Nov 16, 2013

Cancer Doctor Under Fire for Unproven Treatment

Stanislaw Burzynski, a doctor whose unorthodox cancer therapies have been touted for decades, has come under fire for providing false hope to patients. Burzynski, who has been treating patients in his private Houston clinic since 1977, has some prominent supporters, including TV’s “Dr. Oz” and a documentary filmmaker who has created two films championing his cause and treatments. But most doctors and cancer centers claim that Burzynski is profiting from preying on the sick and vulnerable.

Because his treatments have not been proven effective, most medical insurance will not cover them and patients are often asked to pay for his services up front—as much as $20,000 to start and $7,500 per month thereafter to continue. There are several aspects about Burzynski’s practice that have raised red flags, including that he claims a cancer cure success rate far higher than other therapies, and that he is not a trained oncologist yet claims to have made amazing breakthroughs in oncology. Specifically, he claims that cancer can be caused by a patient’s lack of antineoplastons (a naturally-occurring compound found in blood and urine), a finding that no other cancer researchers have been able to verify.

In fact, according to a news story in “USA Today,” “the National Cancer Institute says there is no evidence that Burzynski has cured a single patient… He has not backed up his claims by publishing results from a randomized, controlled trial — considered the gold standard of medical evidence — in a respected, peer-reviewed journal. And Burzynski’s drugs pose a risk of serious harm, including coma, swelling near the brain and death, according to the NCI and informed consent documents that patients sign before beginning treatment. While Burzynski has touted his treatments as an alternative to chemotherapy, a 1999 NCI study found that antineoplastons can cause many of the same side effects as conventional chemo: nausea, vomiting, headaches, muscle pain, confusion and seizures.”

In fact not only has Burzynski failed to publish a single study of his “breakthrough” research in medical journals, but according to the U.S. National Institutes of Health, he has completed exactly one of the over 60 medical studies he has begun over the years. If his therapy is as successful as he claims, it is curious that there appears so little research to back it up. The status on virtually all of his studies are “unknown” or “withdrawn,” meaning that there are no results to report and therefore no evidence that his miracle therapy is effective.

Cult of Personality

Dr. Stanislaw Burzynski is no newcomer to alternative medicine. According to Dr. David Gorski of the Science-Based Medicine blog, “Dr. Burzynski first gained fame for his cancer therapy back in 1988, when ‘Sally Jesse Raphael’ featured four ‘miracle’ patients of Burzynski’s, who, according to her, had had incurable cancer and failed conventional therapies but were rendered cancer-free, thanks to Dr. Burzynski. Unfortunately, four years later in 1992, ‘Inside Edition’ followed up these four patients and found that two of the four had died and a third had recurred, while the fourth had had bladder cancer with a good prognosis. In that report, the widow of one of Raphael’s guests reported that her husband and five others had sought treatment from Burzynski and that all had died.”

Though doctors and cancer centers are unimpressed (if not alarmed) by Burzynski work and research, he has many defenders, some of them very passionate. Part of the reason he is so popular is that he has become something of a cult figure, feeding on conspiracy theories and anti-Big Pharma sentiment. He is portrayed in many profiles as a misunderstood maverick doctor trying to help people despite being rejected by “the medical establishment” as too radical.

Read more at Discovery News

Nature Pulls a Fast One On Astronomers: Two Galaxies Caught Masquerading as One

What might look like a colossal jet shooting away from a galaxy turns out to be an illusion. New data from the National Science Foundation's Karl G. Jansky Very Large Array (VLA) reveal that two galaxies, one lying behind the other, have been masquerading as one.

In a new image highlighting the chance alignment, radio data from the VLA are blue and infrared observations from NASA's Spitzer Space Telescope and Wide-field Infrared Survey Explorer (WISE) are yellow and orange, respectively. Visible data are also shown, with starlight in purplish blue and heated gas in rose.

The closer galaxy, called UGC 10288, is located 100 million light-years away. It is spiral in shape, but from our viewpoint on Earth, we are seeing its thin edge. The farther galaxy, seen in blue, is nearly 7 billion light-years away. Two giant jets shoot away from this galaxy, one of which is seen above the plane of the closer galaxy's disk.

Earlier radio images of the two galaxies appeared as one fuzzy blob, and fooled astronomers into thinking they were looking at one galaxy. Thanks to the VLA pulling the curtain back on the disguised duo, the scientists have a unique opportunity to learn otherwise-unobtainable facts about the nearer galaxy.

"We can use the radio waves from the background galaxy, coming through the nearer one, as a way to measure the properties of the nearer galaxy," said Judith Irwin, of Queen's University, Canada, lead author of a recent paper on the findings, appearing online Nov. 15 in the Astronomical Journal.

Observations from Spitzer and WISE helped to reveal new structures above and below the plane of the closer galaxy's disk. For example, Spitzer helped confirm an arc-like feature rising more than 11,000 light-years above the disk, which was seen in the radio observations.

Irwin worked with an international team of astronomers from North America, India and Europe who are part of the "Continuum Halos in Nearby Galaxies -- an EVLA Survey" (CHANG-ES) consortium.

The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology in Pasadena. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, Colorado. Data are archived at the Infrared Science Archive housed at the Infrared Processing and Analysis Center at Caltech. Caltech manages JPL for NASA. For more information about Spitzer, visit http://spitzer.caltech.edu and http://www.nasa.gov/spitzer .

Read more at Science Daily

Nov 15, 2013

This Shrew Can Survive You Standing on It (Maybe. Please Don’t Try)

In 1910, a pair of scientists exploring what is now the Democratic Republic of Congo came across a shrew of improbable furriness and size (though it still weighed in at just a tenth of a pound). Locals identified it as the hero shrew, whose bones, pelt, and even ashes granted invincibility when carried into battle.

To prove the shrew’s powers, a grown man grabbed one, placed it on the ground, and stood on it for several minutes — a performance I’ve unremorsefully decided to dub The Maiming of the Shrew. When the man stepped off, the creature hesitated briefly with “a few shivering movements” before scurrying away, “none the worse for this mad experience and apparently in no need of the wild applause and exhortations” of the gathered crowd.

Yeah, spines aren’t supposed to look like this. Unless you’re a hero shrew. Then it’s normal.
This account, which appeared in the Bulletin of the American Museum of Natural History, raises a few questions, foremost of course being, what kind of scoundrel would be the first to see if he could stand on this animal for several minutes without killing it? And how many different critters did he try this on before finding success with the hero shrew? A perhaps more important and more answerable question might be, how on Earth could a 6-inch-long creature survive such trauma?

Also known as the armored shrew, the hero shrew derives its powers from an absolutely incredible backbone, which is so wildly different from any other vertebrate’s that it looks like the prankish creation of some bored scientist, à la the fantastical “specimens” of the jackalope or the Fiji mermaid. And while no respectable researcher would recreate the aforementioned test of the backbone’s strength, we can say with confidence that this is the animal kingdom’s most remarkable spine.

Feel the back of your neck. Notice the bump at the base? It’s called a process, and it’s the part of your vertebrae that muscles and ligaments attach to. Most vertebrates, including us, have that single process at the top of each vertebra and a few others on either side.

But the hero shrew has an astounding 10 to 20 processes per vertebra, according to William Stanley, collection manager of mammals at Chicago’s Field Museum, “and they interlock with the processes to the front and to the back of each vertebra so that you have this very ornate, intricately digitated series of backbones that give these animals incredible strength.”

According to Stanley, its spine is, relative to body size, four times more robust than that of any other vertebrate, which poses quite the evolutionary conundrum: This is a singular species whose backbone is miles away from its shrew cousins. There’s a more typical shrew at one extreme and then the hero shrew at the other, with no species in between. This might suggest that the evolution of the robust spine was supremely rapid and dramatic, an evolutionary principle known as punctuated equilibrium, because there are no intermediate forms between the two to indicate a more gradual development.

But then Stanley traveled to the Congo in 2012 to study disease transmission in rodents and found his own shrew. It wasn’t until he brought the specimen back to the Field Museum and analyzed its DNA that he discovered that it was in fact a hero shrew — only a bit different. A dissection revealed a somewhat less robust spine, and it became clear that Stanley may have discovered an intermediate species.

