations for communication is much less developed.

These results were originally announced in 2007 by the Stanford University School of Medicine.

Source: ScienceDaily

Map of Neanderthal Genome Completed

Scientists at the Max Planck Institute for Evolutionary Anthropology have completed their first draft of a map of the complete Neanderthal genome.

DNA fragments from three Croatian fossils were used to sequence three billion base pairs and map out more than 60% of the Neanderthal genome. Knowing the Neanderthal genome will help in analyzing our own genome and comparing what elements may have allowed Homo sapiens to succeed and thrive where Neanderthal failed. An initial analysis showed there was very little genetic contribution to our gene pool, indicating it was unlikely that there was much interbreeding between Neanderthal and modern man.

Modern man and Neanderthal shared a common ancestor some 300,000 years ago before the two evolutionary lines diverged. Neanderthals lived in Europe, Central Asia and the Middle East before disappearing completely about 28,000 years ago. The reasons for their disappearance are highly contested, as evidence shows they did coexist for some time along with Homo sapiens.

These results were announced on February 12th by the Max Planck Institute.

Source: Yahoo!

Energetic Gamma-Ray Bursts Detected from Neutron Star

Astronomers at Pennsylvania State University have detected and continue to record frequent and highly energetic x-ray and gamma ray blasts from a neutron star 30,000 light years away.

Using NASA's Swift X-Ray Telescope (XRT) and Fermi Gamma-Ray Space Telescope, astronomers have been tracking the known x-ray source cataloged as SGR J1550-5418 for more than two years. Last October, the object began a series of modest eruptions before settling down, only to roar back to life on January 22nd with even greater intensity. More than a hundred flares were detected in a space of only 20 minutes, with each flare emitting more energy than the Sun does in 20 years.

Neutron stars are collapsed stars containing the mass of the Sun compacted into a superdense sphere only about 12 miles in diameter. This object is a neutron star known as a magnetar, a subgroup known to have intense magnetic fields 1000 times stronger than normal, the strongest known magnetic fields in the universe. Because of its recent gamma-ray activity, this object is also classified as a soft-gamma-ray repeater, only the sixth such object known.

SGR J1550-5418 is spinning at a rate of one revolution every 2.07 seconds, making it the fastest-spinning magnetar yet found. In 2004, an intense burst from another soft-gamma-ray repeater had a measurable effect on Earth's upper atmosphere from 50,000 light years away.

These results were released on February 10th by NASA's Goddard Space Flight Center.

Source: ScienceDaily

Cache of Ice Age Fossils Discovered in Los Angeles

Scientists at the Page Museum have discovered the largest cache of Ice Age fossils extracted from the La Brea Tar Pits since their original excavations over a century ago.

Among the discoveries are the preserved skeletal remains of a near-complete Colombian mammoth, an American lion, saber-toothed cats, dire wolves, bison, horses, teratorn, coyotes and ground sloths as well as numerous smaller animals such as ancient turtles, small mammals, snails and insects. All the remains were found embedded in the asphalt of Rancho La Brea, and this find alone is expected to double the Ice Age collection of the Page Museum.

Paleontologists initially discovered 16 deposits during a dig in 2006 for the construction of an underground parking facility. Instead of being excavated on-site, because of construction deadlines the finds were boxed into 23 large separate containers and carefully removed, thus naming the discovery "Project 23." Scientists have been excavating the contents of the containers in the laboratory ever since.

These results were announced on February 18th by the Page Museum.

Source: Yahoo!

Large Cache of Mummies Discovered in Egyptian Tomb

Archaeologists from Egypt's Supreme Council of Antiquities announced the discovery of about two dozen mummies while unearthing a 2600-year-old tomb near Cairo.

The discoveries are part of a vast necropolis of Saqqara, south of Cairo, and is believed to be a storehouse for mummies dating back to 640 B.C. A total of 22 mummies were found stacked in the walls of a 36-foot deep shaft along with eight wooden sarcophagi, which are each believed to hold individual mummies themselves. Most of the mummies are poorly preserved and unidentified, and the reason for their storage here is unknown.

