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Dolphins Have "Names," Respond When Called

Dolphins Have "Names," Respond When Called | Amazing Science | Scoop.it
Dolphins respond to recordings of their own whistles—suggesting they use names to communicate in the wild, a new study says.


We already knew that bottlenose dolphins can follow "recipes" in preparing mollusks, help other species in distress, and possibly do math. So it may come as no surprise that the marine mammals also call each other by whistles that act as names.


Past studies have shown that individual dolphins have a unique whistle, called a "signature whistle," that they often use in big group settings, like when several pods of dolphins meet at sea.


The idea that dolphins have a name in the form of a whistle has been around since the 1960s, and studies of captive dolphins have shown that the animals are responsive to the whistles of dolphins they know.


But a new study takes the theory a step further by asserting that a dolphin will respond when it hears the sound of its own signature whistle, repeating that whistle back in a way that seems to say, "Yup, I'm here—did you call my name?" explained Whitney Friedman, a dolphin-behavior expert at the University of California, San Diego.


It's "compelling evidence" that the dolphin indeed uses the sound as a name, according to the study, published July 22 in the Proceedings of the National Academy of Sciences.


The research was performed by a group of scientists on a boat off eastern Scotland who joined up with a group of wild dolphins. When one of the dolphins announced itself with its signature whistle—the equivalent of "Joey!" for instance—the researchers recorded that sound.


Later, the team played that same "Joey!" call back to the dolphins, and a significant portion of the time, the dolphin they called Joey responded with the same call—as if Joey was saying, "Yup, I'm here."


The dolphins responded a little when the scientists played recordings of whistles of familiar dolphins from the same population, but did not respond at all to unfamiliar dolphins from a different population. (Watch video: "Dolphin Talk Decoded.")

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BBC: Timeline of the far future — What we can expect in a billion and more years...

BBC: Timeline of the far future — What we can expect in a billion and more years... | Amazing Science | Scoop.it
What do we expect will happen in one thousand years time? Or one million years? Or even one billion? As our amazing timeline shows, there may be trouble ahead.


The Earth's oceans will disappear in about one billion years due to increased temperatures from a maturing sun. However,  the Earth's problems may begin in half that time because of falling levels of carbon dioxide in the atmosphere, according to a Penn State researcher.


"The sun, like all main sequence stars, is getting brighter with time and that affects the Earth's climate," says Dr. James F. Kasting, professor of meteorology and geosciences. "Eventually temperatures will become high enough so that the oceans evaporate." At 140 degrees Fahrenheit, water becomes a major constituent of the atmosphere. Much of this water migrates to the stratosphere where it is lost to the vacuum. Eventually, the oceans will evaporate into space.


"Astronomers always knew that the oceans would evaporate, but they typically thought it would occur only when the sun left the main sequence," Kasting told attendees today (Feb. 20) at the annual meeting of the American Association for the Advancement of Science. "That will be in 5 billion years."


Stars leave the main sequence when they stop burning hydrogen. The sun, a yellow, G-2 star, will then become a red giant encompassing the orbit of Mercury. Mercury will disappear and Venus will lose its atmosphere and become a burnt out planet. The Earth will suffer the same fate, even though it is outside the red giant’s immediate reach. "However, the oceans may evaporate much earlier," says Kasting, a faculty member with the College of Earth and Mineral Sciences. "My calculations are somewhat pessimistic and present a worst case scenario that does not include the effects of clouds, but they say a billion years."


This model was developed with Ken Caldeira, now at Lawrence Livermore Laboratory. Things may go bad long before the Earth is a waterless desert. As the climate becomes warmer, the cycle of silicate rock weathering speeds up. This cycle removes carbon dioxide from the atmosphere and sequesters it in the oceans as calcium carbonate.


"The silicate weathering cycle stabilizes the Earth’s climate for a time," says Kasting. "Eventually, atmospheric carbon dioxide levels will become so low that it will not be able to do so, but before then, there will not be sufficient carbon dioxide to sustain most plants."


Plants use carbon dioxide in photosynthesis to convert the sun's energy to sugars and other carbohydrates. Two main kinds of photosynthesis exist, C3 and C4. In a half billion years, the models predict that carbon dioxide will be at the compensation point for C3 plants which make up 95 percent of all plants. Below the compensation point, carbon dioxide is not concentrated enough for these plants to photosynthesize. C3 plants include trees and most crops.


C4 plants, which include corn, sugar cane and other tropical grasses, can still photosynthesize because they have an internal mechanism to concentrate carbon dioxide, but these plants cannot sustain the biosphere as we know it today.


"If carbon dioxide levels in the atmosphere continue to increase over the next few centuries, they could remain high for a very long time," says Kasting. "Then, after fossil fuels run out, it would take a million years or so for levels to return to present."


But even if there is a pulse of high carbon dioxide in the near future, by a half billion years, levels will be too low for productive plant life. "Obviously, a billion, even a half billion years, are a long way off in the future," says Kasting. "However, these models can help us refine our understanding of the time that a planet remains in an orbit where life can exist."


Only a narrow spherical shell of space exists at a distance from a star that is neither too cold nor too warm for life. As a sun matures and brightens, that spherical shell moves outward. A planet must remain in the livable shell for long enough for life to evolve, even while that band moves outward. If planets lose their water supply, a mandatory requirement for life, earlier than previously thought, then that creates a shorter window for livable planets.


"If we calculated correctly, Earth has been habitable for 4.5 billion years and only has a half billion years left," says Kasting.

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odysseas spyroglou's curator insight, January 13, 2014 2:44 AM

Is it any easier today with all the tools that we have at hand to predict future ?

Anne Fleischman's curator insight, January 13, 2014 10:12 AM

Un exercice de prospective à très très très long terme. Dommage on ne sera plus là pour vérifier...

Jose Mejia R's curator insight, January 13, 2014 1:13 PM

 I find it interesting that these assumptions , almost certainly based on scientific speculations indicate that if it is not consumed by a swollen sun after 5.4 billion years , the Earth's orbit would eventually collapse and plunge into the sun.

