Πέμπτη 27 Φεβρουαρίου 2014

ScienceDaily: Top Environment News

ScienceDaily: Top Environment News


Water filter from the sapwood in pine tree branches

Posted: 26 Feb 2014 02:45 PM PST

If you've run out of drinking water during a lakeside camping trip, there's a simple solution: Break off a branch from the nearest pine tree, peel away the bark, and slowly pour lake water through the stick. The improvised filter should trap any bacteria, producing fresh, uncontaminated water. In fact, scientists have discovered that this low-tech filtration system can produce up to four liters of drinking water a day -- enough to quench the thirst of a typical person. The researchers demonstrate that a small piece of sapwood can filter out more than 99 percent of the bacteria E. coli from water.

Waterbirds' hunt aided by specialized tail: Swimming birds evolved rudder-like tail to dive for food

Posted: 26 Feb 2014 02:45 PM PST

The convergent evolution of tail shapes in diving birds may be driven by foraging style. Birds use their wings and specialized tail to maneuver through the air while flying. It turns out that the purpose of a bird's tail may have also aided in their diversification by allowing them to use a greater variety of foraging strategies. To better understand the relationship between bird tail shape and foraging strategy, researchers examined the tail skeletal structure of over 50 species of waterbirds, like storks, pelicans, and penguins, and shorebirds, like gulls and puffins. They first categorized each species by foraging strategy, such as aerial, terrestrial, and pursuit diving, and then compared the shape and structure of different tails.

Impact on mummy skull suggests murder

Posted: 26 Feb 2014 02:45 PM PST

Blunt force trauma to the skull of a mummy with signs of Chagas disease may support homicide as cause of death, which is similar to previously described South American mummies. Radiocarbon dated to around 1450 -- 1640 AD, skeletal examination indicated that the mummy was likely 20-25 years old at the time of her death, and her skull exhibits typical Incan-type skull formations.

Cows are smarter when raised in pairs: Evidence practice of housing calves alone linked to learning difficulties

Posted: 26 Feb 2014 02:45 PM PST

Cows learn better when housed together, which may help them adjust faster to complex new feeding and milking technologies on the modern farm, a new study finds. Dairy calves become better at learning when a "buddy system" is in place. The study also provides the first evidence that the standard practice of individually housing calves is associated with certain learning difficulties.

Climate change: No warming hiatus for extreme hot temperatures

Posted: 26 Feb 2014 01:53 PM PST

While there are claims that there has been a hiatus in global average temperatures, no such hiatus has occurred at the extreme end of the temperature spectrum. New research shows extremely hot temperatures over land have dramatically and unequivocally increased in number and area despite claims that the rise in global average temperatures has slowed over the past 10 to 20 years.

Antarctic circumpolar current carries 20 percent more water than previous estimates

Posted: 26 Feb 2014 01:51 PM PST

By analyzing four years of continuous measurements of the Antarctic Circumpolar Current at Drake Passage, the narrowest point in the Southern Ocean, oceanographers have concluded that the current carries 20 percent more water than previous estimates. They also found that the current remains strong all the way to the seafloor.

Phony honey a sweet deal for counterfeiters, bad for consumers

Posted: 26 Feb 2014 01:51 PM PST

Consumers buying honey might not be getting what they pay for according to one of the world's leading honey experts, who is supporting a U.S. Senate bill that would, if passed, put more stringent requirements on the federal government to ensure the origin of imported honey and compel sellers to label it accurately.

Still-fresh remnants of Exxon Valdez oil 25 years after oil spill, found protected by boulders

Posted: 26 Feb 2014 12:56 PM PST

Twenty-five years after the infamous Exxon Valdez oil spill in Prince William Sound, beaches on the Alaska Peninsula hundreds of kilometers from the incident still harbor small hidden pockets of surprisingly unchanged oil, according to new research.