Shrew spines from left to right: Scutisorex somereni (original hero shrew), Scutisorex thori (Thor’s hero shrew), and Crocidura olivieri (a more “normal” African giant shrew). Please note that those numbers do not appear naturally on shrew skeletons. They were added by a human with a permanent pen.
The new form has seven or eight vertebrae in its lumbar region to the original hero shrew’s 10 or 11 (and our five), with about half the processes sticking out of the sides of each. And while they also interlock, they’re a bit broader. Stanley named it Thor’s hero shrew after the man who inspired his work in mammalogy, Cal State Humboldt’s Thor Holmes, who just so happens to share his name and magnificent beard with the Norse god of strength.

“This new species exhibits features that could be intermediate,” said Stanley. “That’s not to say that they are. One possibility is that there was a punctuated equilibrium event where there was the standard shrew backbone and then suddenly the first discovered hero shrew evolved out of that. And this form that we just found subsequently evolved from that.”

So now we know of at least two species of hero shrews with freakishly robust spines, but then we inevitably come to the why. Why evolve such an impressive backbone? (After all, it “certainly wouldn’t serve to just carry people around,” said Stanley.)

After discovering Thor’s hero shrew, Stanley recalled a conversation he’d had 15 years earlier with a colleague, Lynn Robbins, who had not only come in contact with the original hero shrew during his time in Africa, but had formulated a theory for the purpose of its spine.

Robbins had watched locals yank dead palm leaves off trees in search of hidden beetle grubs, and it was in these palm forests where hero shrews seemed to proliferate. He theorized that the shrews hunt the same grubs in much the same manner, squeezing themselves between the leaves and the trunk of the tree and literally putting their backs into it to leverage the fronds and get at the quarry.

Read more at Wired Science

Old Dog, New Origin: First Pooches Were European

Man's best friend gained that title in Europe, according to a new study that pinpoints the origin of dog domestication to between 18,800 and 32,100 years ago.

The study places the origin of dogs before the rise of agriculture, suggesting that human hunter-gatherers tamed the wolf. Whereas previous genetic studies had placed the origin of dogs in the Middle East or Asia, this research is the first to focus on the genetics of ancient dogs, rather than looking at modern dogs and trying to extrapolate back.

"All modern dogs analyzed in our study were closely related to either ancient dogs and wolves from Europe or modern wolves from there," study scientist Olaf Thalmann, a postdoctoral researcher at the University of Turku in Finland, told LiveScience in an email.

The beginning of dogs

Dogs are the only large carnivores that humans have ever domesticated, but when and where dangerous wolves became lovable pups has been hard to pin down.

That's because, genetically speaking, dogs are a mess. They've been moved around the world for centuries, mixing their genomes indiscriminately at far-flung ports of call, and even -- early in their evolution -- mating with their wild counterpart, the wolf. Adding to the confusion is the intensive period of selective dog breeding that started in the late 1880s and gave humans the wide variety of dog breeds known today.

Archaeologists have found definite evidence of domestication in the form of dogs and humans buried together at least 14,000 years ago. Some have suggested domestication occurred earlier than that, perhaps as long as 33,000 years ago, based on some doglike skulls found in Belgium and in Siberia.

Original genetic analyses put dog domestication much earlier, with researchers writing in a 1997 paper in the journal Science suggesting that dogs diverged from wolves more than 100,000 years ago.

Those studies compared modern dogs with modern wolves. However, the analysis was muddied by dogs' weird breeding history. In the new study, published Friday (Nov. 15) in the journal Science, scientists analyzed ancient DNA from prehistoric dog fossils found in Europe and the New World.

Genetic ties

The researchers sequenced mitochondrial DNA from these fossils. Mitochondria are tiny organs inside cells that generate the energy that cells need to run. The genes that control the mitochondria are passed down the maternal line.

Comparing the ancient mitochondrial DNA with the mitochondrial DNA of modern dog breeds and wolves revealed a common link to Europe, the researchers found.

"Dogs seem to have been domesticated or first evolved from a population of ancient wolves living in Europe," said study researcher Robert Wayne, a professor of ecology and evolutionary biology at the University of California, Los Angeles. "That ancient wolf population is now extinct."

"We've kind of made mistakes [in previous studies] assuming that ancient wolves and modern wolves are direct ancestors and descendants," Wayne told LiveScience.

The finding suggests that wolves first started hanging around humans during a time when people hunted large animals like mammoth. The remains of mammoth and other megafauna carcasses would have been good eating, and friendlier wolves may have gradually started interacting with the human hunter-gatherers.

The study researchers also examined some of the most controversial prehistoric canid fossils, including one found in a cave in the Altai Mountains of Siberia and others discovered in Belgium. These remains date as far back as 36,000 years ago. The new study finds that the Siberian and Belgian pooches were not direct ancestors to modern dogs. It seems they may have been an unknown species of doglike wolf, or they may have been an "aborted domestication event," Wayne said.

A European story

Genetics is a tricky way to try to establish the timing of dogs' emergence, said Clive Wynne, a dog cognition researcher at Arizona State University who was not involved in the study. Many of the genetic techniques used were developed to trace the divergence of species over millions of years. Dog domestication happened much more quickly, and a few thousand years makes a big difference in whether dogs were originally the pets of hunter-gatherers or more sedentary farmers, Wynne told LiveScience.

Most researchers already agreed that the rise of dogs occurred before the rise of agriculture, said Greger Larson, an archaeologist and geneticist at Durham University in the U.K. who was not involved in the study. But the new geographical information linking dogs to prehistoric Europe is "a really big step in the right direction," Larson told LiveScience.

"What it absolutely establishes is that there are canids in Europe that are contributing DNA to modern dogs and that Europe is, without question, part of the story," Larson said. "Zooarchaeologists and archaeologists have known that for a long time, but the genetic data has not backed that up."

Read more at Discovery News

1st-Century Roots of 'Little Red Riding Hood' Found

Folktales can evolve much like species do, taking on new features and dropping others as they spread to different parts of the world.

One researcher in the United Kingdom tested this analogy quite literally, using analytical models that are typically used to study the relationships between species to create an evolutionary tree for "Little Red Riding Hood" and its cousins.

"This is rather like a biologist showing that humans and other apes share a common ancestor but have evolved into distinct species," Durham University anthropologist Jamie Tehrani explained in a statement. Tehrani found that "Little Red Riding Hood" likely branched off 1,000 years ago from an ancestral story that has its roots in the first century A.D.

"Little Red Riding Hood" is well known to Westerners thanks to the Brothers Grimm. In the story, a girl visits her grandmother's house only to be greeted by a wolf disguised as the old woman. Little Red Riding Hood is promptly devoured after remarking "What big teeth you have, Granny!" But a lumberjack later cuts open the wolf and saves the girl and her grandmother who are miraculously still alive in the beast's stomach.

But there are several other versions of this story from ancient European oral traditions, including variants in which the girl outwits the wolf and escapes after asking to go outside to use the toilet. In another story dubbed "The Wolf and the Kids," which has been told throughout Europe and the Middle East, a nanny goat goes out in the field but first warns her kids not to open the door. A wolf who overhears her warning impersonates the nanny goat, tricks the kids into letting him inside and eats them.

Similar tales also pop up in oral traditions in Asia and Africa. There's "The Tiger Grandmother" in East Asia, for example, in which a group of children unwittingly spend the night in bed with a tiger or monster dressed as their grandmother. After the youngest sibling is eaten, the children get the monster to let them outside to use the toilet and they escape.

To investigate the possible relationships between these tales, Tehrani looked at 58 variants of the story, focusing on 72 plot variables, such as the number and gender of the protagonists, the ending, and the type of animal or monster that becomes the villain.

Tehrani used phylogenetic models — or models that probe the evolutionary relationships among species through time — to compare similarities between these plot variables and determine the probability that they came from the same source. The result is a tree that shows how the story may have evolved.