The doctrine of evolutionary creation states that in a solar system like ours , a myriad of primeval virgin spirits originates or emanates ' from the Central Sun, " discriminates evolutionarily in such generating means and then is ejected to different orbits at different periods time to adjust itself in vibrant radiant globes. Finally, in different cosmic periods each balloon will evolve into a more complex steps and become a planet as it is now known to and through a process of evolutionary creation, first regress to sink into the matterl in successive continuing times and then slowly evolve from matter as omnipotent and omniscient individual spiritual self-aware entities, thus returning to " the mansions of the Father ," whose visible symbol is the Sun, with respect to our planetary system. JMR


 

Me parece interesante que estas suposiciones, casi con toda seguridad basadas en especulaciones científicas, indican que si no es consumida por un Sol hinchado luego de 5,4 mil millones de años, la órbita de la Tierra finalmente colapsaría y sería zambullida en el sol.

 

 

 

La doctrina de la creación evolutiva afirma que en un sistema solar como el nuestro, una miríada de espíritus virginales primigenia proviene o es emanada ' en el Sol Central ', se discrimina evolutivamente en tales medios generatrices y luego es expulsada a órbitas diferentes en diferentes períodos de tiempo para ajustarse a sí misma en vibrante globos radiantes. Finalmente, en diferentes períodos cósmicos cada globo va a evolucionar a otro etapas más complejas y se convertirá en un planeta como es conocido ahora con el fin de y por medio de un proceso de creación evolutiva, primeramente involucionar al sumirse en la materia en sucesivas y continuas épocas y luego evolucionar lentamente desde la materia como omnipotentes y omniscientes entidades individuales espirituales, conscientes de sí mismas, volviendo así a " las mansiones del Padre", cuyo símbolo visible es nuestro Sol , en lo que respecta a nuestro sistema planetario . JMR .


 

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Magnetic metamaterial superlens extends range of wireless power transfer

Magnetic metamaterial superlens extends range of wireless power transfer | Amazing Science | Scoop.it

Inventor Nikola Tesla imagined the technology to transmit energy through thin air almost a century ago, but experimental attempts at the feat have so far resulted in cumbersome devices that only work over very small distances. But now, Duke University researchers have demonstrated the feasibility of wireless power transfer using low-frequency magnetic fields over distances much larger than the size of the transmitter and receiver.

The advance comes from a team of researchers in Duke's Pratt School of Engineering, who used metamaterials to create a "superlens" that focuses magnetic fields. The superlens translates the magnetic field emanating from one power coil onto its twin nearly a foot away, inducing an electric current in the receiving coil.


The experiment was the first time such a scheme has successfully sent power through the air with an efficiency many times greater than what could be achieved with the same setup minus the superlens. "For the first time we have demonstrated that the efficiency of magneto-inductive wireless power transfer can be enhanced over distances many times larger than the size of the receiver and transmitter," said Yaroslav Urzhumov, assistant research professor of electrical and computer engineering at Duke University. "This is important because if this technology is to become a part of everyday life, it must conform to the dimensions of today's pocket-sized mobile electronics."


In the experiment, Yaroslav and the joint Duke-Toyota team created a square superlens, which looks like a few dozen giant Rubik's cubes stacked together. Both the exterior and interior walls of the hollow blocks are intricately etched with a spiraling copper wire reminiscent of a microchip. The geometry of the coils and their repetitive nature form a metamaterial that interacts with magnetic fields in such a way that the fields are transmitted and confined into a narrow cone in which the power intensity is much higher.

"If your electromagnet is one inch in diameter, you get almost no power just three inches away," said Urzhumov. "You only get about 0.1 percent of what's inside the coil." But with the superlens in place, he explained, the magnetic field is focused nearly a foot away with enough strength to induce noticeable electric current in an identically sized receiver coil.


Urzhumov noted that metamaterial-enhanced wireless power demonstrations have been made before at a research laboratory of Mitsubishi Electric, but with one important caveat: the distance the power was transmitted was roughly the same as the diameter of the power coils. In such a setup, the coils would have to be quite large to work over any appreciable distance.

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Protein Found Responsible For Some Genetic Deafness

Protein Found Responsible For Some Genetic Deafness | Amazing Science | Scoop.it

Some people lose their hearing because they simply age; some because of too much loud noise. For some, the ability to hear never developed.

Researchers at the Scripps Research Institute in La Jolla, Calif., have discovered a protein that is responsible for one form of genetic deafness. The protein helps turn sound into electrical signals.


The research is of more than just biochemical interest; it may also open a new avenue for possibly giving the sense of hearing to some of those who are born without it. The team, led by Ulrich Mueller, a professor of cell biology, took newborn deaf mice and inserted the protein, called TMHS, into their sensory cells for sound perception, giving the mice some form of hearing. The potential now exists for genetic therapy to insert the genes for the protein into newborn humans and fix malfunctioning cells. The work is published in the Dec. 7, 2013 issue of the journal "Cell".


No one knows how many people suffer from genetic deafness but they surely number in the millions, Mueller said. According to the Centers for Disease Control and Prevention, genetic causes are responsible for half the children born deaf in the U.S. Sixty genes have been identified so far, and there likely are many more to be found. Mueller said that the best guess now is that there are 400-500 genes and proteins responsible for genetic deafness.


Sound is channeled by our outer ear into the ear canal where it strikes the ear drum in the middle ear. The eardrum vibrates, and those vibrations move utilizing a set of delicate bones deeper inside the ear to the cochlea, a spiral structure filled with fluid. The vibration in the bones shakes the fluid in the cochlea. A complex of hair-like cells in the cochlea senses the vibrations in the fluid. "The hair cells have stereocilia, little filaments, projections that stick out from the hair cells," Mueller said. The stereocilia sense the motion. It is at that point, the TMHS protein gets involved. TMHS triggers electrical signals in nerve cells surrounding the hair cells. The signals then travel to the brain and are sensed as sound, Mueller said.


The TMHS protein opens holes in the hair cells called ion channels. "Anything that goes into a cell is controlled by proteins," Mueller said.  "The language of the brain is electricity. If you want to send an electric signal, you open the pores in the membrane and let the ion into the cell and that change leads to an electric current."


TMHS is a component of the hair cell’s mechano-transduction machinery and binds to the tip-link component PCDH15 and regulates the tip-link assembly. TMHS regulates transducer channel conductance and is required for adaptation. TMHS is structurally similar to other ion channel regulatory subunits such as TARPs (transmembrane alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor regulatory proteins).

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Conductive ink for drawing circuits for flexible electronic books, displays and wearables

Conductive ink for drawing circuits for flexible electronic books, displays and wearables | Amazing Science | Scoop.it

A picture drawn with conductive ink lights up a green LED (credit: American Chemical Society) Chinese researchers have developed a novel conductive metal.


