Image of the surface of Venus taken by the space probe, Venera 13 (Photo: L. Ksanfomaliti-Solar System Research)

A renowned Russian astronomer drew lots of attention after claiming there is life on Venus.

Leonid Ksanfomaliti, of the Russian Academy of Sciences, analyzed photos made by Venera-13, a Soviet-era space probe that explored Venus.

According to Ksanfomaliti, the photos showed objects – which looked like a disk, black flap and scorpion – that appeared to “emerge, fluctuate and disappear.”

This indicated, he said, that these objects had changed locations on the photos and traces on the ground.

But Ksanfomaliti’s claims are refuted by a number of experts including Jonathon Hill, a researcher and mission planner, who processes many of the images taken during NASA’s Mars missions.

Hill told an online journal his examination of higher-resolution versions of the Venera-13 photos determined one of the objects identified by Ksanfomaliti is not a living creature, but rather a mechanical component.

He points out the very same object also appeared in a photograph that was taken by an identical Venusian landing probe, the Venera-14.  One of the other objects was determined to be nothing more than processed noise.

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Oldest dinosaur nest found

Close-up of embryonic skeleton of Massospondylus from clutch of eggs at the nesting site (Photo: D. Scott)

Scientists excavating in South Africa say they’ve discovered the oldest dinosaur nesting site ever found.

It is 190 million years old and belongs to the prosauropod dinosaur Massospondylus.

The researchers say the discovery reveals significant clues about the evolution of complex reproductive behavior in early dinosaurs.

The scientists found clutches of eggs, many with embryos, as well as tiny dinosaur footprints, which they say is the oldest known evidence showing that dinosaur hatchlings remained at their nesting site long enough to at least double in size.

The dinosaur nesting ground is believed to be more than 100 million years older than previously known nesting sites.

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Saliva HIV test shown to be as accurate as standard blood test

OraQuick ADVANCE® Rapid HIV-1/2 Antibody Test (Photo: OraSure Technologies)

A saliva test is as accurate as traditional blood tests when testing for HIV, according to a new study.

Scientists in Canada analyzed data from five worldwide databases and found the saliva HIV test, OraQuick HIV1/2, had the same accuracy as the blood test for high-risk populations.

The researchers found the saliva test is 99 percent accurate for HIV in high risk populations, and about 97 percent in low risk populations.

The oral HIV test has become popular for a number of reasons, including its acceptability and ease of use.  The test is also non-invasive, pain-free, convenient and provides test results within 20 minutes.

“Getting people to show up for HIV testing at public clinics has been difficult because of visibility, stigma, lack of privacy and discrimination,” says study lead author Dr. Nikita Pant Pai. “A confidential testing option such as self-testing could bring an end to the stigmatization associated with HIV testing.”

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Scientists observe scorpions to learn how to protect machine parts

Androctonus australis - Yellow fattail scorpion (Photo: Creative Commons)

Scientists looking for ways to protect a machine’s moving parts from wear and tear looked to the yellow fattail scorpion for inspiration.

This scorpion uses its bionic shield to protect itself from scratches caused by desert sandstorms.

The researchers examined bumps and grooves found on the scorpions’ backs, scanned the arachnids with a 3D laser device, and developed a special computer program simulating the movement of sand-filled air over the scorpions.

The tools allowed researchers to create a computer model that helped them to develop a number of patterned surfaces to test. The team tested these surfaces by conducting erosion tests on them.

They found that a series of small grooves, cut at a 30-degree angle, gave steel surfaces the best protection from erosion, which they say is a key cause of material damage and equipment failure.

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Large amount of fresh water found in Arctic Ocean

Map of the Arctic Ocean (Image: US Geological Survey)

A large dome of fresh water that’s been building up in the Arctic Ocean over the last 15 years has the potential to impact weather patterns.

English researchers say a change in wind direction could cause this water to spill into the north Atlantic, which in turn would cool Europe.