Finding a few foes among billions of cellular friends

Posted: 26 Feb 2014 10:30 AM PST

Beating cancer is all about early detection, and new research is another step forward in catching the disease early. A team of chemists is reporting a new way to detect just a handful of lurking tumor cells, which can be outnumbered a billion to one in the bloodstream by healthy cells. The researchers have constructed an ultrasensitive nanoprobe that can electrochemically sense as few as four circulating tumor cells, and it doesn't require any enzymes to produce a detectable signal.

Nanoscale freezing leads to better imaging

Posted: 26 Feb 2014 10:30 AM PST

It's an odd twist. For scientists to determine if a cell is functioning properly, they must destroy it. This is what happens in X-ray fluorescence microscopy when biological specimens are exposed to ionizing radiation, which provides images with a level of detail that conventional microscopes just can't match. This exposure can change what is being imaged in profound ways, possibly giving false accounts of how the cell actually works. To address this issue, researchers created a new probe that freezes cells to "see" at greater detail without damaging the sample.

Predictive fitness model for influenza: Physics, computer science help find clues on flu evolution

Posted: 26 Feb 2014 10:29 AM PST

A new model to successfully predict the evolution of the influenza virus from one year to the next has been created by researchers. This advance in our understanding of influenza suggests a new, systematic way to select influenza vaccine strains. The flu is one of the major infectious diseases in humans. Seasonal strains of the influenza A virus account for about half a million deaths per year. Because influenza is a fast-evolving pathogen, the selection of optimal vaccines is a challenging global health issue. The scientists used ideas from physics and computer science in their approach to finding clues about the predictable versus random part of the flu evolution.

Pine forest particles appear seemingly out of thin air, influence climate

Posted: 26 Feb 2014 10:29 AM PST

Pine forests are especially magical places for atmospheric chemists. Coniferous trees give off pine-scented vapors that form particles, very quickly and seemingly out of nowhere. New research elucidates the process by which gas wafting from coniferous trees creates particles that can reflect sunlight or promote formation of clouds.

Shingles: A common and painful virus

Posted: 26 Feb 2014 10:27 AM PST

Shingles is a painful viral infection that affects almost one million people worldwide and 30 percent of Americans every year. Known as herpes zoster, it's caused by the same virus that causes chicken pox, the varicella-zoster virus. The outbreak occurs mostly in people older than 50 because the virus can lay dormant in the nerve tissue of the body for many years then become activated and cause shingles later in life. A new article gives advice and guidance for those at risk.

Join the crowd: Digitize biodiversity research specimens

Posted: 26 Feb 2014 10:27 AM PST

A crowdsourcing project aims to enable transcription of specimen labels and ledgers from the world's 3 billion biodiversity research specimens.

New target for dengue virus vaccine found

Posted: 26 Feb 2014 09:53 AM PST

Using an experimental technique new to the dengue field, researchers showed that a molecular hinge where two regions of a protein connect is where natural human antibodies attach to dengue type-3 to disable it. The finding shows that most human antibodies that neutralize the virus bind to this hinge. It's the first study to demonstrate how these binding sites can be genetically exchanged without disrupting the integrity of the virus.

Climate change puts wheat crops at risk of disease

Posted: 26 Feb 2014 09:52 AM PST

There is a risk that severity of epidemics of some wheat diseases may increase within the next ten to twenty years due to the impacts of climate change according to a study by international researchers. The researchers carried out a survey in China to establish a link between weather and the severity of epidemics of fusarium ear blight on the wheat crops. This weather-based model was then used to predict the impact on severity of the disease of future weather scenarios for the period from 2020 to 2050.