Chinese researchers have developed a novel conductive metal ink made of  copper nanosheets that can be used in a pen to draw a functioning, flexible electric circuit on regular printer paper. This development could be a step beyond the inkjet-printed circuits. The new process could pave the way for a wide range of new bendable gadgets, such as electronic books that look and feel more like traditional paperbacks, roll-up tablets, and wearables, according to the researchers.


They made copper nanosheets in the laboratory, coated with silver nanoparticles to help the copper nanosheets overlap and stack together in a laminar (multi-layer) structure to improve conductivity. They then incorporated this material into an ink pen, using it to draw patterns of lines, words and even flowers on regular printer paper.


To show that the ink could conduct electricity, the scientists added small LED chips (lights) to the drawing that lit up when the circuit was connected to a battery. To test the ink’s flexibility, they folded the papers 1,000 times, even crumpling them up, and showed that the ink maintained 80 to 90 percent of its conductivity.


Wenjun Dong, Ge Wang and colleagues note that current efforts to create flexible circuits are “complicated, time-consuming, and expensive processes.” The research was funded by the National Natural Science Foundation of China, the Zhejiang Provincial Natural Science Foundation of China, the National High-Tech R&D Program of China, the Program for New Century Excellent Talents in University, and the Program for Changjiang Scholars and Innovative Research Team in University.


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Artefacts from 11,000-Year-Old Seafaring Indians Discovered on California Island

Artefacts from 11,000-Year-Old Seafaring Indians Discovered on California Island | Amazing Science | Scoop.it

Just offshore from the chock-a-block development of Southern California, archaeologists have discovered some of the oldest sites of human occupation on the Pacific Coast.


On Santa Rosa Island, one of the Channel Islands just 65 kilometers from Santa Barbara, nearly 20 sites have been found that reveal signs of prehistoric human activity, from massive middens of abalone shells to distinctive stone points and tool-making debris.


At least nine of the sites have what archaeologists say is “definitive evidence” of ancient Paleoindian occupation, about half of them having been dated to 11,000 to 12,000 years ago — making their inhabitants some of the earliest known settlers of North America’s West Coast.


“Finding these sites and the definitive evidence for early occupation is crucial and tells us that people were there, occupying the landscape at the end of the Pleistocene,” said Dr. Torben Rick of the Smithsonian Institution, who led the survey that uncovered the sites.

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Creating improved inkjet-printable materials for electronics and photonics

Creating improved inkjet-printable materials for electronics and photonics | Amazing Science | Scoop.it

Transition-metal dichalcogenides like molybdenum disulphide have attracted great interest as two-dimensional materials beyond graphene due to their unique electronic and optical properties. Solution-phase processes can be a viable method for producing printable single-layer chalcogenides. Molybdenum disulphide can be exfoliated into monolayer flakes using organolithium reduction chemistry; unfortunately, the method is hampered by low yield, submicron flake size and long lithiation time.


National University of Singapore (NUS) scientists have developed a new method for creating a chemical solution of molybdenum disulfide for use in printable optoelectronic devices such as thin film solar cells, flexible logic circuits, photodetectors, and sensors.


Molybdenum disulfide, combined with gold atoms, is being studied for development of ultrafast, ultrathin logic devices, as noted previously on KurzweilAI.


The process:

  1. Chemically exfoliate (peel off) molybdenum disulfide crystals into high-quality single-layer flakes (the new method achieves higher yield and larger flake size than current methods).
  2. Convert the flakes into an inkjet-printable solution (the good dispersion and high viscosity of the flakes make them highly suitable for inkjet printing).
  3. Print wafer-size films. Current processes of producing printable single-layer chalcogenides (such as molybdenum disulfide) take a long time and the yield is poor. The flakes produced are of submicron sizes, which make it challenging to isolate a single sheet for making electronic devices.


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Environment 360: Faced With Sea Ice Loss, Emperor Penguins Alter Their Breeding Tactics

Environment 360: Faced With Sea Ice Loss, Emperor Penguins Alter Their Breeding Tactics | Amazing Science | Scoop.it

Confronted with the loss of sea ice in some parts of Antarctica, four colonies of emperor penguins have come up with an innovative breeding strategy to adapt to their changing environment. Using satellite images, an international team of scientists tracked the four colonies from 2008 to 2012. In the first three years, the emperor penguins hatched and incubated eggs in their customary fashion — atop the sea ice that freezes during the Antarctic winter and spring. But in 2011 and 2012, sea ice did not form until a month after the breeding season began. As a result, the emperor penguins — the largest penguin species on earth — did something never before witnessed by scientists: They climbed up the nearly sheer walls of large, floating ice shelves — huge structures, often hundreds of square miles in extent, that flow from land-based glaciers into the sea. In the region of the four colonies, the ice shelf walls reach as high as 100 feet, researchers say. The scientists say the altered breeding behavior could demonstrate how ice-dependent emperor penguins may adapt to life in a warming world.

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Brainlike Computers Are Learning From Experience

Brainlike Computers Are Learning From Experience | Amazing Science | Scoop.it

Computers have entered the age when they are able to learn from their own mistakes, a development that is about to turn the digital world on its head.


The first commercial version of the new kind of computer chip is scheduled to be released in 2014. Not only can it automate tasks that now require painstaking programming — for example, moving a robot’s arm smoothly and efficiently — but it can also sidestep and even tolerate errors, potentially making the term “computer crash” obsolete.


The new computing approach, already in use by some large technology companies, is based on the biological nervous system, specifically on how neurons react to stimuli and connect with other neurons to interpret information. It allows computers to absorb new information while carrying out a task, and adjust what they do based on the changing signals.


In coming years, the approach will make possible a new generation of artificial intelligence systems that will perform some functions that humans do with ease: see, speak, listen, navigate, manipulate and control. That can hold enormous consequences for tasks like facial and speech recognition, navigation and planning, which are still in elementary stages and rely heavily on human programming.


Designers say the computing style can clear the way for robots that can safely walk and drive in the physical world, though a thinking or conscious computer, a staple of science fiction, is still far off on the digital horizon.


“We’re moving from engineering computing systems to something that has many of the characteristics of biological computing,” said Larry Smarr, an astrophysicist who directs the California Institute for Telecommunications and Information Technology, one of many research centers devoted to developing these new kinds of computer circuits.