Saqqara has been under excavation for 150 years, with discoveries dating back more than 4300 years to the Old Kingdom as well as finds as recent as the Roman era. These mummies have been dated to the 26th Dynasty, which was Egypt's last independent kingdom before it was overthrown and ruled by foreign powers.

Egyptologists estimate that only about 30% of Egypt's monuments and archaeological finds have been uncovered, with the rest still buried at sites such as Saqqara.

These findings were announced February 8th by the Supreme Council of the Antiquties.

Source: Yahoo!

New Microscopy Method Provides Increased Resolution

Scientists at the Howard Hughes Medical Institute's Janelia Farm Research Campus have developed a new method that produces the best three-dimensional resolution ever with an optical microscope.

Beginning with the super-high resolution photoactivated localization microscopy (PALM), researchers added an interferometry method to create what they call interferometric photoactivated localization microscopy (iPALM). iPALM provides resolution down to about 10 to 20 nanometers, or roughly ten times the size of an average protein molecule. The new method also allows a three-dimensional measurement of image depth, an attribute difficult to obtain with optical microscopes.

The science of interferometry uses a light beam reflected off a surface and then compared with its original beam. As it is reflected, the light undergoes a small shift in wavelength that can be detected and measured for incredibly small differences in depth and distance, such as on the surface of a computer chip. PALM extends the resolution for conventional optical microscopes, which are inherently limited by the wavelength of visible light, and iPALM can theoretically achieve resolutions on the subatomic scale.

iPALM uses a very modest amount of light, which is critical for some biological samples that could either be damaged by strong light or distorted by the need to use reflective dyes for optical measurements.

These results were published in the February 2nd issue of the Proceedings of the National Academy of Sciences.

Source: ScienceDaily

Targeted Nanospheres Used to Burn Away Melanoma Tumors

Researchers at the Department of Experimental Diagnostic Imaging at the University of Texas M.D. Anderson Cancer Center have developed a method to destroy melanoma using targeted gold nanospheres to burn away the tumor from the inside.

Injecting simple hollow gold nanospheres 40-50 nm in diameter causes them to accumulate in melanoma tumors because their small size allows them to penetrate the abnormally large pores of blood vessels that feed cancerous tumors. However, when filled with a peptide that binds to the melanocortin type 1 receptor abundant in melanoma cells, these nanoparticles are actively drawn into the cells via the cell membrane.

Once these nanoparticles are in place, the tumor is subjected to a process called photothermal ablation. A dose of near-infrared light is applied to the cancer, which penetrates deeper into tissue than visible or ultraviolet light. The energy is absorbed by the nanoparticles, causing them to heat up and destroy the surrounding tissue. At a dose merely 12% of the dose required without the nanoparticles, cancerous tumors are highly targeted and healthy tissue is spared.

The use of elemental gold has a long history of medical applications as it is safe and largely nonreactive to organic tissues. Experiments have been successful in laboratory and mouse models but still await human trials.

These results were published in the February 1st issue of Clinical Cancer Research.

Source: ScienceDaily; Photo: M.D. Anderson

New Bird Species Discovered in China

Ornithologists from Guangxi University have discovered a new bird species in southwest China near its border with Vietnam.

Named Stachyris nonggangensis, or the Nonggang babbler after the wildlife reserve at which it was discovered, this bird is closely related to the known sooty babbler also of the Guangxi province of China. It seems to prefer running to flying, foraging for insects on the forest floor, in contrast to other babbler species that seldom come to the ground.

The new babbler species lives in what is known as the Chinese Mountains Endemic Bird Area, one of the most biodiverse tropical regions in the world. The discovery of a new species is significant as it may indicate many more as-yet unknown species in this part of the world that is quickly being deforested for lumber and charcoal.

These results were published in a recent edition of The Auk.