Moths trapped with plant-produced sex pheromone

Posted: 26 Feb 2014 09:52 AM PST

By engineering plants that emitted sex pheromones that mimic those naturally produced by two species of moths, researchers have demonstrated that an effective, environmentally friendly, plant-based method of insect control is possible. While a proof-of-concept experiment, engineering plants to be insect pheromone-producing factories creates an environmentally friendly alternative to pesticides as well as an easier and less expensive method of synthesizing insect pheromones

Optical 'nanocavity' to boost light absorption in semiconductors; improve solar cells, cameras and more

Posted: 26 Feb 2014 08:09 AM PST

Scientists are developing an optical 'nanocavity' that boosts the amount of light that ultrathin semiconductors absorb. The advancement could lead to: more powerful photovoltaic cells; faster video cameras; and it could be useful for splitting water using energy from light, which could aid in the development of hydrogen fuel.

Decline of bronze age 'megacities' linked to climate change

Posted: 26 Feb 2014 08:08 AM PST

Scientists have demonstrated that an abrupt weakening of the summer monsoon affected northwest India 4,100 years ago. The resulting drought coincided with the beginning of the decline of the metropolis-building Indus Civilization, which spanned present-day Pakistan and India, suggesting that climate change could be why many of the major cities of the civilization were abandoned.

Thirty-nine new species of endemic cockroach discovered in the southwestern US and Mexico

Posted: 26 Feb 2014 08:08 AM PST

An American systematist has described 39 new species of endemic desert cockroaches from the southwestern US and Mexico. The roaches belong to the genus Arenivaga, in one of the lesser known families of cockroaches, which previously held nine species.

Replicating motions of the heart: Artificial muscles that do the twist set the stage for soft robotics

Posted: 26 Feb 2014 08:08 AM PST

Researchers have developed a low-cost, programmable soft actuated material that they used to replicate the complex motion of the heart, along with a matching 3-D computer model. The advance sets the stage for new possibilities in the emerging field of soft robotics.

Superabsorbing design may lower manufacturing cost of thin film solar cells

Posted: 26 Feb 2014 08:08 AM PST

Researchers have developed a 'superabsorbing' design that may significantly improve the light absorption efficiency of thin film solar cells and drive down manufacturing costs.

Research and applications of iron oxide nanoparticles explored

Posted: 26 Feb 2014 08:07 AM PST

A scientist spent thirty years investigating how craftsman were able to render the beautiful red colors in Bizen and Arita pottery. This research revealed the important role of iron oxide particles for producing the colors. Now he is working on innovative applications of nanometer scale iron oxide materials produced by 'iron-oxidizing bacteria', having made the transition from fine ceramics and Bizen stoneware to fuel cells and biotechnology.

Algae's viability as a biofuel advanced

Posted: 26 Feb 2014 07:18 AM PST

Lab success doesn't always translate to real-world success. Scientists have now, however, invented a new technology that increases the odds of helping algae-based biofuels cross that gap and come closer to reality.

Different eggs in adolescent girls, adult women

Posted: 26 Feb 2014 07:18 AM PST

Are the eggs produced by adolescent girls the same as the ones produced by adult women? A recent study shows compelling evidence that there are two completely distinct types of eggs in the mammalian ovary -- 'the first wave' and 'the adult wave.' The first wave of eggs, which starts immediately after birth, contributes to the onset of puberty and provides fertilizable eggs into the transition from adolescence to adulthood. In contrast, the adult wave remains in a state of dormancy until activated during the adult life and then provides eggs throughout the entire reproductive lifespan.

Where have all the codfish gone? Research suggests food source loss has contributed

Posted: 26 Feb 2014 06:52 AM PST

The mega-decline in cod and other fisheries across the North Atlantic Ocean threatens the livelihood of fishermen and communities in New England and Atlantic Canada. One suspect in the disappearance of cod and other groundfish is the food source for their young: a planktonic copepod crustacean. The first transcriptome for the key North Atlantic copepod Calanus finmarchicus has been published; scientists will use it to decode the genetic instructions that are resulting in population changes.

Scientists blend synthetic air to measure climate change

Posted: 26 Feb 2014 06:52 AM PST

Scientists have produced a synthetic air reference standard which can be used to accurately measure levels of carbon dioxide and methane in the atmosphere. This will greatly help scientists contribute to our understanding of climate change.