Until now, the design of computers was dictated by ideas originated by the mathematician John von Neumann about 65 years ago. Microprocessors perform operations at lightning speed, following instructions programmed using long strings of 1s and 0s. They generally store that information separately in what is known, colloquially, as memory, either in the processor itself, in adjacent storage chips or in higher capacity magnetic disk drives.


The data — for instance, temperatures for a climate model or letters for word processing — are shuttled in and out of the processor’s short-term memory while the computer carries out the programmed action. The result is then moved to its main memory.


The new processors consist of electronic components that can be connected by wires that mimic biological synapses. Because they are based on large groups of neuron-like elements, they are known as neuromorphic processors, a term credited to the California Institute of Technology physicist Carver Mead, who pioneered the concept in the late 1980s.


They are not “programmed.” Rather the connections between the circuits are “weighted” according to correlations in data that the processor has already “learned.” Those weights are then altered as data flows in to the chip, causing them to change their values and to “spike.” That generates a signal that travels to other components and, in reaction, changes the neural network, in essence programming the next actions much the same way that information alters human thoughts and actions.


“Instead of bringing data to computation as we do today, we can now bring computation to data,” said Dharmendra Modha, an I.B.M. computer scientist who leads the company’s cognitive computing research effort. “Sensors become the computer, and it opens up a new way to use computer chips that can be everywhere.”


Via Szabolcs Kósa
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VendorFit's curator insight, December 31, 2013 3:27 PM

Artificial intelligence is the holy grail of technological achievment, creating an entity that can learn from its own mistakes and can (independently of programmer intervention) develop new routines and programs.  The New York Times claims that the first ever "learning" computer chip is to be released in 2014, an innovation that has profound consequences for the tech market.  When these devices become cheaper, this should allow for robotics and device manufacture that incorporates more detailed sensory input and can parse real objects, like faces, from background noise. 

Laura E. Mirian, PhD's curator insight, January 10, 2014 1:16 PM

The Singularity is not far away

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Distances between galaxies in the universe measured to an accuracy of 1%

Distances between galaxies in the universe measured to an accuracy of 1% | Amazing Science | Scoop.it

Astronomers have measured the distances between galaxies in the universe to an accuracy of just about 1%. This staggeringly precise survey - across six billion light-years - is key to mapping the cosmos and determining the nature of dark energy. The new gold standard was set by BOSS (the Baryon Oscillation Spectroscopic Survey) using the Sloan Foundation Telescope in New Mexico, US. It was announced at the 223rd American Astronomical Society in Washington DC.


"I now know the size of the universe better than the size of my house,”

said Prof. David Schlegel, BOSS principal investigator. "There are not many things in our daily lives that we know to 1% accuracy," said Prof David Schlegel, a physicist at Lawrence Berkeley National Laboratory and the principal investigator of BOSS. 

Twenty years ago astronomers were arguing about estimates that differed by up to 50%. Five years ago, we'd refined that uncertainty to 5%; a year ago it was 2%.

One percent accuracy will be the standard for a long time to come. The BOSS team used baryon acoustic oscillations (BAOs) as a "standard ruler" to measure intergalactic distances.  BAOs are the "frozen" imprints of pressure waves that moved through the early universe - and help set the distribution of galaxies we see today. "Nature has given us a beautiful ruler," said Ashley Ross, an astronomer from the University of Portsmouth.

"The ruler happens to be half a billion light years long, so we can use it to measure distances precisely, even from very far away." Determining distance is a fundamental challenge of astronomy: "Once you know how far away it is, learning everything else about it is suddenly much easier," said Daniel Eisenstein, director of the Sloan Digital Sky Survey III.


The BOSS distances will help calibrate fundamental cosmological properties - such as how "dark energy" accelerates the expansion of the universe.  An analysis of the current data - 90% complete - is published on the Arxiv preprint server, with final results expected in June.


After that, future surveys will have to start filling in the enormous gaps between the vast boundaries the BOSS team have defined - and to go much deeper in space. This latter task will be a key objective of Europe's Euclid space telescope due to launch at the end of the decade.

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Great white sharks live much longer than previously thought — for over 70 years

Great white sharks live much longer than previously thought — for over 70 years | Amazing Science | Scoop.it

Using a new technique to age the tissues of these impressive creatures, scientists have identified a male great white that lived into its 70s. The researchers say the finding has important implications for the animals' protection.


Knowing the longevity of a species, how fast it grows and when it reaches sexual maturity is vital information for designing conservation programmes. "These creatures are amazing and it's fascinating to study them," said Li Ling Hamady, who is part of a joint programme between MIT and the Woods Hole Oceanographic Institution in the US.


"Everyone thinks they know these animals so well, and the public perception is that they're either loved or hated. But in terms of the science, we're only just now beginning to understand what they eat, where they go and how long they live."


Scientists have tried to age the spectacular predators by counting annual growth rings in their tissues, such as in their vertebrae. But the sharks' cartilage skeleton makes the division between these rings hard to discern even under the microscope. Now, Ms Hamady and colleagues tell the journal Plos One that they made these rings easier to read by looking for a known radioactive marker.

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Massive Exoplanets Likely To Have Both, Oceans And Continents

Massive Exoplanets Likely To Have Both, Oceans And Continents | Amazing Science | Scoop.it

Water Cycling Between Ocean and Mantle: Super-Earths Need Not Be Waterworlds. Massive terrestrial planets, called “super-Earths,” are known to be common in our galaxy, the Milky Way. Now a Northwestern University astrophysicist and a University of Chicago geophysicist report the odds of these planets having an Earth-like climate are much greater than previously thought.


Nicolas B. Cowan and Dorian Abbot’s new model challenges the conventional wisdom which says super-Earths actually would be very unlike Earth -- each would be a waterworld, with its surface completely covered in water. They conclude that most tectonically active super-Earths -- regardless of mass -- store most of their water in the mantle and will have both oceans and exposed continents, enabling a stable climate such as Earth’s.


Cowan is a postdoctoral fellow at Northwestern’s Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA), and Abbot is an assistant professor in geophysical sciences at UChicago.

“Are the surfaces of super-Earths totally dry or covered in water?” Cowan said. “We tackled this question by applying known geophysics to astronomy.


