Mike Shapiro / University of Utah

Two rock pigeon breeds, the old Dutch capuchine (left) and komorner tumbler, are not closely related, yet they both have feathery ornamentation on their heads known as a crest.

By Jeanna Bryner
LiveScience

The rock pigeon's funky hairdos have been pinned to a single gene mutation that signals head and neck feathers to grow up rather than down in a tamer fashion, report researchers who have just decoded the bird's genome.

"A head crest is a series of feathers on the back of the head and neck that point up instead of down," study researcher Michael Shapiro said in a statement. "Some are small and pointed. Others look like a shell behind the head; some people think they look like mullets. They can be as extreme as an Elizabethan collar."

In addition to diverse "updos," the rock pigeon — a single species (Columba livia) — shows incredible variety in several other traits, including beak size, vocalizations, color patterns and bone structure, among its 350 different breeds.

"We're interested in pigeons, because they're this beautiful example of amazing diversity within a single species," Shapiro, an assistant professor of biology at the University of Utah, told LiveScience. [ Crazy Crests: Photos of Stunning Pigeon Hairdos ]

Pigeon genes
To look at the genetics behind the diversity, Shapiro and his colleagues focused on a male rock pigeon from the Danish tumbler breed, assembling more than a billion chemical bases that pair up to form "rungs" on the "DNA ladder." Discrete units of DNA make up an organism's genes.

Courtesy of Mike Shapiro

The rock pigeon is a single species (Columba livia) with 350 different breeds with different sizes, shapes, colors, color patterns, beaks, bone structure, vocalizations and arrangements of feathers on the feet and head — including head crests that come in shapes known as hoods, manes, shells and peaks.

They also sequenced the partial genomes of two feral pigeons (one from a U.S. Interstate 15 overpass in the Salt Lake Valley, and the other from Lake Anna in Virginia) and 38 other rock pigeons from 36 breeds.

The researchers lined up the genomes of birds with and without crests, finding a particular region in the genome that was highly differentiated between the two groups. Using a software tool the researchers found the so-called EphB2 gene could explain the difference; Shapiro and his colleagues say the gene acts like a switch for head crests, keeping feathers growing downward in its normal form and upward when mutated.

"We know this group of genes plays an important role in feather development," Shapiro told LiveScience, "though the role of this gene isn't completely understood yet."

He added that other genes likely control the variation in these head crests.

And while the fancy hairdos don't show themselves until pigeons are juveniles, the mutant gene is at work much earlier, reversing the direction of feather buds at the molecular level when the birds are just embryos.

Pigeon roots
The genetic results also revealed some of the pigeons' roots, showing the owl breeds (a group with short beaks) likely came from the Middle East, as they showed close ties with breeds known to have originated in Syria, Lebanon and Egypt, Shapiro said.

The findings also match historical accounts of trade routes: The team found a breed called fantails, which are typically associated with India, are related to breeds whose ancestors are known to have come from Iran.

"There are accounts from a time of Emperor Akbar in India that verify there were pigeons being exchanged between those two regions — India and Iran — or at least the Middle East," Shapiro said during a phone interview. "Akbar was apparently getting gifts of pigeons."

The study, which is detailed Thursday in the Science journal's website Science Express, involved collaboration between China's BGI-Shenzhen, the University of Utah, the University of Copenhagen and the University of Texas M.D. Anderson Cancer Center.

Shapiro also noted the study would not have been possible without various pigeon breeders. "The pigeon breeders have been absolutely essential in this research, in material and expertise. And we could not have done it without them."

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Courtesy of LiveScience

There are a couple of good reasons, researchers found, why some owls can rotate their heads 270 degrees in each direction.

By Douglas Main
Our Amazing Planet

Owls don't need eyes in the back of their heads to see what's behind them — they can just swivel their heads all the way around. In fact, many owl species, such as the barred owl, can rotate their heads 270 degrees in each direction, which means they can look to the left by rotating all the way to the right, or vice versa.

But how do they do it without severing their arteries or preventing blood from reaching the brain ? An illustrator and a physician at the Johns Hopkins University School of Medicine teamed up to find out.