In a study published in Nature Geoscience, researchers report this fresh-water dome may have been created by strong Arctic winds, which sped up a large ocean circulation known as the Beaufort Gyre, causing the surface of the sea to bulge out.

The researchers say a change in wind direction would allow the fresh water to flow into the remainder of the Arctic Ocean, possibly reaching the north Atlantic.

If this happens, the researchers say a crucial ocean current which originates from the Gulf Stream, could be slowed.

That would then cool Europe.  This current usually helps maintain relatively-mild conditions on the continent compared to other parts of the world located at similar latitudes.

Katharine Giles, the lead author of the study says, “Our next step is to look into how changes in the sea ice cover might affect the coupling between the atmosphere and the ocean in more detail to see if we can confirm this idea.”

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The African lungfish displays primitive walking behaviors in controlled conditions. (Photo: Yen-Chyi Liu/University of Chicago)

When you look at an African lungfish, you see an aquatic animal with an eel-like body and what appear to be small, scrawny limbs, which are actually pelvic fins.

A new study suggests this creature could up-end what we thought we knew about the evolution of life on Earth as it made its way from water to land.

After extensive video analysis,  University of Chicago researchers found the African Lungfish uses its pelvic fins to lift itself off the surface and propel itself forward. Before now,  scientists believed these abilities originated in the early species of tetrapods – creatures with four feet who appeared on Earth later than the lungfish’s ancestors.

The researchers think their observations will reshuffle our understanding of the order of evolutionary events that led up to creatures adapting to life on land. Fossil tracks thought to be the work of early tetrapods species could have instead been produced by lobe-finned ancestors of the lungfish.

The study’s lead author,  graduate student Heather King, and her colleagues designed and built a special tank to study and videotape the lungfish from the side and below for in-depth analysis. They chose to videotape and observe the lungfish in action, because if they only looked at the bones, as one would with a fossil, it might not be apparent the animals could have the ability of locomotion.

Researchers found the African Lungfish uses its pelvic fins to lift itself off the surface and propel itself forward. (Photo: Yen-Chyi Liu/University of Chicago)

The researchers reported the lungfish demonstrated both “bounding” motions, where both limbs moved at the same time, and “walking,”  with the fish alternating use of its limbs to move forward.

These behaviors, along with  the ability to fully rotate its limb and to place each subsequent footfall in front of the joint, suggest to researchers that similar creatures, perhaps ancestors of the lungfish, would have been capable of producing some of the fossil tracks credited to tetrapods.

The group says its discovery suggests that many of the developments necessary for animals to make the transition from water to land may have taken place long before early tetrapods were able to take their first steps on land.

They believe the lobe-finned ancestors of the lungfish, as well as tetrapods, could be responsible for the evolution of hind-limb propulsion and the ability to walk at the bottom of a lake or marsh millions of years before the appearance of  land-dwelling animals.

The winner of the Nobel Prize in chemistry was announced this morning in Stockholm.

Daniel Shechtman of Technion, the Israel Institute of Technology, in Haifa, Israel, won for his 1982 discovery of quasicrystals.

Quasicrystals are unusual materials which have some of the properties of a regular crystal, but have a more elaborate and complex structure at the atomic level. This unique material does not conduct heat or electricity well and, because of this, the quasicrystals can be used in thermoelectric materials, which converts heat into electricity and vice versa.

The Nobel prizes for physics and physiology or medicine were also announced earlier this week.

The 2011 Nobel Prize in physics went to three people;  Saul Perlmutter from Lawrence Berkeley National Laboratory and University of California; Brian P. Schmidt of the Australian National University; and Adam G. Riess from Johns Hopkins University and the Space Telescope Science Institute.

By studying distant supernovae, or exploding stars, the three physicists discovered that our universe continues to expand at an accelerating rate, even after more than 14 billion years since the Big Bang.

This year’s Nobel Prize in physiology or medicine was awarded to the late Ralph M. Steinman for his discovery of the dendritic cell and its role in adaptive immunity; and to scientists Bruce A. Beutler and Jules A. Hoffmann for their discoveries concerning the activation of innate immunity.