“Super-Earths are expected to have deep oceans that will overflow their basins and inundate the entire surface, but we show this logic to be flawed,” he said. “Terrestrial planets have significant amounts of water in their interior. Super-Earths are likely to have shallow oceans to go along with their shallow ocean basins.”


In their model, Cowan and Abbot treated the intriguing exoplanets like Earth, which has quite a bit of water in its mantle, the rocky part that makes up most of the volume and mass of the planet. The rock of the mantle contains tiny amounts of water, which quickly adds up because the mantle is so large. And a deep water cycle moves water between oceans and the mantle.


Cowan presented the findings at a press conference, “Windows on Other Worlds,” held Jan. 7 at the 223rd meeting of the American Astronomical Society (AAS) annual meeting in Washington, D.C. He also will discuss the research at a scientific session to be held from 2 to 3:30 p.m. EST Wednesday, Jan. 8, at the AAS meeting (Potomac Ballroom D, Gaylord National Resort and Convention Center). The study will be published Jan. 20 in The Astrophysical Journal.

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Bird-eating fish catches swallows during flight

Bird-eating fish catches swallows during flight | Amazing Science | Scoop.it
Tigerfish swallows swallows after grabbing them out of the air over African lake.


The waters of the African lake seem calm and peaceful. A few migrant swallows flit near the surface. Suddenly, leaping from the water, a fish grabs one of the famously speedy birds straight out of the air. “The whole action of jumping and catching the swallow in flight happens so incredibly quickly that after we first saw it, it took all of us a while to really fully comprehend what we had just seen,” says Nico Smit, director of the Unit for Environmental Sciences and Management at North-West University in Potchefstroom, South Africa.


This is the first confirmed record of a freshwater fish preying on birds in flight, the team reports in the Journal of Fish Biology1. Rumours of such behaviour by the African tigerfish (Hydrocynus vittatus), which has been reported as reaching one metre in length, have circulated since the 1940s. But Smit says that his team was “never really convinced by the anecdotal reports”. So, when they set out to study of the migration and habitat use of these animals in a South African lake in the Mapungubwe National Park, near the border with Botswana and Zimbabwe, they were not necessarily looking for fish flying out of the water.

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Pine Island glacier's retreat is now irreversible

Pine Island glacier's retreat is now irreversible | Amazing Science | Scoop.it
Pine Island Glacier, the largest single contributor to sea-level rise in Antarctica, has started shrinking, say scientists.


Nature Climate Change, shows the glacier's retreat may have begun an irreversible process that could see the amount of water it is adding to the ocean increase five-fold. 'At the Pine Island Glacier we have seen that not only is more ice flowing from the glacier into the ocean, but it's also flowing faster across the grounding line - the boundary between the grounded ice and the floating ice. We also can see this boundary is migrating further inland,' says Dr G. Hilmar Gudmundsson from NERC's British Antarctic Survey, a researcher on the project.

The team, which included scientists from the CSC-IT Center for Science in Finland, the Chinese Academy of Sciences and the Universities of Exeter and Bristol, used three computer models as well as field observations to study how the glacier's ice flows and to simulate how this will change over the coming decades. All the models agreed that the Pine Island Glacier has become unstable, and will continue to retreat for tens of kilometres.

'The Pine Island Glacier shows the biggest changes in this area at the moment, but if it is unstable it may have implications for the entire West Antarctic Ice Sheet,' says Gudmundsson. 'Currently we see around two millimetres of sea level rise a year, and the Pine Island Glacier retreat could contribute an additional 3.5 - 5 millimeters in the next twenty years, so it would lead to a considerable increase from this area alone. But the potential is much larger.'
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Gravitational Lens Magnifies First Discovered SNIa

Gravitational Lens Magnifies First Discovered SNIa | Amazing Science | Scoop.it

Researchers at the Kavli IPMU, led by Robert Quimby, have discovered the first ever Type Ia supernova (SNIa), extraordinarily magnified by a gravitational lens. Scientists wrote in the Astrophysics Journal Letters they discovered the supernova, PS1-10afx, with the Panoramic Survey Telescope & Rapid Response System 1 (Pan-STARRS1). The supernova exploded over 9 billion years ago, making it a much further object than most studied by Pan-STARRS1.


The supernova stood out from other Pan-STARRS1 objects because it was very red and its brightness changed as fast as normal supernovae. No known physical model helped the team explain how supernova could simultaneously be so luminous, so red and so fast. They found PS1-10afx fits in line with other SNIa, but its observed brightness is far too high for such a distant supernova, leaving gravitational lensing as the only explanation.


Gravitational lensing helps to magnify a distant object in space. While light travels through space in “straight” lines, massive objects warp space and cause rays of light to “bend” around them, helping to magnify that brightness and enabling scientists to observe very distant objects. Thus, if there were a sufficiently massive object aligned between us and PS1-10afx, the supernova would appear brighter.


The object helping to provide the gravitational lensing effect may be detectable after the supernova has faded away, so future observations may be able to provide final confirmation of this scenario. The team’s observations are the first showing a strongly lensed Type Ia supernova. A few years ago, Masamune Oguri, one of the co-authors of the team, predicted Pan-STARRS1 would be capable of discovering strongly lensed SNIa. Now that the team has proven this to be true, next generation surveys with the Hyper Suprime-Cam on the Subaru Telescope and other telescopes can be tuned to discover even more strongly lensed SNIa.


Scientists have used gravitational lensing to help uncover many details about the history of the Universe. In March, scientists making observations with the Atacama Large Millimeter/submillimeter Array (ALMA) telescope say they were able to use this method to see the universe making new stars at its very early stages. Two of the galaxies observed by this group of scientists are the most distant ever seen, one of which started emitting light when the Universe was just a billion years old.

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Scientists have found that memories may be passed down through generations in our DNA

Scientists have found that memories may be passed down through generations in our DNA | Amazing Science | Scoop.it

New research from Emory University School of Medicine, in Atlanta, has shown that it is possible for some information to be inherited biologically through chemical changes that occur in DNA. During the tests they learned that that mice can pass on learned information about traumatic or stressful experiences – in this case a fear of the smell of cherry blossom – to subsequent generations.