"Until now, brain imaging specialists like me who deal with human injuries caused by trauma to arteries in the head and neck have always been puzzled as to why rapid, twisting head movements did not leave thousands of owls lying dead on the forest floor from stroke," said study author Dr. Philippe Gailloud, in a statement from the university.

If humans tried to rotate our heads so rapidly or far, we'd tear the lining of our arteries, which would cause clots to form and lead to a stroke (besides also breaking our necks), he added. "The carotid and vertebral arteries in the neck of most animals — including owls and humans — are very fragile and highly susceptible to even minor tears of the vessel lining."

Fabian de Kok-Mercado and Dr. Philippe Gailloud

Fabian de Kok-Mercado (left) and Dr. Philippe Gailloud give a CT scan to a dead owl to learn how its blood vessels withstand the rapid, up-to-270-degree turns their heads make.

Looking inside owls
To get a glimpse of the owl's blood vessels when their necks were turning, the duo injected dye into the blood vessels of a dozen dead owls and used a CT scan to visualize the shimmering fluid spreading throughout the birds' arteries like blood, said Fabian de Kok-Mercado, who performed the work while getting a master's in medical illustration at Johns Hopkins. (He is now an illustrator at the Howard Hughes Medical Institute in Chevy Chase, Md.) The researchers then twisted the dead owls' heads to see what happened. [ Video: Watch the owls' necks twist.]

After creating the CT scan images, the researchers injected a plasticlike substance into the veins of dead snowy, barred and great horned owls and dissected the animals, drawing the routes and locations of the vessels.

They found a number of previously undiscovered and unique traits, de Kok-Mercado told OurAmazingPlanet. For one, the owls' neck bones, or vertebrae, contain holes that are much larger than those found in other birds or humans. In humans, the hole in the vertebra is about the same size as the artery, but in owls the hole is about 10 times larger than the artery, according to the study, published Thursday in the journal Science. These holes, or canals, likely hold air sacks meant to cushion the twisting motion of the head, de Kok-Mercado said.

"We also noticed right away that these canals were absent in the bottom two vertebra of the neck," de Kok-Mercado said. This gives the cordlike vessels some slack when the bird twists its head.

The large holes and "slack" at the bottom of the neck help explain why the vessels don't break. But they don't explain why the supply of blood isn't cut off when an owl turns its head — with so much twisting, the vessels are bound to become partially blocked.

Blood to the brain
The team noticed that the vertebral artery enlarges slightly as it approaches the brain, which is unusual and not seen in many other animals (like the trunk of a tree, vessels generally get smaller as they get farther from the heart). The authors think that these enlarged areas may function as reservoirs in which blood can pool, so that the brain has extra blood to work with as the head swivels around, de Kok-Mercado said.

The blood vessels near the brain are also highly connected. A vessel called the patent trigeminal artery connects the front and the back of the owl's brain, which helps supply the organ with as much blood as possible.

Why do owls need to crane their necks to such an extreme degree? It's because their eyes are tubular, built almost like telescopes, giving them amazing vision, de Kok-Mercado said. But unlike humans, who have roughly spherical eyes, owls cannot move them about easily, so they have to rotate their heads.

The finding is just another example of how the birds are perfectly adapted to suit their environment, enabling them to see despite having relatively fixed eyes.

"I hope it gives people more of an appreciation of the life on this planet," de Kok-Mercado said.

Reach Douglas Main at dmain@techmedianetwork.com. Follow him on Twitter @Douglas_Main. Follow OurAmazingPlanet on Twitter @OAPlanet. We're also on Facebook and Google+.

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Cody Karutz

A virtual child after being found and saved in a "superhero study."

By Charles Q. Choi
LiveScience

It's a bird! It's a plane! It's a superhero flying in a virtual sky! Scientists now find that seeing superpowers in a virtual-reality game may lead people to act more virtuously in real life.

Virtual-reality technology uses video displays and other gear to immerse people in realistic digital environments. Virtual reality can lead to mind-bending experiences, such as making users think they have swapped bodies with someone else. The effects of virtual reality can endure long after these experiences, which psychologists hope can help in therapies for ailments such as phobias and post-traumatic stress disorder.