Tehrani discovered that "Little Red Riding Hood" seems to have descended from the more ancient story "The Wolf and the Kids" — but so did African versions that independently evolved to look like "Little Red Riding Hood."

"This exemplifies a process biologists call convergent evolution, in which species independently evolve similar adaptations," Tehrani explained in a statement. "The fact that Little Red Riding Hood 'evolved twice' from the same starting point suggests it holds a powerful appeal that attracts our imaginations."

The analysis also suggests that the Chinese version of "Little Red Riding Hood" derives from ancient European tales and not vice versa as other researchers have suggested.

Read more at Discovery News

Taking a Closer Look at Mysterious Pluto

In July 2015, we will see some of the most monumental photos of spaceflight history. NASA’s New Horizons probe will blast through the Kuiper belt, imaging the region beyond Neptune’s orbit and gathering an intimate view of the Pluto-Charon system. But until that fateful flyby, we will have to make do with fuzzy observations of the distant dwarf planet, although a surprising amount of detail can still be gathered by powerful telescopes and rendered by sophisticated models.

Enter the Scientific Exoplanets Renderer (SER) as used by Abel Méndez, planetary scientist and director of the Planetary Habitability Laboratory at the University of Puerto Rico, to create a very cool view of the small, yet complex world.

SER is more commonly used to generate photo-realistic images of exoplanets, renderings of which can be found in the Visible Paleo-Earth project and the Habitable Exoplanets Catalog. By gathering as much observational data about planets orbiting other stars as possible — such as data from the complex light-curves of transiting exoplanets — and feeding the SER, artistic renderings based on real observations can be generated. The more data available, the more precise the model.

So, looking a little closer to home, Méndez applied SER to Pluto. By feeding the algorithm with albedo data from the Hubble Space Telescope, he generated a “basic representation” of Pluto. For now, the model only uses albedo maps from Hubble (i.e. the brightness variations as mapped across Pluto’s surface), but Méndez plans to “produce more creative” versions, adding more detail to the apparent surface features.

“It will be fun to compare our progress, starting from our first image, until the final close-up pictures of Pluto on July 2015,” writes Méndez.

Interestingly, Méndez applied the same color palette as used to color observations of Triton, Neptune’s strange moon. Triton has a retrograde orbit around the ice giant (i.e. it orbits in the other direction to all the other 13 known Neptunian satellites) and has a very different composition leading planetary scientists to theorize that it is actually a captured Kuiper belt object and a close cousin to Pluto. Therefore there’s every reason to believe that we will spot some uncanny similarities between Pluto and Triton when seen up close.

In the run-up to the New Horizons flyby, there will be lots of opportunities to refine the model with new data.

Although he has yet to evaluate the SER Pluto model, New Horizons Principle Investigator Alan Stern, planetary scientist at the Southwest Research Institute, is keen to point out that as the spacecraft approaches the outer solar system observations of Pluto will become more and more detailed, inevitably enriching models like Méndez’s visualization.

Read more at Discovery News

Nov 14, 2013

Ocean Glow Stick: Sea Worm Emits Strange Glow

One common sea worm has a rather uncommon trick: Chaeteopterus variopedatus -- also known as the parchment tube worm for the paperlike tubes it builds for itself and lives within throughout its life -- secretes a bioluminescent mucus that makes it glow blue.

Now, scientists are a step closer to understanding the mechanisms behind the worm's glow.

The parchment tube worm can be found on shallow, sandy seafloors all around the world. Its glow sets it apart from other tube worms, most of whichdon't glow, and other shallow water organisms, which typically emit green light, not blue.

Green light is more typical of shallow-water bioluminescence because it travels farther than any other color on the light spectrum, a useful quality in the turbid near-shore environment.

"Shallow water is much more complex than deep water from a physical standpoint, and green is what organisms see best," Dimitri Deheyn, a biologist at the Scripps Institution of Oceanography involved in the research, told LiveScience's OurAmazingPlanet. "If you produce light and you want light to be associated with an ecological function, you want organisms to see it."

Researchers have known about the unusual blue-glowing worm for decades, but nobody has ever looked closely at its light-emitting properties. Now, Deheyn and his colleagues have conducted two new studies that help characterize it.

First, the team found that, unlike light-emitting mechanisms in many other organisms, the worm does not require oxygen.

Light production usually occurs when two chemicals react together with oxygen to produce a compound that then produces light, Deheyn said. In past studies, researchers have found that glowing stops in the absence of oxygen.

But when Deheyn's team removed oxygen from the tube worm, the worm continued glowing. They reported these findings last month in the journal Physiological and Biochemical Zoology.

"In our case, if you remove oxygen, you don't stop the light," said Deheyn. "So the biochemical pathway that eventually leads to light production does not follow conventional characteristics."

In a separate experiment, the team found that riboflavin -- also known as vitamin B2 -- plays an important role in the worm's light production, but its exact role remains unclear. However, since the worms do not produce riboflavin on their own, they must be acquiring their glowing properties from their diet or from symbiosis with bacteria, the researchers recently reported in the journal Photochemistry and Photobiology.

Read more at Discovery News

Did Early Life Build Earth's Continents?

Earth's earliest life forms could be responsible for the creation of much of the dry land we live on today, according to a new geophysical model of the evolution of Earth's crust and mantle.

On its face, the claim seems a bit outrageous, but this is how it works: Early life on land might have led to a lot more erosion, which dumped a lot more wet sediments into the deep trenches at subduction zones – those places where one tectonic plate is being shoved under another. When all that mud got mixed into the Earth's mantle, the trapped water dramatically livened up the geochemistry down there and caused a lot more volcanoes and granites to rise up through the crust, building more thick continental landmasses.

The bottom line is that when a team of German researchers modeled early Earth's mantle and crust with and without the potential added erosion caused by roots, bacteria, lichens and other biological agents of erosion, the planet evolved with less continental area – giving us a more watery world like that thought to have existed before the advent of life. Coming to this conclusion was not easy, however, because there aren't a lot of useful numbers they could plug into the model regarding how much living things are adding to the sediments pouring into subduction zones today.

“Altogether, it is very difficult to obtain a global value for the biological enhancement of weathering and erosion,” explained Dennis Höning of the Institute of Planetary Research in Berlin, Germany. “Also, the estimations which can be found in the literature vary from nearly no influence up to an enhancement of magnitudes. In our model, we decided to vary the erosion rate to obtain general tendencies.”

The role of water in the Earth's mantle is critical to the model, which is explained in the paper in the journal Planetary and Space Science by Höning and colleagues Hendrik Hansen-Goos, Alessandro Airo and Tilman Spohn. The model suggests that as Earth approached its one-billionth birthday, it was approaching a fixed point where it would have a small continental area and a dry mantle. Then life started messing with the geochemistry of the planet, revving up the mantle with more water and drove the planet to another fixed point with a lot more land area.

The work is part of a broader movement to better understand how life and water have fundamentally changed the evolution of the Earth.

“The list of elements that you can see affected by biology is increasing," said geologist Norman Sleep of Stanford University. Seismic reflection studies in recent years have backed up the idea that a lot of water is getting into the mantle via subduction zones and the geochemical signatures of that water and the life that helped it reach the mantle are in the rocks that rise from the wet mantle. "Biology has a way,” said Sleep. “It's not fully understood yet.”

Read more at Discovery News

Who Was Throwing Spears Before Humans?

Remains of the oldest known stone-tipped throwing spears, described in a new paper, are so ancient that they actually predate the earliest known fossils for our species by 85,000 years.

There are a couple possible implications, and both are mind-blowing. The first is that our species could be much older than previously thought, which would forever change the existing human family tree.

The second, and more likely at this point, is that a predecessor species to ours was extremely crafty and clever, making sophisticated tools long before Homo sapiens emerged.

Homo heidelbergensis, aka Heidelberg Man, lived in Africa, Europe and western Asia from at least 600,000 years ago. He clearly got around, and many think this species was the direct ancestor of Homo sapiens in Africa and Neanderthals in Europe and Asia.