Using olfactory molecular specificity, the researchers examined the inheritance of parental traumatic exposure, a phenomenon that has been frequently observed, but is not fully understood. The scientists subjected F0 mice to odor fear conditioning before conception and found that subsequently conceived F1 and F2 generations had an increased behavioral sensitivity to the F0-conditioned odor, but not to other odors. When an odor (acetophenone) that activates a known odorant receptor (Olfr151) was used to condition F0 mice, the behavioral sensitivity of the F1 and F2 generations to acetophenone was complemented by an enhanced neuroanatomical representation of the Olfr151 pathway.


Bisulfite sequencing of sperm DNA from conditioned F0 males and F1 naive offspring revealed CpG hypomethylation in the Olfr151 gene. In addition, in vitro fertilization, F2 inheritance and cross-fostering revealed that these transgenerational effects are inherited via parental gametes.


These findings provide a framework for addressing how environmental information may be inherited transgenerationally at behavioral, neuroanatomical and epigenetic levels.


Professor Marcus Pembrey, a paediatric geneticist at University College London, said the work provided “compelling evidence” for the biological transmission of memory. He added: “It addresses constitutional fearfulness that is highly relevant to phobias, anxiety and post-traumatic stress disorders, plus the controversial subject of transmission of the ‘memory’ of ancestral experience down the generations.


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Quantum mechanics explains efficiency of photosynthesis

Quantum mechanics explains efficiency of photosynthesis | Amazing Science | Scoop.it

Light-gathering macromolecules in plant cells transfer energy by taking advantage of molecular vibrations whose physical descriptions have no equivalents in classical physics, according to the first unambiguous theoretical evidence of quantum effects in photosynthesis published today in the journal Nature CommunicationsScientists have observed previously the quantum character of light transport through the molecular machines at work in natural photosynthesis.


The majority of light-gathering macromolecules are composed of chromophores (responsible for the colour of molecules) attached to proteins, which carry out the first step of photosynthesis, capturing sunlight and transferring the associated energy highly efficiently. Previous experiments suggest that energy is transferred in a wave-like manner, exploiting quantum phenomena, but crucially, a non-classical explanation could not be conclusively proved as the phenomena identified could equally be described using classical physics.


Often, to observe or exploit quantum mechanical phenomena systems need to be cooled to very low temperatures. This however does not seem to be the case in some biological systems, which display quantum properties even at ambient temperatures.


Now, a team at UCL have attempted to identify features in these biological systems which can only be predicted by quantum physics, and for which no classical analogues exist.


"Energy transfer in light-harvesting macromolecules is assisted by specific vibrational motions of the chromophores," said Alexandra Olaya-Castro (UCL Physics & Astronomy), supervisor and co-author of the research. "We found that the properties of some of the chromophore vibrations that assist energy transfer during photosynthesis can never be described with classical laws, and moreover, this non-classical behaviour enhances the efficiency of the energy transfer."


Molecular vibrations are periodic motions of the atoms in a molecule, like the motion of a mass attached to a spring. When the energy of a collective vibration of two chromphores matches the energy difference between the electronic transitions of these chromophores a resonance occurs and efficient energy exchange between electronic and vibrational degrees of freedom takes place.


Providing that the energy associated to the vibration is higher than the temperature scale, only a discrete unit or quantum of energy is exchanged. Consequently, as energy is transferred from one chromophore to the other, the collective vibration displays properties that have no classical counterpart.


The UCL team found the unambiguous signature of non-classicality is given by a negative joint probability of finding the chromophores with certain relative positions and momenta. In classical physics, probability distributions are always positive.


"The negative values in these probability distributions are a manifestation of a truly quantum feature, that is, the coherent exchange of a single quantum of energy," explained Edward O'Reilly (UCL Physics & Astronomy), first author of the study. "When this happens electronic and vibrational degrees of freedom are jointly and transiently in a superposition of quantum states, a feature that can never be predicted with classical physics."

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Scientists have revived Daphnia waterflees that have been buried at the bottom of a lake for a 700 years

Scientists have revived Daphnia waterflees that have been buried at the bottom of a lake for a 700 years | Amazing Science | Scoop.it

Scientists hve resurrected animals that are known scientifically as Daphnia and informally as water fleas. About as big as a grain of rice, these shrimp-like organisms live by the billions in lakes. Each fall, some species produce hard-shelled eggs which fall to the bottom of lakes, and the next spring many produce new water fleas. But some of these eggs get buried in sediment, unhatched.


In the mid-1990s, Lawrence J. Weider, an evolutionary ecologist then working in Germany, figured out how coax the eggs to hatch. His first success came with eggs buried for decades in a German lake. Some of the revived animals were in such good shape they could reproduce in his lab.


In 2009 Dr. Weider, now at the University of Oklahoma, and his colleagues set out to resurrect eggs from some lakes in Minnesota. The chemistry of those lakes has been carefully documented for decades, making it possible to see how changes in pollution levels affected the water fleas.


To gather the animals, Dr. Weider and his colleagues took a boat out on the lakes. “It’s a smaller version of a party barge, with a hole cut out of the deck,” he said. Through the hole, the scientists lowered a tube and pushed it about three feet into the sediment — deep enough, Dr. Weider thought, to gather water flea eggs a few decades old.


The scientists then went back to Oklahoma, sifted the cases from the mud, and started resurrecting the animals. They also extracted Daphnia DNA, giving them more data to analyze. Only then did Dr. Weider get an estimate for the age of the sediment in South Center Lake from another lab. “I said, ‘Are you kidding me?'” said Dr. Weider. The lab concluded that the bottom of the lake’s sediment core was about 1,600 years old.


The oldest eggs that Dr. Weider and his colleagues had successfully hatched were about 700 years old. To estimate the age of the sediment, the lab measured levels of a radioactive isotope called lead-210. The researchers are now confirming the dates by measuring another isotope, carbon-14. While the dating remains provisional for now, Dr. Post said he was confident that the oldest of the water fleas lived before Europeans colonized the United States.

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Engineers make world’s fastest organic transistor, heralding new generation of see-through electronics

Engineers make world’s fastest organic transistor, heralding new generation of see-through electronics | Amazing Science | Scoop.it
Teams from Stanford and the University of Nebraska-Lincoln collaborate to make thin, transparent semiconductors that could become the foundation for cheap, high-performance displays. 

Research teams led by Zhenan Bao, professor of chemical engineering at Stanford, and Jinsong Huang, assistant professor of mechanical and materials engineering at UNL used their new process to make organic thin-film transistors with electronic characteristics comparable to those found in expensive, curved-screen television displays based on a form of silicon technology. 