Whales, ships more common through Bering Strait

Posted: 26 Feb 2014 06:52 AM PST

The Arctic is home to a growing number of whales and ships, and to populations of sub-Arctic whales that are expanding their territory into newly ice-free Arctic waters. A three-year survey of whales in the Bering Strait reveals that many species of whales are using the narrow waterway, while shipping and commercial traffic also increase.

Fish tacos: A nutritional lunch

Posted: 26 Feb 2014 06:48 AM PST

An aquaponics project studying the interdependence of fish and plants winds up rolled in tortillas and served with organic coleslaw.

Offshore wind farms could tame hurricanes before they reach land

Posted: 26 Feb 2014 04:50 AM PST

Computer simulations have shown that offshore wind farms with thousands of wind turbines could have sapped the power of three real-life hurricanes, significantly decreasing their winds and accompanying storm surge, and possibly preventing billions of dollars in damages. In the case of Hurricane Katrina, the computer model revealed that an array of 78,000 wind turbines off the coast of New Orleans would have significantly weakened the hurricane well before it made landfall.

Candelabra found in Ibiza waters offers clues about medieval navigation routes

Posted: 26 Feb 2014 04:49 AM PST

The history of medieval navigation on the Iberian peninsula is a great mystery. In the 1970s, a recreational diver found a bronze candelabra in Ibiza. It is a unique piece from the 10th century which could provide clues on sea routes in the period.

Did five years of drought lead to two years of revolution in Syria?

Posted: 26 Feb 2014 04:49 AM PST

Negotiators in Geneva might not have brought the conflict in Syria to an end last week, but new research explains how the 2006–10 drought contributed to its start.

Climate change causes high but predictable extinction risks

Posted: 26 Feb 2014 04:45 AM PST

Judging the effects of climate change on extinction may be easier than previously thought, according to a new article. Although widely used assessments of threatened species, such as the IUCN Red List, were not developed with the effects of climate change in mind, a study of 36 amphibian and reptile species endemic to the US has concluded that climate change may not be fundamentally different from other extinction threats in terms of identifying species in danger of extinction.

Mass strandings of marine mammals blamed on toxic algae: Clues unearthed in ancient whale graveyard

Posted: 25 Feb 2014 04:34 PM PST

Modern whale strandings can be investigated and their causes identified. Events that happened millions of years ago, however, are far harder to analyze -- frequently leaving their cause a mystery. Scientists examined a large fossil site in the Atacama Desert of Northern Chile -- the first definitive example of repeated mass strandings of marine mammals in the fossil record. It reflected four distinct strandings over time, indicating a repeated and similar cause: toxic algae.

Skin cancer risk may have driven evolution of black skin

Posted: 25 Feb 2014 04:34 PM PST

Early humans may have evolved black skin to protect against a very high risk of dying from ultraviolet light-induced skin cancer, a new analysis concludes. Skin cancer has usually been rejected as the most likely selective pressure for the development of black skin because of a belief that it is only rarely fatal at ages young enough to affect reproduction. But a new paper cites evidence that black people with albinism from parts of Africa with the highest UV radiation exposure, and where humans first evolved, almost all die of skin cancer at a young age.

'Team of rivals' approach works for sparrows defending territories

Posted: 25 Feb 2014 04:34 PM PST

A new study of territorial songs used by chipping sparrows to defend their turf reveals that males sometimes will form a "dear enemy" alliance with a weaker neighbor to prevent a stronger rival from moving in. For the first time findings demonstrate the birds' use of a stereotyped, specialized signal, in this case chipping sparrow trills, to establish brief periods of cooperation among neighbor birds who are otherwise rivals.