Sadly, Ralph Steinman died from pancreatic cancer just three days before the announcement was made.

The Nobel Prizes for these science-based categories will be awarded in a ceremony to be held Dec. 10 in Stockholm, Sweden.

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Arctic ice continues to decline

NASA satellite data reveals how this year's minimum sea ice extent, reached on Sept. 9 as depicted here, declined to a level far smaller than the 30-year average (in yellow), opening up Northwest Passage shipping lanes (in red). (Graphic: NASA Goddard's Scientific Visualization Studio)

Arctic sea ice continues to decline; the summertime sea ice cover narrowly avoided a new record low, which was set back in 2007.

That’s according to satellite data from NASA and from the NASA-supported National Snow and Ice Data Center (NSIDC) at the University of Colorado in Boulder.

The Arctic ice cap grows each winter as the sun sets for several months, then shrinks each summer as the sun rises higher in the northern sky. The Arctic sea ice reaches its annual minimum extent each year in September.

NASA monitors and studies the changing sea ice conditions in both the Arctic and Antarctic regions with a variety of spaceborne and airborne research capabilities.

Joey Comiso, a senior scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md., says that not only is the sea ice declining, but the pace of the decline is also much more drastic.

Climate models constructed by researchers suggest the Arctic could lose almost all of its summer ice cover by 2100. However, they also found that that the ice extent has declined faster in recent years than their models had predicted.

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Green tea may slow weight gain

A cup of green tea

Green tea has become a popular beverage in recent years, most likely because of its many health benefits.  Now food scientists at Penn State University in State College, Penn., have found another reason to drink the brew;  it may slow down weight gain and serve as another tool in the fight against obesity.

Researchers fed obese mice Epigallocatechin-3-gallate (EGCG), a compound found in green tea, along with a high-fat diet. They found that the mice gained weight at a significantly slower rate than the control group mice, which didn’t get the green tea supplement

In addition to gaining weight at a slower rate, says Joshua Lambert, an assistant professor of food science in agricultural sciences at Penn State, the mice fed the green tea supplement showed a nearly 30 percent increase in fecal lipids, which suggests that the EGCG was also limiting fat absorption.

The researchers released their findings in the current online edition of the journal “Obesity.”

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Fish behavior could determine its fate

A bluegill fish (Photo: Tom Tetzner - U. S. Fish and Wildlife Service, Northeast Region

A fish’s personality could determine how likely it is to be caught or captured, according to Canadian researchers.

The Queen’s University in Ontario found that anglers who fished near rocky outcrops or in areas of water with submerged vegetation seemed more likely to catch timid fish who prefer safe, hidden habitats, while those fishing in open water were more likely to reel in bolder fish.

The researchers examined the personalities of bluegill sunfish which were caught  using two different capture techniques; angling, which is the traditional hook attached to a fishing line; and a method called beach seining, which involves dragging a long net through water to surround and ensnare fish.

Fish caught with the angling technique appeared to be more timid than fish captured by the beach seining method.

According to the research team, the differences they found in personalities of fish could have significant evolutionary and ecological consequences for affected fish populations, as well as for the quality of fisheries.

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(Photo: photos.com)

According to an old proverb,  the eyes are the windows of the soul.  They’re also  one of the most important accomplishments of evolution, nature’s perfect camera providing us with a vivid visual sense of the world around us.

However, did you ever wonder how the eye came to be? What caused the eye to be formed to begin with?  How did it evolve and develop to fit the specific needs for all current and past species on Earth?

Thanks to the curiosity of an ophthalmology professor at the University of California, Davis, we can read all about it in a new book called “Evolution’s Witness: How Eyes Evolved”.

Dr. Ivan Schwab wanted to find out how animals were able to see. As he got further into his research, he realized he also wanted to learn about the origins of the eye itself and how it developed through years of evolution.

So how did it begin?  What was the stimulating factor that set off what would become the eye?  Dr. Schwab simply points to the sun and the energy its produces.