Source: ScienceDaily

Largest Snake Fossil Discovered in Colombia

Scientists from an international team lead by the University of Florida's Florida Museum of Natural History have discovered fossil remains of the largest snake species ever recorded.

Named Titanoboa cerrejonensis, the ancient snake measured 42 to 45 feet long and weighed an estimated 2500 pounds. It lived between 58 million and 60 million years ago and could have easily swallowed ancient crocodiles whole. The fossils were discovered on a dig in a Cerrejón coal mine in Colombia in 2007, and the find breaks the record by 11 feet for the longest snake ever found, a record previously held by fossil remains found in Egypt.

Paleontologists previously believed that snakes had a maximum on how long they could grow, a value somewhat less than 40 feet. The size of a snake is a direct indicator of its environment, as modern snake's sizes are a function of how warm their environment is. A snake as large at Titanoboa indicates that prehistoric South America was as much as 10 degrees warmer than it is today.

Previously, scientists had found no fossils from any vertebrate species that lived between 65 million and 55 million years ago in South America, a period of time just after the extinction of the dinosaurs. Along with about 180 fossil pieces were remains of extinct crocodile and turtle species, likely eaten by Titanoboa.

These results were published in the February 5th issue of Nature.

Source: ScienceDaily

Orbiting Telescope Detects Smallest Exoplanet

An orbiting telescope run by the French space agency Centre National d’Etudes Spatiales (CNES) has detected the smallest exoplanet yet discovered, a planet only about twice the size of Earth.

The Corot telescope discovered the planet using a technique known as the transit method, by which the light of the star dims slightly as the planet crosses its visible path. Designated Corot-Exo-7b, the planet orbits its star once every 20 hours and because of its proximity to its sun, its surface temperature lies between 1000°C and 1500°C, far too inhospitable to support life. Another planet also orbits the same star, one larger and more similar to Neptune.

About 330 exoplanets have been identified so far, with most belonging to the type known as gas giants more similar to Jupiter or Neptune than "rocky" planets such as Earth or Mars. Most exoplanets are discovered using what is known as the radial velocity method, which is a slight but detectable wobbling of the star due to an orbiting planet's own gravity.

These results were announced February 3rd on the European Space Ageny (ESA) website.

Source: BBC News

White-Nose Syndrome Killing Bats in Northeastern U.S.

Biologists at the U.S. Fish and Wildlife Service have identified a mysterious white fungus that is responsible for devastating bat populations in the northeastern United States.

First identified two years ago, scientists have isolated a white fungus that grows on the muzzle (hence the name "white-nose syndrome") and body of bats and thrives in the extreme cold and dry conditions of winter caves. The exact mechanism by which this fungus kills the bats is not yet understood, but the condition appears to have an 80% to 100% mortality rate. Some hibernacula (bat colonies) have lost as many as 90% of their numbers.

White-nose syndrome was first found in caves in upstate New York, Vermont, western Massachusetts and Connecticut but has spread this year to caves as far as New Jersey and Pennsylvania. Little brown bats are the most affected species, although the disease has also affected northern long-eared and small-footed bats, eastern pipistrelle bats as well as the Indiana bat, currently listed as an endangered species. Because female bats birth only one pup per year, this syndrome may have serious consequences to their overall population.

Bats play a crucial role in many ecosystems by keeping the insect population in check as well as providing pollination for some plants. The fungus is not believed to pose a health risk for humans but there is a fear that this syndrome could spread unchecked and spur an ecological crisis as local bat colonies disappear.

This news was released recently by the Northeast Region of the U.S. Fish and Wildlife Service.

Source: Yahoo!

New Form of Elemental Boron Discovered

Researchers at Stony Brook University have discovered a new phase of elemental boron, created in the laboratory under extremely high pressures.

The new phase of boron is stable at high temperatures and at pressures as great as 100,000 times atmospheric pressure. The atomic structure of this phase consists of two substructures stacked together, with a matrix of 12 spherical boron atoms that includes two-atom "dumbbell" pairs. The two substructures form ionic bonds, the first time this type of bond has been observed in structures consisting of only one element.