They achieved their speed boost by altering the basic process for making thin-film organic transistors. Typically, researchers drop a special solution, containing carbon-rich molecules and a complementary plastic, onto a spinning platter – in this case, one made of glass. The spinning action deposits a thin coating of the materials over the platter.


First they spun the platter faster. Second they only coated a tiny portion of the spinning surface, equivalent to the size of a postage stamp. These innovations had the effect of depositing a denser concentration of the organic molecules into a more regular alignment. The result was a great improvement in carrier mobility, which measures how quickly electrical charges travel through the transistor.


The researchers called this improved method “off-center spin coating.” The process remains experimental, and the engineers cannot yet precisely control the alignment of organic materials in their transistors or achieve uniform carrier mobility.


Even at this stage, off-center spin coating produced transistors with a range of speeds much faster than those of previous organic semiconductors and comparable to the performance of the polysilicon materials used in today’s high-end electronics.


Further improvements to this experimental process could lead to the development of inexpensive, high-performance electronics built on transparent substrates such as glass and, eventually, clear and flexible plastics. Already, the researchers have shown that they can create high-performance organic electronics that are 90 percent transparent to the naked eye.


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Metastatic cancer cells implode on protein contact using E-selecting and TRAIL

Metastatic cancer cells implode on protein contact using E-selecting and TRAIL | Amazing Science | Scoop.it

By attaching a cancer-killer protein to white blood cells, Cornell biomedical engineers have demonstrated the annihilation of metastasizing cancer cells traveling throughout the bloodstream.

The study, “TRAIL-Coated Leukocytes that Kill Cancer Cells in the Circulation,” was published online the week of Jan. 6 in the journal Proceedings of the National Academy of Sciences.


“These circulating cancer cells are doomed,” said Michael King, Cornell professor of biomedical engineering and the study’s senior author. “About 90 percent of cancer deaths are related to metastases, but now we’ve found a way to dispatch an army of killer white blood cells that cause apoptosis – the cancer cell’s own death – obliterating them from the bloodstream. When surrounded by these guys, it becomes nearly impossible for the cancer cell to escape.”


King and his colleagues injected human blood samples, and later mice, with two proteins: E-selectin (an adhesive) and TRAIL (Tumor Necrosis Factor Related Apoptosis-Inducing Ligand). The TRAIL protein joined together with the E-selectin protein stick to leukocytes – white blood cells – ubiquitous in the bloodstream. When a cancer cell comes into contact with TRAIL, which becomes unavoidable in the chaotic blood flow, the cancer cell essentially kills itself.


“The mechanism is surprising and unexpected in that this repurposing of white blood cells in flowing blood is more effective than directly targeting the cancer cells with liposomes or soluble protein,” say the authors.

In the laboratory, King and his colleagues tested this concept’s efficacy. When treating cancer cells with the proteins in saline, they found a 60 percent success rate in killing the cancer cells. In normal laboratory conditions, the saline lacks white blood cells to serve as a carrier for the adhesive and killer proteins. Once the proteins were added to flowing blood, which models forces, mixing and other human-body conditions, however, the success rate in killing the cancer cells jumped to nearly 100 percent.


In addition to King, the paper’s researchers include first author Michael Mitchell, a Cornell doctoral candidate in the field of biomedical engineering; Elizabeth C. Wayne, a Cornell doctoral student in the field of biomedical engineering; Kuldeepsinh Rana, a Cornell Ph.D. ’11; and Chris Schaffer, associate professor in biomedical engineering. The National Cancer Institute (Physical Sciences-Oncology program) of the National Institutes of Health, Bethesda, Md. funded the research through Cornell’s Center for the Microenvironment and Metastasis.


Metastasis is the spread of a cancer cells to other parts of the body. Surgery and radiation are effective at treating primary tumors, but difficulty in detecting metastatic cancer cells has made treatment of the spreading cancer problematic, say the scientists.

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Bluebrain: Attempt to engineer a full brain, one neuron at a time

Henry Markram is attempting to reverse engineer an entire human brain, one neuron at a time. This piece is an introduction to director Noah Hutton's 10-year film-in-the-making that will chronicle the development of The Blue Brain Project, a landmark endeavor in modern neuroscience.

Year 2: vimeo.com/28040230
Year 3: vimeo.com/51685540
Year 4: vimeo.com/52664485


Further info: [1], [2], [3], [4], [5], [6], and [7]


Szabolcs Kósa

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The Genographic Project -- National Geographic

The Genographic Project -- National Geographic | Amazing Science | Scoop.it

The Genographic Project is a multiyear research initiative led by National Geographic Explorer-in-Residence Dr. Spencer Wells. Dr. Wells and a team of renowned international scientists are using cutting-edge genetic and computational technologies to analyze historical patterns in DNA from participants around the world to better understand our human genetic roots.


The three components of the project are:

  • To gather and analyze research data in collaboration with indigenous and traditional peoples around the world
  • To invite the general public to join this real-time scientific project and to learn about their own deep ancestry by purchasing a Genographic Project Participation and DNA Ancestry Kit, Geno 2.0
  • To use a portion of the proceeds from Geno 2.0 kit sales to further research and the Genographic Legacy Fund, which in turn supports community-led indigenous conservation and revitalization projects


The Genographic Project is anonymous, nonmedical, and nonprofit, and all results are placed in the public domain following scientific peer publication.


Introducing Geno 2.0: Building on the science from the first phase of the Genographic Project, we have developed a cutting-edge new test kit, called Geno 2.0, that enables members of the public to participate in the Genographic Project while learning fascinating insights about their own ancestry. The Geno 2.0 test examines a unique collection of nearly 150,000 DNA identifiers, called “markers,” that have been specifically selected to provide unprecedented ancestry-relevant information.


With a simple and painless cheek swab, you submit a sample of your DNA to our lab. We then run a comprehensive analysis to identify thousands of genetic markers on your mitochondrial DNA, which is passed down each generation from mother to child, to reveal your direct maternal deep ancestry. In the case of men, we will also examine markers on the Y chromosome, which is passed down from father to son, to reveal your direct paternal deep ancestry. In addition, for all participants, we analyze a collection of more than 130,000 other ancestry-informative markers from across your entire genome to reveal the regional affiliations of your ancestry, offering insights into your ancestors who are not on a direct maternal or paternal line.