“The eye didn’t start as an eye as we know it, for sight,” he says.

Indeed, what would become the eye first started as the means for transferring the sun’s energy into energy for the cells.

“This was done by a variety of molecules… the best one is related to Vitamin A, the same vitamin you get from carrots or mangoes,” according to Dr. Schwab. “That particular chemical will transform the light rays of the sun into energy for the cell so that it can perform its internal mechanics.”

When the first eye, as we know it, appeared is kind of a guessing game, says Dr. Schwab, since the eye doesn’t fossilize most of the time due to its soft parts. The eye gradually evolved into an organ capable of seeing light and dark and perhaps some form.

Dr. Schwab imagines that the first real eye saw very poorly, registering blurry images and used, perhaps, to find where to capture energy or locate enemies.

Once eyes appeared, they evolved in different ways, developing into at least 10 to 12 varied forms. Each species’ eyes are developed into one that fits its specific niche.

One example is the the marine crustacean, the stomatopods, or mantis shrimp. Dr. Schwab says, since this creature tends to live near coral reefs, it has eyes with more color receptors than we have. As a result, they can see more colors than we can – 16 pigments compared to the three pigments humans can detect.

The human eye is referred to as camera-style eye since its mechanics resemble those of a film-loaded camera.

Dr. Schwab describes them as a sphere with a front element called the cornea. Another element is the lens, which does the focusing. The back of the eye, or retina, creates the visual image that is delivered to the brain.

Another type of eye style is the telescopic eye.

As an example, Dr. Schwab cites the “jumping spider.” Jumping spiders have excellent vision, with one of the highest acuities among invertebrates.  Its eyes are small and compact, utilizing telephoto-type optics to maximize its vision.

Since this spider can’t move its eyes externally, like we can, it must do so internally.

“It’s like a raster scan on your TV,” says Dr. Schwab. “It lays out a line of dots,  another line, another line, until it’s formed a whole image, but, of course, it does so rapidly.”

Dr. Schwab says that, although eyes will continue to evolve, the eyes of many species are already at a mature level so they’re not going to evolve much further in terms of the optics themselves.  So where our eyes or vision will improve, speculates Dr. Schwab, is probably in the interpretation of the visual signals the eye produces.

Dr. Schwab, joins us this weekend on the “Science World” radio program to talk about his new book, the eye’s first appearance and its subsequent evolution and development.

>>>> Listen to the interview here…

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Other stories we cover on the “Science World” radio program this week include:

• Warning sounded on dangers of arsenic in India’s groundwater
• Study: Female coffee drinkers are less depressed
• China launches first module of future space station
• South Korean weather forecasters tell you when you’ll catch a cold
• Reducing an invasive species while fighting hunger at the same time
• Whew! NASA finds fewer ‘planet-buster’ asteroids than predicted

An illustration of how Acherontisuchus guajiraensis, a 60-million-year-old ancestor of crocodiles, would have looked in its natural setting.  You can also see titanoboa (world's largest snake) in the upper left side of image. (Danielle Byerley, Florida Museum of Natural History)

The fossilized remains of a 60-million-year-old, long-extinct, freshwater relative to the modern crocodile have been found by University of Florida researchers.

The 20-foot-long, fish-eating ancient crocodile is believed to be the first known land animal from the Paleocene New World tropics. It was discovered in the same northeastern Colombian coal mine as titanoboa, the world’s largest snake.

While these two creatures probably competed for the same food, researchers believe the huge super-snake, which had a more generalized diet than the crocodile, could easily have feasted on the croc’s young, too.

This photograph shows the size difference in the jawbones of two 60-million-year-old crocodile ancestors found in northeastern Colombia - (Photo by Kristen Grace/ Florida Museum of Natural History)

By the way, the titanoboa’s remains were found in 2009. They measured up to 15 meters in length and weighed about 1,135 kilograms.

This new species – called Acherontisuchus guajiraensis – is from the dyrosaurid family of extinct neosuchian crocodyliforms.