The new paper, published in the latest PLoS ONE, focuses on the newly identified stone-tipped spears, which date to 280,000 years ago. They were found at an Ethiopian Stone Age site known as Gademotta.

Sahle, a postdoctoral researcher at the University of California at Berkeley’s Human Evolution Research Center, and his team analyzed the weapons. They determined that the spears were made from obsidian found near the site. The toolmakers had to craft the pointy spearhead shapes and spear shafts. They then needed to attach the points securely to the shafts. Even today, all of this would require skill, concentration and multiple steps.

Could a Steve Jobs-like innovator within the Heidelberg Man set have come up with this useful tool and production process?

Possibly, according to Sahle.

"Technological advances were not necessarily associated with anatomical changes (among Homo species)," he said. "The advances might have started earlier."

The intelligence needed to create such tools could therefore have predated our present body type. Based on the recreations I've seen of Heidelberg Man (and Heidelberg Woman), they did look very much like us. They were known to have been fairly tall and muscular.

As for why innovative tools from this period are known only from this site in Ethiopia, Sahle has some ideas.

"High-quality raw materials were nearby, so those could have allowed for the full expression of technological skills," he said.

"Second, a bigger population was supported at the site," he continued. With more individuals around, there would have been a greater chance for the spread of innovative ideas. If there was indeed a Steve Jobs-type in the mix, he would have been able to influence more individuals and perhaps even created a prehistoric spear-making assembly line of sorts.

"Thirdly, there was a mega lake at the site," Sahle said. "It might have attracted stable occupations there, further fueling technological advances."

Read more at Discovery News

The First Aliens We Discover May Be Purple

In our quest to discover strange new life on strange new worlds, a group of astronomers has modeled potential alien worlds using Earth’s biological history as a framework. From this they have determined that if we are to detect extraterrestrial biology, we should fine-tune our search to the color purple.

As we discover more and more worlds orbiting other stars in ever more biologically-pleasing orbits, the question “are we alone?” becomes increasingly acute. It’s inevitable that we will soon discover an alien world with Earth-like dimensions, orbiting a sun-like star within its habitable zone. But until we develop the means to remotely probe that world’s atmosphere, we can never be sure if it is truly habitable.

Looking for a “true” Earth analog is fraught with challenges. Are we looking for a planet with the same characteristics as modern Earth, or do we try to model our planets during different epochs and work out when Earth life would have been at its most detectable? Life on Earth has been around for the best part of 4 billion years, when would have been best for an alien civilization to detect terrestrial life and what would they have needed to look for?

It’s exactly this question that an international team of researchers is trying to answer.

“Clearly what we know about our planet will be our guideline for the characterization of (small rocky worlds in the habitable zones of their stars),” writes the team, headed by Esther Sanroma of the Instituto de Astrofísica de Canarias (IAC), Spain, in a paper accepted for publication in the Astrophysical Journal. “But the Earth has been inhabited for at least 3.8 (billion years), and its appearance has changed with time.”

3 billion years ago, during the Archean eon, the Earth was likely dominated by purple bacteria, a photosynthetic microorganism that inhabited the land and ancient seas. These organisms would have had a very distinctive spectroscopic fingerprint and a tell-tail sign that Earth was covered in a basic form of life.

By modeling different distributions of this microbe throughout the planet — in the oceans, on the land, around coastlines and during different atmospheric conditions — Sanroma’s team used a radiative transfer model “to simulate the visible and near-(infrared) radiation reflected by our planet.” By doing so, they were able to determine that by using multi-color photometric observations, distant observers would be able to “distinguish between an Archean Earth in which purple bacteria inhabit vast extensions of the planet, and a present-day Earth with continents covered by deserts, vegetation or microbial mats.”

When looking for Earth-like worlds, the researchers emphasize the need for exoplanet hunters to be aware that they may not discover a modern-looking Earth-like world, they may stumble across a purple bacteria-dominated world with a very distinctive photometric signature more fitting with an ancient Archean eon Earth-like world.

“Earth is the only planet where life is known to exist; thus observations of our planet will be a key instrument for characterization and the search for life elsewhere. However, even if we discovered a second Earth, it is very unlikely that it would present a stage of evolution similar to the present-day Earth.”

 This isn’t the first time that purple alien worlds have been discussed as a possibility. In 2011, researchers examined the exotic energy-generating regimes hypothetical alien plant life would need to develop under sunlight from binary stars.

Read more at Discovery News

Nov 13, 2013

Strange Object Boosts Kuiper Belt Mystery

There’s something odd floating around in the outer solar system. Actually, there’s lots of odd things floating around in the outer solar system, but 2002 UX25 is one of the most baffling.

The mid-sized Kuiper belt object (KBO) measures 650 kilometers (400 miles) across, and yet it has a density less than water (less than 1 gram per cubic centimeter). Yes, if you put it in a huge bathtub, 2002 UX25 would float.

As we probably all know by now, the Kuiper belt — a populated region of the solar system found just beyond the orbit of Neptune — is a strange place. Once thought to have a population of just one, astronomers have identified thousands of other minor planetary bodies. In fact, it was the accelerated discoveries in the Kuiper belt that ultimately led to the reclassification (or demotion, depending on which way you look at it) of Pluto from “planet” to lowly “dwarf planet.”

Now, in a paper accepted for publication in the The Astrophysical Journal Letters, planetary scientist Mike Brown, of the California Institute of Technology (Caltech) in Pasadena, has taken a measure of 2002 UX25′s density and discovered that it is “the largest solid known object in the solar system with a measured density below that of pure water ice.” Measuring the density of these distant objects are very difficult and require a small moonlet in orbit around the KBO so its orbital characteristics can be accurately measured and KBO density probed. The KBOs satellite was discovered by Hubble in 2005 and follow-up observations by the Keck Observatory in Hawaii refined its orbit.

This finding adds an extra twist to a strange dichotomy of KBOs. Objects with diameters less than 350 kilometers (218 miles) generally have densities less than that of water; objects over 800 kilometers (500 miles) have densities greater than water. One point in the gray area — between the diameter range of 350-800 kilometers — has just been added by 2002 UX25. But it is very large to have a density 18 percent less than water ice, a fact that surprised the veteran KBO hunter.

“The inferred low rock fraction of the 2002 UX25 system makes the formation of rock rich larger objects difficult to explain in any standard coagulation scenario,” Brown writes.

It is thought that KBOs formed in a similar way to asteroids and planets. Over the evolution of our solar system, small bits of rocky and icy debris coalesced, eventually forming planetesimals that then gathered more and more debris as their gravitational oomph grew. In this scenario, one would expect the density of minor planetary bodies to increase with increasing mass; the gravitational pressure of progressively larger bodies would cause more compression, thus increasing the density.

However, the very low densities of smaller KBOs are hard to explain without assuming that the bodies have a high degree of porosity. Porosity is a known factor in the formation of asteroids throughout the solar system — gaps throughout the structure of rocky bodies less than 350 kilometers in diameter are thought to lower the overall density. Asteroids over 350 kilometers become so massive that porosity decreases; the gravitational compression pulls the material closer together, reducing porosity and increasing density.

According to Brown, this porosity transition should occur in KBOs larger than 350 kilometers wide. But as 2002 UX25 shows, this transition hasn’t happened up to a size of 650 kilometers. This factor creates a problem. If larger KBOs over 1,000 kilometers (620 miles) formed through the coalescence of smaller KBOs (like 2002 UX25), it isn’t possible that large rock-rich KBOs could have such high densities.

In the case of an object the size of Eris, for example, with a measured density of 2.5 g/cm3, even with the gravitational compression exerted by the 2,326 kilometer-wide dwarf planet, the low density, high porosity material from an objects like 2002 UX25 cannot be compressed to such a high degree. Such an object “would still have a density close to 1 g/cm3 rather than the 2.5 g/cm3 density of Eris,” writes Brown. On this evidence alone, large KBOs cannot form through agglomeration of many small KBOs like 2002 UX25.

So what’s going on in the Kuiper belt? Brown offers a few explanations.