Study of jaw mechanics sheds new light on early tetrapod feeding habits

Posted: 25 Feb 2014 04:32 PM PST

A study of the jaws of one of the earliest known limbed vertebrates shows the species still fed underwater, not on land. Tetrapods -- the four-legged limbed vertebrates -- evolved from fish and include today's amphibians, reptiles, birds and mammals. Acanthostega is regarded as one of the best known early tetrapods, and has played a key role in debates about tetrapod origins since spectacular new specimens were discovered in Greenland in 1987. Dating back to some 360 million years ago (end of the Devonian period); it has often been seen as a near-perfect fish-tetrapod intermediate.

Continuous handling of receipts linked to higher urine BPA levels

Posted: 25 Feb 2014 01:27 PM PST

Study participants who handled receipts printed on thermal paper continuously for two hours without gloves had an increase in urine bisphenol A (BPA) concentrations compared to when they wore gloves, according to a study. Human exposure to bisphenol A (BPA) has been associated with adverse health outcomes, including reproductive function in adults and neurodevelopment in children exposed shortly before or after birth.

MMR vaccine linked to lower rate of infection-related hospital admissions

Posted: 25 Feb 2014 01:27 PM PST

In a nationwide group of Danish children, receipt of the live measles, mumps, and rubella (MMR) vaccine on schedule after vaccination for other common infections was associated with a lower rate of hospital admissions for any infections, but particularly for lower respiratory tract infections, according to a study. Childhood vaccines are recommended worldwide, based on their protective effect against the targeted diseases.

New clues found to preventing lung transplant rejection

Posted: 25 Feb 2014 01:25 PM PST

Broadly suppressing the immune system after lung transplantation may inadvertently encourage organ rejection, according to a new study in mice. Organ transplant patients routinely receive drugs that stop their immune systems from attacking newly implanted hearts, livers, kidneys or lungs, which the body sees as foreign. In a surprising discovery, researchers found that newly transplanted lungs in mice were more likely to be rejected if key immune cells were missing, a situation that simulates what happens when patients take immunosuppressive drugs.

Ordinary conditioner removes head lice eggs as effectively as special products

Posted: 25 Feb 2014 11:39 AM PST

Some shampoos and conditioners that contain chemicals or special oils are marketed as nit-removal products for head lice eggs. However, new research shows that ordinary hair conditioner is just as effective. Eggs from head lice, also called nits, are incredibly difficult to remove. Female lice lay eggs directly onto strands of hair, and they cement them in place with a glue-like substance, making them hard to get rid of. In fact, the eggs are glued down so strongly that they will stay in place even after hair has been treated with pediculicides -- substances used to kill lice.

Nuclear stiffness keeps stem cells, cancer cells in place

Posted: 25 Feb 2014 11:39 AM PST

Adult stem cells and cancer cells have many things in common, including an ability to migrate through tiny gaps in tissue. Both types of cells also experience a trade-off when it comes to this ability; having a flexible nucleus makes migration easier but is worse at protecting the nucleus' DNA compared to a stiffer nucleus. Nuclear proteins that regulate nuclear stiffness are therefore thought to control processes as diverse as tissue repair and tumor growth.

Ecotoxicity: All clear for silver nanoparticles?

Posted: 25 Feb 2014 10:45 AM PST

It has long been known that, in the form of free ions, silver particles can be highly toxic to aquatic organisms. Yet to this day, there is a lack of detailed knowledge about the doses required to trigger a response and how the organisms deal with this kind of stress. In the past, silver mostly found its way into the environment in the vicinity of silver mines or via wastewater emanating from the photo industry. More recently, silver nanoparticles have become commonplace in many applications -- as ingredients in cosmetics, food packaging, disinfectants, and functional clothing. To learn more about the cellular processes that occur in the cells, scientists subjected algae to a range of silver concentrations.

Climate engineering: Minor potential, major risk of side-effects?