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Mutation disrupting histamine production in the brain is a cause of Tourette syndrome

Mutation disrupting histamine production in the brain is a cause of Tourette syndrome | Amazing Science | Scoop.it

A rare genetic mutation that disrupts production of histamine in the brain is a cause of the tics and other abnormalities of Tourette syndrome, according to new findings by Yale School of Medicine researchers.


The findings, reported Jan. 8, 2014 in the journal Neuron, suggest that existing drugs that target histamine receptors in the brain might be useful in treating the disorder. Tourette syndrome afflicts up to 1% of children, and a smaller percentage of adults.


“These findings give us a new window into what’s going on in the brain in people with Tourette. That’s likely to lead us to new treatments,” said Christopher Pittenger, associate professor in the psychiatry and psychology departments and in the Yale Child Study Center, and senior author of the paper.


Histamine is commonly associated with allergy, but it also plays an important role as a signaling molecule in the brain. Interactions with this brain system explain why some allergy medications cause people to feel sleepy. 


In 2010, Yale researchers showed that a family with nine members suffering from Tourette’s carried a mutation in a gene called HDC that disrupts the production of histamine. The new work demonstrates that this mutation causes the disorder. Mice with the same mutation develop symptoms similar to those found in Tourette’s, the Yale team showed. Also, these mice and the patients that carry the HDC mutation showed abnormalities in signaling by the neurotransmitter dopamine in parts of the brain associated with Tourette’s and related conditions.


Drug companies have developed medications that target brain-specific histamine receptors in an effort to treat schizophrenia and ADHD. While not approved for general use yet, those drugs or others that target histamine receptors should be tested to see whether they can treat symptoms of Tourette syndrome, Pittenger said.

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Searching for the Amazon's hidden civilizations before Columbus' arrival

Searching for the Amazon's hidden civilizations before Columbus' arrival | Amazing Science | Scoop.it

Statistical model predicts signs of agriculture in the rainforest. A new model of the Amazon predicts that terra preta is more likely to be found along rivers in the eastern part of the rainforest. The letters indicate known archaeological sites.


Look around the Amazon rainforest today and it’s hard to imagine it filled with people. But in recent decades, archaeologists have started to find evidence that before Columbus’s arrival, the region was dotted with towns and perhaps even cities. The extent of human settlement in the Amazon remains hotly debated, partly because huge swaths of the 6-million-square-kilometer rainforest remain unstudied by archaeologists. Now, researchers have built a model predicting where signs of pre-Columbian agriculture are most likely to be found, a tool they hope will help guide future archaeological work in the region.


In many ways, archaeology in the Amazon is still in its infancy. Not only is it difficult to mount large-scale excavations in the middle of a tropical rainforest, but until recently, archaeologists assumed there wasn’t much to find. Amazonian soil is notoriously poor quality—all the nutrients are immediately sucked up by the rainforest’s astounding biodiversity—so for many years, scientists believed that the kind of large-scale farming needed to support cities was impossible in the region. Discoveries of gigantic earthworks and ancient roads, however, hint that densely populated and long-lasting population hubs once existed in the Amazon. Their agricultural secret? Pre-Columbian Amazonians enriched the soil themselves, creating what archaeologists call terra preta.


Terra preta—literally “black earth”—is soil that humans have enriched to have two to three times the nutrient content of the surrounding, poor-quality soil, explains Crystal McMichael, a paleoecologist at the Florida Institute of Technology in Melbourne. Although there is no standard definition for terra preta, it tends to be darker than other Amazonian soils and to have charcoal and pre-Columbian pottery shards mixed in. Most of it was created 2500 to 500 years ago. Like the earthworks, terra preta is considered a sign that a particular area was occupied by humans in the pre-Columbian past.


By analyzing location and environmental data from nearly 1000 known terra preta sites and comparing it with information from soil surveys that reported no terra preta, McMichael and her team found patterns in the distribution of the enriched soil. The scientists concluded that terra pretais most likely to be found in central and eastern Amazonia on bluffs overlooking rivers nearing the Atlantic Ocean. It’s less common in western Amazonia, where runoff from the Andes tends to add nutrients to the soil naturally, and in highland areas such as Llanos de Moxos in Bolivia, which is home to many impressive pre-Columbian earthworks. By analyzing the environmental conditions most strongly associated with terra preta, the team was able to build a model predicting where undiscovered terra preta sites are most likely to be found. Overall, they suspect that there is probably about 154,063 km2 of terra preta in the Amazon, composing about 3.2% of the basin’s total area, they report online today in the Proceedings of the Royal Society B.

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Shocking Study Finds Lions are Nearly Extinct in West Africa

Shocking Study Finds Lions are Nearly Extinct in West Africa | Amazing Science | Scoop.it

Physically and emotionally demanding. That’s how Philipp Henschel, Lion Program Survey Coordinator for the big-cat conservation organization Panthera, describes the six years he and other researchers spent combing the wilds of 17 nations looking for the elusive and rarely studied West African lion. The results of their quest were disheartening to say the least. Back in 2005, before the survey began, West African lions were believed to live in 21 different protected areas. But now a paper about the survey, published today in PLoS One, confirms that lions actually exist in just four of those sites. Worse still, the researchers estimate that the total population for West African lions is only about 400 animals, including fewer than 250 mature individuals of breeding age.


West African lions—historically referred to as the subspecies Panthera leo senegalensis, although that taxonomic designation is not currently in use—are smaller than and genetically distinct from their southern and eastern African relatives, which are also in decline and currently number about 35,000 big cats. Recent genetic tests link them more closely to the extinct Barbary lion of northern Africa and the critically endangered Asiatic lion (Panthera leo persica) in India, which also has a population of about 450 animals.


Although shocking, the news of the lions’ near extinction should probably not come as a surprise given the context of the region. The populations of other large mammal species declined an average of 85 percent in West Africa between 1970 and 2005, mostly to feed the voracious demand of the bushmeat trade. The 11 nations of West Africa are among the poorest on earth and include six of the world’s least developed countries. The countries in the region have no money for conservation, and the study found that most of the protected areas that were expected to contain lions had little to no enforcement, security patrols or management. National parks are frequently overrun by tens of thousands of domesticated cattle. Henschel describes many of the so-called protected areas as “paper parks”—conservation sites in name only.


References:

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Nevermore Sithole's curator insight, January 10, 2014 7:37 AM
Lions are Nearly Extinct in West Africa