Perhaps there is some observational bias in the measurements of KBO density, or perhaps 2002 UX25′s density is not representative of mid-sized KBOs — it could be the ‘black sheep’ of the Kuiper flock. Could it be that the highest density, large KBOs formed through conventional agglomeration processes, only to have their densities beefed-up by energetic collisions early in the solar system’s history? Dwarf planet Haumea shows evidence for a massive collision in its past, which smashed the majority of its icy mantle away, leaving a rocky core behind — this had the effect of increasing the overall density of the object.

“None of these alternatives appears likely,” concludes Brown. “We are left in the uncomfortable state of having no satisfying mechanism to explain the formation of the icy dwarf planets. While objects up to the size of 2002 UX25 can easily be formed through standard coagulation scenarios, the rock rich larger bodies may require a formation mechanism separate from the rest of the Kuiper belt.”

Read more at Discovery News

Monkey-Human Ancestors Got Music 30 Million Years Ago

Music skills evolved at least 30 million years ago in the common ancestor of humans and monkeys, according to a new study that could help explain why chimpanzees drum on tree roots and monkey calls sound like singing.

The study, published in the latest issue of Biology Letters, also suggests an answer to this chicken-and-egg question: Which came first, language or music? The answer appears to be music.

"Musical behaviors would constitute a first step towards phonological patterning, and therefore language," lead author Andrea Ravignani told Discovery News.

For the study, Ravignani, a doctoral candidate at the University of Vienna's Department of Cognitive Biology, and his colleagues focused on an ability known as "dependency detection." This has to do with recognizing relationships between syllables, words and musical notes. For example, once we hear a certain pattern like Do-Re-Mi, we listen for it again. Hearing something like Do-Re-Fa sounds wrong because it violates the expected pattern.

Normally monkeys don't respond the same way, but this research grabbed their attention since it used sounds within their frequency ranges.

In the study, squirrel monkeys sat in a sound booth and listened to a set of three novel patterns. (The researchers fed the monkeys insects between playbacks, so the monkeys quickly got to like this activity.) Whenever a pattern changed, similar to our hearing Do-Re-Fa, the monkeys stared longer, as if to say, "Huh?"

"This kind of experiment is usually done by presenting monkeys with human speech," co-author Ruth Sonnweber said. "Designing species-specific music-like stimuli may have helped the squirrel monkeys' perception."

The squirrel monkeys demonstrated that they understood sound patterns -- and when they changed. This ability, central to language and music, therefore evolved at least 30 million years ago in the small and furry tree-dwelling primate that was the last common ancestor of humans and monkeys. It's likely that all primates today share the skills.

The non-human primate world might be more musical than we tend to think. Squirrel monkey calls are so high pitched and musical sounding that, to an untrained ear, they sound like bird songs. Chimpanzees drum on tree roots in the wild.

"My colleagues and I built some primate drum devices, basically tough musical instruments specifically designed for chimpanzees: they are electronic, so can produce virtually any sound when played," Ravignani said.

He added, "We already pilot-tested these electronic drums in a group of chimpanzees, and the animals' enthusiasm in using them to produce sounds spurred us to continue on this line of research."

Ravignani said they plan to collect sounds from chimpanzees and look for musical structures within.

Charles Snowdon, a professor of psychology and zoology at the University of Wisconsin-Madison, said the monkey study findings make sense.

"I think that the ability to produce and understand organized sound has been a trait of primates for a long time and, by this definition, many song birds can also be included, meaning that aspects of the origins of music can extend quite far back in evolution," Snowdon said.

Read more at Discovery News

Rare Life Dating Back 3.5 Billion Years Found

Gloppy mats of microscopic life left the same signature on coastal and river bank sediments 3.48 billion years ago that they do today. Earth scientists recently discovered that signature, known as a “microbially induced sedimentary structure” (MISS), on rocks from 300 million years earlier than any previously known MISS fossils.

A rock surface displaying “polygonal oscillation cracks” in the 3.48 billion years old Dresser Formation, Pilbara region, Western Australia.
To this day, MISS still forms in pools of stagnant water along rivers and lakes or in the muck of coastal mud flats. Complex communities of microorganisms form layers of slimy life in the moist environment. Over time the microbial mat etches its biological graffiti into rock after being buried by sediments and eventually turned to stone. MISS consists of visible polygonal cracks and gas domes in the rock, along with tell-tale microscopic features.

“The structures give a very clear signal on what the ancient conditions were, and what the bacteria composing the biofilms were able to do,” said Nora Noffke of Old Dominion University, lead author of the paper published in Astrobiology, in a press release.

Noffke and her colleagues mapped the fossilized microbial community down to the millimeter scale in rocks from the Pilbara district of western Australia. That district already claimed paleontological fame for the window on ancient life provided by fossilized stromatolites from there. Stromatolites look like large rocky mushrooms or cow poop plops. For the past 3.5 billion years, microscopic life has constructed the stony lumps by trapping sediments.

Read mroe at Discovery News

Oldest Big Cat Fossils Discovered in Tibet

The earliest known big cat lived in what is now China between 5.9 million and 4.1 million years ago, newfound fossils of the ancient prowler suggest.

The fossils, which were discovered on the Tibetan plateau, belong to a sister species of the snow leopard that prowls the Himalayan region today, said study co-author Zhijie Jack Tseng, a paleontologist at the American Museum of Natural History in New York.

The new study also reveals that all cats diverged about 16 million years ago, about 5 million years earlier than was previously thought.

The group of felines known as "big cats" includes tigers, leopards, lions and jaguars, as well as snow leopards and clouded leopards. But exactly where and when they evolved hasn't been clear.

Tseng and his colleagues were excavating a rocky region of badlands in the Tibetan plateau in 2010 when they uncovered a fossil skull and one other bone that seemed to belong to a big cat. On return trips, they excavated five more specimens of the cat. [See Images of the Big Cat Fossils]

The team didn't know how old the fossils were, so the researchers looked at the orientation of magnetic minerals in the rock layers around the fossils. Because the Earth's magnetic poles have flipped at known points in geologic time, counting the number of times magnetic particles switch orientation in nearby rocks can reveal the approximate age of a fossil.

The team concluded the big cat was at least 4 million years old — a few million years older than some other ancient tiger fossils.

A detailed look at the anatomy in comparison with other living and extinct cats revealed the primeval cat didn't look too different from a modern snow leopard.

But this cat is by no means the first feline from which all other cats evolved. After combining an analysis of the fossil cat's physical features with genetic data — including some from a fossil cave lion — the team puts the origin of all cats (including housecats) somewhere around 16 million years ago.

"These fossils are the oldest, but they're by no means the most primitive," Tseng told LiveScience. "There is some big cat out there that has yet to be described."

The findings are exciting because they corroborate genetic estimates of when cats first emerged, and because the fossils were found near Central Asia, the area where most scientists believe cats first evolved, said Julie Meachen, a paleontologist at Des Moines University in Iowa, who was not involved in the study.

In addition, the cat skull came from a region where other fossils of mega-creatures have been found, suggesting perhaps this is the region where Pleistocene megafauna, including "big furry guys" such as wooly mammoths and rhinos, evolved, Meachen said. (Megafauna are large or giant animals.)

It's also fascinating how little cats have changed over the past several million years, she said.

Read more at Discovery News

Nov 12, 2013

Was Jesus' Brother's Burial Box Vandalized?

A limestone box said to have once held the bones of the brother of Jesus was at the center of the most controversial forgery case in decades -- and it was allegedly vandalized by the Israeli government before being returned to its owner.

Called the James ossuary, it is a small stone box with an inscription that reads, "James, son of Joseph, brother of Jesus."

That Jesus had a sibling at all is a controversial idea disputed by the Roman Catholic Church. If the box itself were authentic, it would be considered the first physical link to Jesus.

A three-judge panel of Israeli Supreme Court justices ordered the Israel Antiquities Authority (IAA) to return the box and several other artifacts to antiquities collector Oded Golan last month, after the agency spent 10 years accusing Golan of forging the items.

The box will soon go on display for the public to view for the first time since 2002. There's just one problem: Reddish stains now appear over the inscription, remnants of a silicon substance applied by the Israel Police Forensics Laboratory to help determine the authenticity of the James ossuary.