Posted: 25 Feb 2014 09:25 AM PST

Researchers have studied with computer simulations the long-term global consequences of several 'climate engineering' methods. They show that all the proposed methods would either be unable to significantly reduce global warming if CO2 emissions remain high, or they could not be stopped without causing dangerous climate disruption.

New neurons generated in brains, spinal cords of living adult mammals

Posted: 25 Feb 2014 09:25 AM PST

New nerve cells in the brains and spinal cords of living mammals have been created by researchers without the need for stem cell transplants to replenish lost cells. Although the research indicates it may someday be possible to regenerate neurons from the body's own cells to repair traumatic brain injury or spinal cord damage or to treat conditions such as Alzheimer's disease, the researchers stressed that it is too soon to know whether the neurons created in these initial studies resulted in any functional improvements, a goal for future research.

Byproducts of bacteria-causing gum disease incite oral cancer growth, study shows

Posted: 25 Feb 2014 09:25 AM PST

Researchers have discovered how byproducts in the form of small fatty acids from two bacteria prevalent in gum disease incite the growth of deadly Kaposi's sarcoma-related lesions and tumors in the mouth. High levels of these bacteria are found in the saliva of people with periodontal disease, and at lower levels in those with good oral health -- further evidence of the link between oral and overall physical health. The discovery could lead to early saliva testing for the bacteria, which, if found, could be treated and monitored for signs of cancer and before it develops into a malignancy, the researchers say.

Discovery of a 'conductor' in muscle development could impact on the treatment of muscular diseases

Posted: 25 Feb 2014 09:24 AM PST

A 'conductor' has been discovered in the development of muscle tissue. The discovery could have an important impact on the treatment of muscular diseases such as myopathies and muscular dystrophies. The fusion of myoblasts is a critical step in the formation of embryonic muscle fibers as it determines muscle size, among other things. This process is also important in adult life because muscle stem cells fuse with existing fibers to achieve muscle growth and help regenerate damaged muscles. However, until now, fusion remained a poorly understood step within the scientific community.

Horticulture: Multiple commercial uses of wireless sensor networks outlined in report

Posted: 25 Feb 2014 09:24 AM PST

A review examines three on-farm case studies of product development, deployment, and implementation of wireless sensor networks as a means to increase irrigation efficiency in commercial horticulture operations. The report focuses on the use of capacitance-based soil moisture sensors to both monitor and control irrigation events, describing the implementation and use of soil moisture-based irrigation hardware and software developed.

Horticulture: Sensor-based irrigation systems show potential to increase greenhouse profitability

Posted: 25 Feb 2014 09:24 AM PST

Using data from experiments on gardenia production, researchers determined and applied benefits/costs formulas for assessing profitability of sensor-based irrigation systems. Results showed that sensor-controlled irrigation cut production time and crop losses by more than half. The researchers concluded that controlling irrigation using wireless sensor systems is likely to substantially increase profitability in greenhouse and nursery growing operations.

Reciprocity and parrots: Griffin the grey parrot appears to understand benefits of sharing, study suggests

Posted: 25 Feb 2014 09:23 AM PST

A study into whether grey parrots understand the notion of sharing suggests that they can learn the benefits of reciprocity. The research involved a grey parrot called Griffin, who consistently favoured the option of 'sharing' with two different human partners.

Magnetic Medicine: Nanoparticles target cancer-fighting immune cells

Posted: 25 Feb 2014 09:22 AM PST

Using tiny particles designed to target cancer-fighting immune cells, researchers have trained the immune systems of mice to fight melanoma, a deadly skin cancer. The experiments represent a significant step toward using nanoparticles and magnetism to treat a variety of conditions, the researchers say. They also note that in addition to its potential medical applications, combining nanoparticles and magnetism may give researchers a new window into fundamental biological processes.

'Greener' aerogel technology holds potential for oil and chemical clean-up

Posted: 25 Feb 2014 08:29 AM PST

A group of researchers is examining alternative materials that can be modified to absorb oil and chemicals without absorbing water. If further developed, the technology may offer a cheaper and 'greener' method to absorb oil and heavy metals from water and other surfaces.