Developed independently in two different laboratories in 2004, scientists were unable to determine how or why this phase was created. Computational analysis using a specially developed algorithm allowed researchers to encode the crystal structure and allow the program to find the optimal arrangement, thus confirming the properties of the newly discovered material.

Three phases of boron were previously known, with some uncertainty about its naturally stable form. This fourth phase is not as hard as diamond but has better heat-resistant properties, which may lend itself to industrial applications.

This research was published online in the January 28th edition of Nature.

Source: New York Times

Ten New Amphibian Species Discovered in Colombia

Members of Conservation International discovered ten previously unknown species while on an expedition in the tropical mountains of Colombia.

Among the new species found were three glass frogs of the Nymphargus, Cochranella and Centrolene genera, so called because their internal organs are visible through their translucent skin; three poison dart frogs of the Colostethus, Ranitomeya and Anomaloglossus genera, whose natural toxins present on their skin make them poisonous; one harlequin frog of the genus Atelopus; two different types of Pristimantis rain frogs; and one Bolitoglossa salamander species. Colombia is recognized as having one of the most diverse amphibian communities in the world, with 754 currently known species.

The expedition was part of the group's Rapid Assessment Program (RAP) and targeted the Darien region of Colombia near the Panama border, which includes the mountainous Tacarcuna area. Herpetologists from Conservation International led the expedition, which also included ornithologists from Colombia's Ecotrópico Foundation. Over a period of three weeks, the group cataloged about 60 species of amphibians, 20 species of reptiles and almost 120 species of birds, many found nowhere else.

Amphibians are considered "indicator species" because their permeable skin exposes them directly to the environment, and thus these animals are affected by changes or contaminants in that environment before other more robust species. Amphibians are also extremely sensitive to variations in temperature and moisture brought about by changes in climate.

These results were announced February 2nd on Conservation International.

Source: Yahoo!

Turtle Fossil Points to Warm Arctic Past

Geologists from the University of Rochester discovered a warm-weather turtle fossil in the Canadian Arctic that suggests once temperate or even subtropical temperatures at the poles.

Setting out to study the paleomagnetism of the region, the turtle was uncovered almost by accident in an area known to be rich with fossils. A previously unknown species, the fossil resembles modern tropical Mongolian freshwater turtles and suggests a much warmer climate than the current frigid temperatures in the Arctic. In conjunction with the Royal Tyrrell Museum of Canada, the turtle species was named Aurorachelys, or aurora turtle.

Animals were previously thought to migrate between Asia and North America in the Cretaceous period via a former land bridge that existed around the Alaska region. This fossil evidence points to a previous warm Arctic freshwater sea that existed about 90 million years ago, through which species such as this turtle could have migrated directly across the pole.

This warming is believed to be due to ancient volcanic activity pumping massive amounts of carbon dioxide into the atmosphere, creating a "super-greenhouse effect" with a warm Arctic sea free of ice.

These results were published in the February issue of Geology.

Source: ScienceDaily

Single Gene Allows Bacteria to Migrate between Hosts

Scientists at the University of Wisconsin-Madison have discovered that a single gene allows a bacteria to migrate to new host species.

Both marine species bobtail squid and pinecone fish use bacteria-based bioluminescence as part of their camouflage and hunting techniques. The same species of bacteria, Vibrio fischeri, was found in both marine animals with one exception: the difference of a single additional gene in the variety present in the squid. This extra gene serves as a regulatory agent that allows the bacteria to colonize the new host species.

Virtually every animal known (including humans) has a variety of microorganisms specifically associated with that species, and microbial life crossing species to infect a new host is very rare. Scientists previously believed this rarity was due to bacteria requiring a wide set of new genes to successfully infect a different animal.

This research reveals that a single regulatory gene is all that is necessary to migrate to a new host species. Knowledge of this process may assist in the development of new drugs or therapies as a single gene is easier to target for the prevention or treatment of infection.