The contamination might make it impossible to ever fully determine if this ancient relic is forged or real.

"The Israeli police, with permission of the IAA, made a red silicon mold of the inscription -- destroying the 'letter patina' by pulling out this 'soft' patina ... thus destroying evidence," said the geologists who first studied the ossuary in 2002, according to Jerusalem-based journalist Matthew Kalman who has covered Golan's trial extensively. "Consequently, the alleged small amount of masking letter patina is absent now and cannot be studied further."

A patina is a tarnish that forms on objects after a long period of time. It is one factor archaeologists use to determine the authenticity of artifacts.

Judge Aharon Farkash who presided over the case agreed that the process of making the mold left damage to the box and left him with reasonable doubt regarding Golan's guilty charge, Kalman reported.

"There is no dispute that the casting of the silicon by the forensics people changed the physical condition of the inscription of the ossuary," Judge Farkash said.

There is also confusion over the decision to create a silicon mold. The police officer who led the investigation testified that he asked the forensics lab to only "examine" the ossuary and not to carry out invasive tests, according to Kalman's report.

An IAA member who was part of the team of experts that ruled the ossuary a fake testified for the defense in regards to the contamination.

"I saw a picture of what happened to the ossuary," Orna Cohen told the court, calling it "contaminated," according to Kalman. "It will be hard to say anything about the ossuary itself."

Read more at Discovery News

King Tut Death by Chariot? Not So Fast

King Tutankhamun’s death is a mystery which may never be solved, says a new study on the best-known pharaoh of ancient Egypt.

The study indirectly dismisses a recent theory which ascribed King Tut's demise to a horrific chariot accident. According to the claim, which was detailed on Sunday in a new British documentary, the high-speed chariot crash would have smashed the boy king's rib cage and many of his internal organs, including his heart.

"It is not the first time that this mode of death has been mentioned," Salima Ikram, professor of Egyptology at The American University in Cairo, told Discovery News.

"I wonder how could they say his internal organs were crushed. We won't know until the canopic jars housing his organs are examined," she said.

Frank Rühli, Head of the Centre for Evolutionary Medicine at the University of Zurich in Switzerland, agreed.

"Moreover, the mechanism of explanation for the accident is not fully provable," Rühli told Discovery News.

According to the researchers, the diagnosis of trauma caused by a chariot accident is one of the many hypothesis about King Tut's death for which not enough evidence can be found.

To prove their point, Ikram and Rühli reviewed medical claims about the best-known pharaoh of ancient Egypt, starting from as far back as 1925, when the mummy was unwrapped in the outer corridor of the tomb of Seti II (KV15) by Howard Carter and others.

On that occasion, the mummy suffered some serious damage: it was dramatically disarticulated in the attempt to remove jewels and amulets.

Published in the latest issue of the Journal of Comparative Human Biology HOMO, the study is most comprehensive scientific assessment of the medical diagnoses on King Tut so far.

"The most important finding of this latest publication is that Tutankhamun's medical case remains unsolved despite almost 80 years of research," Rühli said.

Since its discovery and until the 21st century, King Tut's mummy has been officially examined only twice. In 1968 UK anatomist Ronald Harrison took the first X-rays. Ten years later James Harris, a dentist from Michigan, examined the body inside the burial as he took high-quality radiographs of the teeth.

In 2005, the mummy underwent non invasive CT scans. A team of international scientists, which included Rühli, reviewed over 17,000 images of the mummy, while ancient DNA analysis was carried out in the following years.

"It was the first-ever published CT of any positively identified ancient royal mummy, as well as the first published DNA study. Yet some results, especially on the molecular part, have been questioned by others," Rühli said.

According to the researchers, Tut's case shows the complexities of palaeopathology: a single individual, who has been studied in detail by so many groups, can yield so many and sometimes contradictory results of analyses -- not to mention speculations often resting in the realm of fantasy.

"Tutankhamun is a key figure in the history of ancient Egypt: his luxurious burial was found virtually intact and his untimely death has captured the imagination of scholars and enthusiasts alike," Ikram said.

"As neither his body nor historical texts provide a definitive explanation for his demise, a lot of conjectures based on slim evidence have come forth," she added.

Indeed, since the initial examination of the mummy by Carter and others, dozens of medical claims have been proposed. Diagnoses ranged from autologous or infectious diseases, metabolic disorders, tumorous conditions, trauma and even murder.

Overall, King Tut was diagnosed with a series of pathologies which included celiac disease, clubfoot, pigeon chest, Klippel-Feil syndrome, adrenal tumor, gynecomastia, endocrine abnormalities, Marfan's syndrome, tuberculosis, epilepsy, infestation by bilharzia and meningioma.

Claims of traumatic injuries have included a blow to the head by murderers, chest and face injuries caused by another chariot accident, a wound to the left ear due to an injury or even an insect bite -- resulting in a cerebral hemorrhage, and a kick in the chest by a horse or a hunting accident with a hippopotamus.

The CT-based analyses from 2005-2009 were able to rule out the majority of the pathologies proposed for the boy king.

Analysis of the body revealed a femur fracture, which may have caused the premature death of the king. Hawass and colleagues, who authored the study, suggested that the king's leg had been broken through an accident of some sort and that the pharaoh's death might have been due to septicemia and other complications to the wound.

"To me femur fracture is still likely. However, it is not fully proven, especially since in the 1920s a lot of damage has been set to the mummy," Rühli told Discovery News.

Read more at Discovery News

How Early Earth Cooled After Moon-Forming Impact

Billions of years ago, the Earth's atmosphere was opaque and the planet's surface was a vast magma ocean devoid of life.

This scenario, says Stanford University professor of geophysics Norman Sleep, was what the early Earth looked like just after a cataclysmic impact by a planet-size object that smashed into the infant Earth 4.5 billion years ago and formed the moon. The moon, once fully formed, which would have appeared much larger in the sky at the time, since it was closer to Earth.

Hundreds of millions of years later, he added, the first forms of life appeared, possibly having hitched a ride on a rock from Mars. The scenario is one presented by Sleep at a recent Royal Society conference here called Origin of the Moon. A paper detailing Sleep’s study was submitted to the symposium volume.

Although many elements of the theory have been around for some time, Sleep's synthesis is "like putting together a jigsaw puzzle with some pieces already known and some that are speculative and have new aspects," said Dave Stevenson, a Caltech professor of planetary science who was not involved with Sleep's study.

One of these new aspects is how Earth cooled down to the temperatures necessary for life to evolve, following the — presumed — giant impact that formed the moon.

The processes Sleep discussed took place in the period called Hadean, about 4 billion to 4.5 billion years ago — before the first organisms came into being, and well before more complex life-forms, including dinosaurs, started roaming the Earth.

Back then, the Earth was nothing like the blue Earth we know today.

Scorching world


Instead, the entire Earth was hot and molten all the way to its inner core, a mixture of molten rock and liquid.

No life would have been able to survive these brutally high temperatures, which reached 2,000degrees Celsius (more than 3,600 degrees Fahrenheit). Liquid water had no chance to form.

The Earth's atmosphere at this time was also much heavier. Its mass was similar to that of today's oceans, and it pushed down on Earth's surface with a pressure of hundreds of bars. (For comparison, the average pressure at the Earth's surface today is 1 bar). It was also opaque — "you would not have been able to see much, just clouds covering everything," Stevenson said.

Beneath the clouds, a magma ocean swayed, with partially molten rock pushed around by tides, Sleep hypothesizes.

These tides were due to the mutual attraction of the Earth and the moon, and were much stronger than those in today’s watery oceans, as the moon was sitting much, much closer to the Earth back then.

The tides constantly stirred the ocean, causing the mantle to lose heat, similar to stirring and blowing on a bowl of soup. But once released from the Earth's depths, the heat was trapped at the surface, held back by the thick, opaque primordial atmosphere.

The heat could only escape the planet (and cool it down) at so-called cloud-top temperature levels — where it would be as cold as on a modern high mountain summit. But for the first 10 million years, the temperatures were much, much higher, Sleep said.