Two biodegradable mulches found to be suitable polyethylene alternatives

Posted: 25 Feb 2014 08:29 AM PST

Three potentially biodegradable plastic mulch products were evaluated by scientists over two growing seasons of broccoli to determine deterioration before and after soil incorporation. Pretillage mulch deterioration was evaluated in both growing seasons by rating the percent of visual deterioration. Post-incorporation mulch deterioration was measured for 13 months at the end of the first growing season. Results showed that two of the mulches could be suitable alternatives to polyethylene mulch for broccoli production in the Pacific Northwest.

Tiger lily heights controlled with flurprimidol preplant bulb soaks

Posted: 25 Feb 2014 08:29 AM PST

The appropriate concentration of flurprimidol for the 'orange tiger' tiger lily has been evaluated by scientists, who tested for residual effects of flurprimidol the following year. These researchers found that flurprimidol used at optimal concentrations does not affect plant growth or flowering during the second season. The team also found differential responses to flurprimidol for three other tiger lily cultivars, and recommended that growers conduct preplant bulb soak trials to determine optimal concentrations before applying flurprimidol to an entire crop.

Hurricane prediction: Real time forecast of Hurricane Sandy had track and intensity accuracy

Posted: 25 Feb 2014 07:16 AM PST

A real-time hurricane analysis and prediction system that effectively incorporates airborne Doppler radar information may accurately track the path, intensity and wind force in a hurricane, according to meteorologists. This system can also identify the sources of forecast uncertainty.

MERS virus widespread in Saudi Arabian camels: Coronavirus has been infecting the animals for at least 20 years

Posted: 25 Feb 2014 07:15 AM PST

The coronavirus responsible for Middle East Respiratory Syndrome (MERS) is prevalent in camels throughout Saudi Arabia and has been around for at least 20 years, according to a new study.

Strawberries lower cholesterol, study suggests

Posted: 25 Feb 2014 07:12 AM PST

A team of volunteers ate half a kilo of strawberries a day for a month to see whether it altered their blood parameters in any way. At the end of this unusual treatment, their levels of bad cholesterol and triglycerides were significantly reduced, according to the analyses conducted by Italian and Spanish scientists. Several studies had already demonstrated the antioxidant capacity of strawberries, but now researchers conducted an analysis that revealed that these fruits also help to reduce cholesterol.

Ceausescu's flying bears: Molecular genetics provides evidence for an unusual dispersal mode in European brown bears

Posted: 25 Feb 2014 07:11 AM PST

Scientists use genetics to confirm the legend of bears flown in for the hunting pleasures of other countries' rulers. A genetic study of brown bears in Bulgarian mountain regions provided evidence for the existence of individuals of Carpathian origin. How did they get there? Natural dispersal is unlikely. Rather, the bears were brought in by air transport.

The importance of (experimental) design

Posted: 25 Feb 2014 07:11 AM PST

One of the hottest debates in evolutionary biology concerns the origin of behavior: is it genetically encoded or do animals and birds copy their parents or other individuals? A classic experiment published in 2000 seemed to provide overwhelming evidence that a particular behavioral choice (whether individuals of a species of swallow breed in a small colony or a large one) is largely genetically determined. Scientists have now re-examined the data and shown that the findings could be explained by random choice.

Cyclones and frost: Two climate change myths debunked

Posted: 25 Feb 2014 07:11 AM PST

Scientists have debunked two big myths around climate change by proving firstly, that despite predictions, tropical storms are not increasing in number. However, they are shifting, and South Africa could be at increased risk of being directly impacted by tropical cyclones within the next 40 years. Secondly, while global warming is causing frost to be less severe, late season frost is not receding as quickly as flowering is advancing, resulting in increased frost risk which will likely begin to threaten food security.

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