These results were published in the February 1st issue of Nature.

Source: ScienceDaily

Blue Light Destroys MRSA

Researchers at the New York Institute of Technology have discovered that a certain wavelength of blue light destroys the virulent antibiotic-resistant strain of the Staph bacteria known as MRSA.

In a process known as photo-irradiation, two common strains of methicillin-resistant Staphylococcus aureus (MRSA) were exposed to various doses of 470 nm blue light, a wavelength that does not emit ultraviolet radiation. The team found that the greater the dose of light used, the more microorganisms were killed. Up to 90.4% in colonies of the MRSA strains US-300 and IS-853 were destroyed using this method.

The precise method by which this process works is not fully understood but it is believed the DNA of the bacteria absorbs the energy of these specific wavelengths, causing irreparable damage and eventual cell death. Researchers have long known the bactericidal effects of 400-nm light and ultraviolet radiation, with research as far back as 1930. Blue light of 415 nm has been used to treat acne cases by destroying Propionibacterium acne, and the infectious Pseudomonas aeruginosa is killed by light with a wavelength of 405 nm.

MRSA poses an increasing health threat, as approximately 40% to 50% of all staphylococcal strains have developed resistance to modern antibiotics such as methicillin. Less than 5% of staphylococcal strains are currently susceptible to penicillin treatments. The use of blue light in the laboratory suggests it may be effective for the treatment of cutaneous and subcutaneous infections without promoting further resistance to antibiotics.

These results are scheduled to appear in the April issue of Photomedicine and Laser Surgery.

Source: ScienceDaily; Photo: Wikipedia

Serotonin Causes Locusts to Swarm

Scientists at the University of Cambridge have found that a sharp increase in serotonin levels in locusts is the chemical trigger that causes them to swarm.

Normally a solitary insect, locusts produce more serotonin when circumstances such as drought force many of them together, such as at a common remaining food source. This combined sight, smell and touch of similar insects induces the production of serotonin, and at levels as much as three times normal they operate as pack animals in devastating swarms that affect up to 20% of the Earth's land.

Serotonin is a brain chemical that has been linked to libido, mood, appetite, sleep and memory in humans. Researchers found they could induce this swarming behavior in locusts by injecting them with serotonin, as well as inhibit this behavior by using a serotonin blocker. Knowledge of how chemicals such as serotonin affect insects could lead to better methods to prevent ravaging swarms before they develop.

These results were published in the January 30th edition of Science.

Source: Yahoo!

First Astronomical Observation of Exoplanet Weather

Researchers at the University of California, Santa Cruz have observed changing weather patterns for the first time on a planet outside our own solar system.

Using NASA's Spitzer Space Telescope, the scientists observed an extrasolar planet known as HD80606b, a giant planet four times as large as Jupiter that orbits a star some 200 light years distant. As the planet orbits close to its sun, the normal 980°F surface temperature quickly heats up to around 2240°F.

Temperatures were determined from infrared measurements of the planet, and the data was used to simulate realistic weather patterns using a computer model. The massive dose of radiation received from such a close encounter with its sun creates global storms and shockwaves throughout the atmosphere, including winds estimated at speeds of up to 5 km/sec.

Discovered in 2001, HD80606b has the most eccentric orbit of any planet yet identified, completing an elliptical comet-like orbit in only 111 days. It approaches more than ten times closer to its star than does the planet Mercury, and completes this close transit in less than 24 hours.

These results were published in the January 29th issue of Nature.

Source: Yahoo!; Photo: ScienceDaily

Honey Bees Can Recognize Simple Numbers

A team of researchers from the Australian National University and Würzburg University have shown that honey bees can distinguish between simple numbers at a glance.