The energy loss caused by the mutual attraction of the Earth and the moon was also making the moon gradually pull away. This made the tides progressively weaker, so the molten rock was being stirred less and less, and the Earth's mantle began to solidify in stages.

"While at the top of the Earth there was still partially molten slurry with a bit of liquid left, in the middle there was a mushy layer, but the deep mantle was becoming solid,” Sleep said. "Lava was probably still coming up and erupting and freezing at the top, and then falling back in large, kilometer-size pieces that were sinking into the Earth."

Slowly, the internal heat flow ceased to dominate the climate, and the temperatures at the surface began to drop, with the heat being able to escape the atmosphere at last.

Life from Mars?

The sweltering temperatures and trapped heat were not the only obstacles for life to appear, Sleep said.

Another issue was overabundance of carbon dioxide in the primordial atmosphere. Carbon dioxide doesn't dissolve in molten rock, so it was bound to bubble up from the magma ocean, creating a so-called runaway greenhouse effect, Sleep said.

For the Earth to become habitable, most of this carbon dioxide had to vanish.

Sleep said this happened when the tectonic plates began to move in the late Hadean, some 4.4 billion years ago. With the plates moving, the carbon dioxide began to enter the mantle in a process called subduction, when one tectonic plate moves under another and sinks into the mantle.

Liquid water oceans had already begun to condense around that time, and once the Earth cooled sufficiently and most of the carbon dioxide was safely tucked away in the mantle, life did finally appear, Sleep said, adding that chances are that this life arrived on Earth from Mars.

Read more at Discovery News

Evolution Is Steered by Competing Females

One of the classic images from evolutionary theory is of two males smashing each other up to compete for the chance to fertilize a female. Scientists have spent over a century studying this kind of male competition, but new discoveries reveal that competition between females is just as important.

The problem is that female competition and aggression don't always look like the male versions. As Paula Stockley and Anne Campbell argue in a special issue of The Philosophical Transactions of the Royal Society B, male competition is showy -- we can see fantastically armored beetles, the colorful tail of the peacock, and the often deadly fights between many male mammals.

But what we can't see are the ways that female mouse hormones spike at certain times of the year, causing them to become intensely aggressive toward other females. And until a great deal of observation had been done, scientists also hadn't seen the way female apes murder each other's babies.

Today, we have decades of data showing how competition between females, including human women, affects sexual selection and the evolution of a species. Stockley and Campbell introduce the new science of female competition with a selection of essays in the Royal Society B that pull back the curtain on the often hidden drama of female aggression.

Low-Cost Competition
One of the big themes in these studies is the fact that females invest so much energy in reproduction and child-rearing that they are unlikely to expend enormous amounts of energy on competition. Instead of smashing each other, they engage in low-cost forms of competition, often resolving the question of who gets to breed and who doesn't without ever fighting.

This isn't to say that there aren't many species where females do fight -- the spotted hyena is a good example. But on the whole, females tend to preserve their energy for reproduction. And there are a couple of interesting ways they do it.

First of all, keep in mind that these conflicts are motivated by the same things that motivate male conflicts in sexual selection. Females want access to mating partners, and to resources for their offspring. But how can one female prevent other females from mating without killing them? In many cases, they do it by teaming up.

Animals from insects to mammals cooperatively raise their young. High-status females have more children than low-status females, who are often their sisters. It is simply a better use of energy for the low-status females to accept their positions within the group and have fewer children.

You can even see this pattern among some groups of humans, such as the Mosou of southwestern China, where many generations of sisters live together and their husbands live elsewhere -- only visiting their wives at night. The older sisters tend to have more children, and do more farm work, then the younger ones. As Stockley and Campbell put it, "reproductive conflict among females more readily resolved to restraint among subordinates rather than escalated physical contests with their dominant."

Aggression Without Violence


Females tend to threaten each other with social isolation rather than violence. Among social animals, being cast out of the group can mean death, or very few chances to mate. Among humans, perhaps the most social animals we know, the "mean girls" phenomenon is a perfect example of low-energy competition. Nobody is beaten, but we know for sure who has lost the battle.

The problem with talking about humans, of course, is that we are not wild animals. As Stockley and Campbell are careful to point out, humans have been so influenced by culture that it's very hard to tell if a lack of overt aggression among women is an evolutionary or cultural artifact. Because so many women are culturally trained to tamp down their aggressive urges, it's impossible to call their behavior "natural."

So it's difficult to draw many conclusions about how early human women might have behaved 50,000 years ago based on how they behave today.

Flexible Behavior

To return to the world of animals, it's interesting to note that females seem to be aggressive in a much more flexible way than males. As I mentioned earlier, female mice go through periodic spikes in aggressive behavior, partly as a result of hormonal shifts.

Females also become more aggressive when they are defending their young. That's likely because the hormone oxytocin, released during and after pregnancy, isn't just a "love hormone" to spur mother/child bonding. It also governs aggression. So in the wake of pregnancy, when oxytocin levels are high, females are simultaneously more nurturing and more likely to go ninja on your ass.

Read more at Discovery News

Nov 11, 2013

Green Poison-Dart Frog Varies Mating Call to Suit Situation

In the eyes of a female poison-dart frog, a red male isn't much brighter than a green one. This does not however mean that the mating behavior of the green and red variants of the same species of frog is exactly the same. A study in Springer's journal Behavioral Ecology and Sociobiology, led by Beatriz Willink of the Universidad de Costa Rica in Costa Rica, sheds light on these findings.

The bright colors of poison-dart frogs serve not only to attract potential mates, but also to warn possible predators such as birds that these amphibians are poisonous. Different color variants within the same species occur, such as in the granular poison frog (Oophaga granulifera) of the southwestern lowlands of Costa Rica, where yellow and green color morphs have evolved from red ancestors.

Willink and her colleagues wanted to test if the green variants of the granular poison frog were more or less conspicuous to potential mates and predators than red ones of the same species. Therefore, they measured how the skin of the frogs contrasted with their natural background. This was done because dorsal brightness is known to influence female preferences in at least one poison frog species. The calling activity of 12 red and 10 green male frogs was also noted to determine if green males adjust their display behavior according to the availability of potential mates.

The results show that the green frogs, despite being less visible in some cases, may appear as bright as red frogs to members of their own species -- but not to birds -- when they are viewed on dark backgrounds.

Green frogs therefore seem to adjust their sexual behavior accordingly: They can deliver relatively conspicuous signals to females while being less conspicuous to potential predators. The researchers found that green males called less frequently than red males when advertising to distant females. However, their calling activity dramatically increased when a female was near and they became as vocal as red males. In the right context, when mating opportunity is certain, green males appear to trade-off the risk of predation for the mate-securing benefits of bold behavior.

Read more at Science Daily

The Experiments Most Likely to Shake Up the Future of Physics

The current era of particle physics is over. When scientists at CERN announced last July that they had found the Higgs boson – which is responsible for giving all other particles their mass – they uncovered the final missing piece in the framework that accounts for the interactions of all known particles and forces, a theory known as the Standard Model.

And that's a good thing, right? Maybe not.

The prized Higgs particle, physicists assumed, would help steer them toward better theories, ones that fix the problems known to plague the Standard Model. Instead, it has thrown the field into a confusing situation.

“We’re sitting on a puzzle that is difficult to explain,” said particle physicist Maria Spiropulu of Caltech, who works on one of the LHC's main Higgs-finding experiments, CMS.

It may sound strange, but physicists were hoping, maybe even expecting, that the Higgs would not turn out to be like they predicted it would be. At the very least, scientists hoped the properties of the Higgs would be different enough from those predicted under the Standard Model that they could show researchers how to build new models. But the Higgs' mass proved stubbornly normal, almost exactly in the place the Standard Model said it would be.

To make matters worse, scientists had hoped to find evidence for other strange particles. These could have pointed in the direction of theories beyond the Standard Model, such as the current favorite supersymmetry, which posits the existence of a heavy doppelganger to all the known subatomic bits like electrons, quarks, and photons.