It was named for the river Acheron (“the river of woe”) from Greek mythology, since the animal lived in a wide river that emptied into the Caribbean.

Alex Hastings, who led the study, displays a pelvic bone of  a 60-million-year-old ancestor of the modern crocodile. (Photo by Kristen Grace/Florida Museum of Natural History)

The newly-discovered fossils of a partial skeleton of this species reveal that the dyrosaurids were quite important and influential in northeastern Colombia.

Paleontologists also believe diversity within this reptilian family evolved along with a number of environmental changes, such as an asteroid impact or the appearance of competitors from other groups.

The discovery of the ancient crocodile species is discussed in a new study in the journal “Paleontology.”

The study’s authors say this discovery should give scientists a better understanding of the diversity of animals that inhabited the oldest known rainforest ecosystem, which was much hotter than the rainforests of today. It could also prove useful in helping us better understand the impact of a warmer climate in the future.

The ancient crocodile had a long, narrow snout  full of pointed teeth.  According to scientists, these physical characteristics allowed the new species to specialize in hunting lungfish and relatives of bonefish, which inhabited the water of their habitat.

Recently discovered microfossils are believed to be the oldest ever found on Earth. (Photo: Dr David Wacey of the University of Western Australia)

Researchers from England and Australia recently found some microfossils in a remote part of Western Australia.

Before you click away and say, “Big deal another fossil find,” hang with me for a bit.

The microscopic fossils, according to the researchers, are 3.4 billion years old, making them Earth’s oldest fossils.

The fossils resulted from life forms which lived on our planet before Earth even had oxygen.

Wow!  Kind of hard to visualize Earth without its life-giving oxygen, isn’t it?

OK, lets step back to the time when Earth first formed.

Most scientists generally agree that our planet is between 4.5 and 4.6 billion years old.

Soon after being formed, Earth was a huge molten hunk of rock with no atmosphere and, of course, none of the characteristics that make our planet special.

Illustration of the inner earth (Image: Lawrence Livermore National Labs)

At this time, Earth’s core was also still forming. There was no solid inner core or  liquid outer core, like there is today, so the world wasn’t able to retain gasses very well.

Scientists describe our first atmosphere as being composed of hydrogen and helium, two elements which were very common when Earth and the rest of the solar system were formed.

Because of the heat and unformed core, these gasses soon escaped from Earth into space.

Earth continued its cooling process and, as the core began to stabilize, the earth’s magnetic fields were formed.

A more stable core and a cooler planet meant that more of the gasses produced by our evolving world could be retained closer to its surface.

As volcanic activity began and continued to increase throughout the planet, a lot of different gases formed as a result.

These included carbon dioxide (CO₂), carbon monoxide (CO), sulfur dioxide (S₂), chlorine (CL₂), nitrogen (N₂), deuterium, also called heavy hydrogen (H₂), ammonia (NH₃) and methane (CH₄).

The volcanoes also produced a lot of steam (water/H₂O), but no free existing oxygen (O₂).

Oxygen was later produced and introduced into our atmosphere through two processes; photochemical dissociation, caused by the breakup of water molecules by the sun’s ultraviolet light, and photosynthesis, the process that uses carbon dioxide and water (H₂O) to form organic compounds while also releasing oxygen (O₂).

Early forms of life that developed and lived during this “pre-oxygen time”, some 3.4 billion years ago, were sulfur-based cells and bacteria which lived off metabolized compounds which had sulfur, rather than oxygen, for energy and growth.

According to researchers, these microscopic fossils are 3.4 billion years old. (Photo: Dr David Wacey of the University of Western Australia)

The researchers, from the University of Western Australia and England’s  Oxford University,  say their discovery of these microfossils provides convincing evidence that these unique early life forms did exist.

Oxford Professor Martin Brasier, one of the team’s leaders, says the life forms of the fossils still exist and are common today.

The sulfur-based bacteria can be found in smelly ditches, soil, hot springs, hydrothermal vents – anywhere there’s little free oxygen and they can live off organic matter.