The experiment consisted of a tunnel with various branch points, each branch marked with a collection of dots and only one sequence of dots leading to a reward. To reach the reward, honey bees had to navigate through the choices corresponding to a consistent number of dots. After taking time to initially examine the dots, the honey bees reliably and repeatedly followed the correct sequence in subsequent runs, even when the nondescript dots were replaced with different colors, shapes or patterns.

The bees could easily distinguish and make choices based on one, two and three items, and could even learn to recognize four items with a little practice, but they could not reliably tell the difference among groups of items greater than four. This is a process known as subitizing, or responding rapidly to a small collection of items, and demonstrates at least a basic understanding of numbers.

A great deal of evidence exists for this counting ability among vertebrates such as birds, monkeys or dolphins but this is the first evidence for a similar ability in insects. Such an ability may prove useful for honey bees to recall a path traveled in their search for food, which in some documented cases can take them as much as 11 kilometers away from their hive.

These results were published January 29th in the journal Public Library of Science.

Source: ScienceDaily

Language Study Traces Pacific Settlement

Scientists at the University of Auckland have completed a human language study that traces the settlement of the South Pacific to its origins on the island of Taiwan.

Using a computer to analyze 400 Austronesian languages spread across the Pacific islands, the historical trace and progress of how prehistoric cultures settled these locations can be determined. They found the ancestors of modern Austronesians originated in Taiwan about 5200 years ago, entered the Philippines about a thousand years later and from there rapidly expanded throughout Polynesia as far as Fiji, Samoa and Tonga. After another pause of roughly a thousand years, settlement expanded again to areas as far away as Hawaii and Easter Island.

The "family tree" of Pacific languages was constructed by a comparative analysis of simple vocabulary such as words for animals, numbers, colors and simple verbs. The Austronesian group is one of the largest families of languages in the world, containing more than 1200 languages spread across the Pacific.

These results were published in a recent edition of Science.

Source: ScienceDaily

Miniature Boat Powered by Surface Tension

Engineers at the University of Pittsburgh have developed a miniature boat that propels itself across water with no moving parts using nothing but a disruption of the surface tension.

Inspired by how beetle larvae move across the water, the boat uses a similar process for its own propulsion without paddles, sails or motors. With the surface tension of water pulling a floating object equally on all sides, an electric pulse disrupts the surface tension to the rear with the remaining surface tension pulling the boat in the opposite direction. Pyrrhalta beetle larvae accomplish the same by arching their back downward as they rest on top of the water.

Experiments moved a 2-cm "mini-boat" across the water's surface at approximately 4 mm per second, with a second electrode mounted at the rear acting as a rudder. This method of propulsion provides an efficient and low-maintenance method for small automated tools and robots that monitor water quality in reservoirs and other bodies of water. The craft can be powered either by on-board batteries or solar power.

These results were presented on January 26th at the Institute of Electrical and Electronics Engineers' 2009 Micro Electro Mechanical Systems (MEMS) conference in Sorrento, Italy.

Source: ScienceDaily

Brain Cells Discovered Acting as Short-Term Memory Buffer

Researchers at the UT Southwestern Medical Center have discovered that some cells in the front part of the brain can hold temporary short-term memory information.

Single cells in the most highly evolved part of the brain can hold nonpermanent moment-to-moment data in a process called metabotropic glutamate transmission. This process uses calcium to start a signal cascade to hold a memory trace within individual neurons for as long as a minute, and is responsible for the temporary memory used in multitasking or playing a card game.

Traditional long-term memory involves a slow-moving protein activating ion channels among cellular networks to strengthen their connections and establish a permanent record, a process too slow to record or buffer rapidly incoming messages from the senses. This research has implications for addiction, attention disorders and stress-related memory loss.

Scientists experimented with mouse models using the neurochemical dopamine, a substance necessary for proper focus and fast, short-term memory. Drug and alcohol abuse involves substances that flood the brain with dopamine, and researchers found that repeated exposure to high levels of dopamine reduces the memory trace activation ability in these specialized brain cells.

This research was published in the Febrary issue of Nature Neuroscience.

Source: ScienceDaily