Instead, they were disappointed by being right. So how do we get out of this mess? More data!

Read more at Wired Science

U.S. to Destroy 6 Tons of Ivory This Week

In a first, U.S. officials are going to destroy their massive stockpile of illegal ivory this week, hoping to send a zero-tolerance message to elephant poachers.

On Thursday (Nov. 14), the U.S. Fish and Wildlife Service (FWS) will pulverize nearly 6 tons (5.4 tonnes) of illegal ivory items, from whole tusks to tiny trinkets, which have been seized over the past 25 years as a result of smuggling busts and criminal investigations.

The ivory crush will take place at the Rocky Mountain Arsenal National Wildlife Refuge in Commerce City, Colo., just outside of Denver.

Seized ivory is typically kept as evidence until criminal cases are over. After that, the objects can be used to educate the public and train law enforcement officials. But FWS officials say that since the 1980s they have collected far more ivory than they need to fulfill those purposes. Thursday's event will mark the first time such a large amount of ivory is being destroyed in the United States.

"Destroying this ivory tells criminals who engage in poaching and trafficking that the United States will take all available measures to disrupt and prosecute those who prey on and profit from the deaths of these magnificent animals," FWS officials said in a fact sheet.

The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) banned the international ivory trade in 1989. But a CITES report published last year found that elephant poaching was at its highest level in a decade and rising.

Read more at Discovery News

Snakes Control Blood Flow to Boost Vision

Snakes have infamously poor eyesight, which is why they resort to sticking out their tongues all the time to get a sense of their surroundings. But the creatures may have a way to improve their vision in a pinch.

At least for one snake species, when the slitherer feels threatened, it controls the blood flow to its eyes to ensure that its sight is unobstructed, a new study found.

The research focused on the coachwhip snake (Masticophis flagellum), a thin, nonvenomous species that is found across the United States and Mexico and can range in color from brown to pink.

Like all other snakes and many other reptiles, coachwhip snakes don't have eyelids but rather a transparent scale called a spectacle that covers and protects the eye.

While examining the eye of a coachwhip snake, study researcher Kevin van Doorn, of the University of Waterloo in Canada, said he noticed a network of blood vessels in this see-through layer of skin.

Van Doran further investigated this feature. He found that the blood vessels constricted and expanded in a consistent cycle while the snakes were resting so that blood cells wouldn't pool up in front of the animals' eyes and obscure their already limited vision.

But faced with a threat (in this case, a human approaching their terrarium), the snakes abandoned this rhythm. They constricted these vessels, reducing blood flow for up to several minutes and ensuring topnotch visual clarity in case they needed to defend themselves or flee from a predator, the researchers said. The opposite was true as the snakes were shedding their skin; the spectacle vessels remained dilated, keeping the blood flow continuous, which probably supports cell growth as the snake renews the outer layer of its skin, according to the study.

Read more at Discovery News

Nov 10, 2013

Universals of Conversation: Words Like 'Huh?'

A word like 'Huh?' -- used when one has not caught what someone just said -- appears to be universal: it is found to have very similar form and function in languages across the globe. This is one of the findings of a major cross-linguistic study by researchers Mark Dingemanse, Francisco Torreira and Nick Enfield, at the Max Planck Institute for Psycholinguistics in Nijmegen, the Netherlands. The study was published in the journal PLOS ONE.

It might seem frivolous to carry out scientific research on a word like 'Huh?' But in fact this little word is an indispensable tool in human communication. Without words like this we would be unable to signal when we have problems with hearing or understanding what was said, and our conversations would be constantly derailed by communicative mishaps. The research is part of a larger investigation of language and social interaction funded by the European Research Council.

Dingemanse and colleagues studied languages from around the world and found that all of them have a word with a near-identical sound and function as English 'Huh?' This is remarkable because usually, words in unrelated languages sound completely different. Compare, for example, these very different-sounding words for 'dog': inu in Japanese, chien in French, dog in English. One might object that this suggests that 'Huh?' is not a word at all. But in a careful phonetic comparison, Dingemanse and colleagues find that it is. Although 'Huh?' is much more similar across languages than words normally should be, it does differ across languages in systematic ways. 'Huh?' is not like those human sounds that happen to be universal because they are innate, such as sneezing or crying. It is a word that has to be learned in subtly different forms in each language.

Why is 'Huh?' so similar across languages? To understand this, Dingemanse and colleagues studied the specific context in which this word occurs. In human communication, when we are somehow unable to respond appropriately, we need an escape hatch: a way to quickly signal the problem. This signal has to be easy to produce in situations when you're literally at a loss to say something; and it has to be a questioning word to make clear that the first speaker must now speak again. Since these functional requirements are fundamentally the same across languages, they may cause spoken languages to converge on the same solution: a simple, minimal, quick-to-produce questioning syllable like English 'Huh?', Mandarin Chinese 'A?', Spanish 'E?', Lao 'A?', or Dutch 'He?'.

The basic principle is well-known from evolutionary biology: when different species live in similar conditions they can independently evolve similar traits, a phenomenon known as convergent evolution. For example, sharks and dolphins have different evolutionary origins but similar body plans, because they live in the same aquatic environment. In the same way, Dingemanse and colleagues propose that words may converge on similar forms when they occur in strongly similar conversational 'environments'. A clear effect of this conversational ecology on the specific shape of linguistic expressions has not been observed before.

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Kidney Damage in First Responders Linked to 9/11

For the first time, researchers have linked high levels of inhaled particulate matter by first responders at Ground Zero to kidney damage. Researchers from the WTC-CHEST Program, a subset of the World Trade Center Health Program Clinical Center for Excellence at Icahn School of Medicine at Mount Sinai, presented their new findings at the 2013 American Society of Nephrology meeting on Nov. 9 during National Kidney Week.

After the 9/11 tragedy, first responders at Ground Zero were exposed to varying levels of a dust cloud of air filled with cement dust, smoke, glass fibers, and heavy metals. The WTC-CHEST Program at Mount Sinai has previously linked this particulate matter exposure to lung and heart abnormalities. However, its effects on the kidney health of first responders have never been explored until now.

In their new study, Mount Sinai researchers examined urine samples of 183 first responders exposed to particulate matter at Ground Zero taking into account each first responder's time of arrival, proximity, duration, and level of exposure at Ground Zero. To assess their kidney damage, researchers measured the level of the protein called albumin in their urine, which when this main blood protein is found in urine it is abnormal and an indicator of renal damage. Research results show a significant link between a high level of exposure to particulate matter by first responders at Ground Zero and the increased level of the protein albumin in their urine.

"Our study shows the first responders with the highest exposure to the 9/11 particulate matter had significantly greater levels of albumin in their urine than the first responders in the study with low exposure levels," says Mary Ann McLaughlin, MD, principal investigator for the WTC-CHEST Program at Icahn School of Medicine at Mount Sinai who also serves as medical director of the Cardiac Health Program and co-director of the Women's Cardiac Assessment and Risk Evaluation Program at The Mount Sinai Hospital. "We believe high exposure to the massive dust cloud of air pollution at Ground Zero may have extremely inflamed the endothelial lining of blood vessels leading to the kidneys causing kidney malfunction and the development of kidney damage in first responders."

Albumin may leak into the urine when kidney function is compromised from inflammation or kidney damage. When albumin starts to spill incorrectly into the urine it is called "albuminuria." A high-level of albuminuria can signal kidney disease from diabetes, high blood pressure, heart failure, and kidney inflammation. Standard medical assessments test for albuminuria to catch kidney disease early. When kidney disease progresses, it can lead to kidney failure, kidney dialysis, or even potentially a kidney transplant.

"We observed a statistically significant and independent relationship between first responder's high exposure to particulate matter and albuminuria," says Dr. McLaughlin. "Our novel research findings will pave the way for the future early diagnosis and care of these first responders' impaired kidney health. Also, in addition, it will lead to further exploration of the impact of environmental exposures and inflammation in the pathogenesis of albuminuria."

This research study was funded by the Centers for Disease Control and Prevention (CDC) and the National Institute of Occupational Safety and Health (NIOSH).

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