Professor Brasier says their discovery also has implications in the search for life on other planets, giving scientists an indication of what evidence for such life might look like.

A report on this finding can be found in the journal Nature Geoscience.

Charles Darwin

Do certain species survive at the expense of others? The question of competition between the species was at the heart of a premise first explored by Charles Darwin in 1859. A new study lends further support to this aspect of Darwin’s still-controversial theory of natural selection.

Darwin’s  “On the Origin of Species by Means of Natural Selection” outlined a revolutionary approach which would eventually become known as evolutionary biology.  Today, more than a century later, scientists continue to try to either prove or disprove Darwin’s theories.

One of Darwin’s hypotheses explored the role  competition played in determining the survival of a species.  A recently released study led by Lin Jiang at Georgia Institute of Biology – otherwise known as Georgia Tech – supports this theory.

Although most scientists already tend to accept Darwin’s premise, this new study presents the strongest direct experimental evidence yet to support its validity.

Dr. Jiang’s team chose to study 10 common species of the ciliated protist – or protozoa microrganisms – because of their ability to reproduce. This allowed the research team to examine the co-existence of the species over multiple generations in just a few weeks.

The research team conducted their experiments within specially constructed, artificial and simplified ecosystems called microcosms.

When left alone in a microcosm, all of the species survived until the end of the experiment. However, when two species were paired together, one dominated in more than half of the experiments, leading to the extinction of the other species.

The team found that extinction occurred faster and more often between the species of  microorganisms that were more closely related. Dr. Jiang says this aspect of the study supports Darwin’s theory, referred to as the phylogenetic limiting similarity hypothesis.

This hypothesis is just one of the many Darwin published in “The Origin of Species.”  It was through this book that Darwin introduced the scientific theory that populations evolve over the course of generations through a process of natural selection.

This weekend on the “Science World” radio program, Dr. Jiang explains this hypothesis and talks to us about his team’s research and what else they learned from their studies.

Listen to the interview here…

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Other stories we cover on the “Science World” radio program this week include:

• Final mission of the Space Shuttle program is under way
• Drug used to treat head lice might also curb the spread of malaria
• President Obama holds first Twitter Town Hall meeting
• Oil spill on Montana’s Yellowstone River spikes concern over pipeline safety
• Early CT scans boost survival rates for smokers with lung cancer

This is one of the Tagish Lake meteorite fragments. (Photo: Michael Holly, Creative Services, University of Alberta)

Can life on Earth be traced to asteroids that crashed into our planet over the millenia?

A recent research project provides evidence to support that theory.

The study indicates that Earth-bound asteroids not only delivered the life-starting organic compounds, but also that these compounds evolved over time.

A research team, led by University of Alberta geologist Chris Herd, examined and analyzed one of the most pristine meteorites ever recovered and found that the composition of the organic compounds it carried had changed during the early years of the solar system.

These modified organics were then preserved for billions of years in outer space before the meteorite crashed to Earth.

The meteorite the team studied was one that fell near Tagish Lake in northern British Columbia in 2000.

Upon initial examination, the researchers found that variations in the geology of the meteorite samples were visible to the naked eye which, to them, indicated that the meteorite’s originating asteroid had gone through some substantial changes.

After examining these geological variations, the researchers turned their attention to looking for variations in the meteorite’s organic chemistry. Dr. Herd says that the researchers were then able to get a glimpse of the process that altered the composition of organic material carried by the asteroid.

Among the organic compounds found on the meteorite were amino acids and monocarboxylic acids, two chemicals believed to be essential to the evolution of the first simple life forms on Earth.

This weekend on the “Science World” radio program, Dr. Herd talks about this study and why he thinks that this finding shows the importance of asteroids to Earth’s history.

Listen to it here…

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Other stories we cover on the “Science World” radio program this week include:

• NASA readies Atlantis for final shuttle flight ever
• Can city living lead to mental illness?
• What’s in a name? Big changes ahead for the Internet
• When non-native species are harmful invaders
• Reducing HIV among gay men and transgendered people