To see if embodying a helpful role in virtual reality made people more helpful afterward, scientists had 60 volunteers don virtual reality helmets and engage in scenarios where they were either given the power of flight or rode as passengers in a helicopter. They were also assigned one of two tasks — they had to tour a virtual city or help find a missing diabetic child in need of insulin.

Regardless of which task the volunteers performed, those who were given the power to fly like Superman in virtual reality were more helpful afterward in the real world compared with participants who were passengers in the virtual helicopter. Specifically, volunteers who had virtual superpowers moved about three times faster on average than virtual helicopter passengers did to help experimenters pick up spilled pens after their virtual experiences — in fact, the six volunteers who did not help at all had all ridden in the virtual helicopter. [ Hero Helpers: 10 Best Sidekicks in Comic Book History ]

Cody Karutz

In Panel A, the experimenter is "accidentally" knocking over the pens; in Panel B, a participant gets out the chair and kneels to help pick up the pens. Note: The images are slightly blurry as the surveillance cameras do not capture in high resolution.

"The experience of super-flight in and of itself appears to be the salient variable that led people to help outside of virtual reality," said researcher Robin Rosenberg, a clinical psychologist in private practice in Stanford, Calif., and author of "Superhero Origins: What Makes Superheroes Tick and Why We Care" (CreateSpace Independent Publishing Platform, 2013).

The investigators suggest that embodying a superpower in virtual reality may prepare players to think like superheroes so that they behave better later. Another possibility is that participants given the virtual superpower of flight may have felt more active than those who passively sat in the helicopter, and this mindset may have influenced their subsequent behavior.

The scientists said they shared their findings with Paul Levitz, a comic book editor and writer and former DC Comics publisher and president.

Levitz noted that people familiar with superhero tropes implicitly know that after characters discover superpowers, they have to decide to use them for personal gain or for the greater good. Perhaps that implicit knowledge influenced this study, leading super-flight volunteers to decide unconsciously and perhaps automatically to use their power for good.

This research could potentially be applied to creating games that could help promote real-life helpful behavior in both children and adults.

"As console gaming devices increasingly bring elements of virtual reality info people's homes, such experiences may have a significant effect on real-world behavior and the potential to do good," Rosenberg told LiveScience.

Future studies might investigate whether embodying a specific superhero such as Superman might strengthen this effect. Also, "do these results generalize to regular computer experiences — for example, computer games — or is virtual reality a key ingredient?" Rosenberg asked. "Would more time flying in virtual reality lead to a greater effect?" And "would giving people different enhanced abilities or powers, such as super strength, heat or laser vision, lead to the same effect?"

Rosenberg and colleagues Shawnee Baughman and Jeremy Bailenson detailed their findings online Wednesday in the journal PLOS ONE.

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Courtesy of LiveScience

Researchers developed a way to follow neural signals in the brain of a zebrafish larva, using a sensitive fluorescent marker.

By Tanya Lewis
LiveScience

For the first time, scientists have imaged the brain activity of a fish watching its prey.

Observing neural signals in real time offers an important glimpse into how brains perceive the outside world. In the new study, researchers developed a way to follow these signals in the brain of a zebrafish larva, using a sensitive fluorescent marker.

"It's a breakthrough," molecular and cell biologist Florian Engert of Harvard University, who was not involved in the study, told LiveScience. "No one else can look at neuronal activity with fluorescence microscopy in a freely swimming zebrafish larva" with such good resolution.

See-through heads
Zebrafish are widely used to study genetics and development in vertebrates. Their larvae are ideal for neuroimaging because they have translucent heads, and scientists can literally peer into their brains.

To see what was actually going on in those fish noggins, researchers developed a genetically engineered protein, called GCaMP7a, that lights up under a fluorescent microscope when neurons, or brain cells, fire. Transgenic zebrafish were bred to express this protein in a brain region called the optic tectum, which controls the movement of the eye when the animal sees something move in its environment.

In one experiment, the scientists imaged the brain of a transgenic fish larva as it watched a dot on a screen blinking on and off or moving back and forth. Under the microscope, signals flashed through the fish's brain, mirroring the movement of the dot. [See video of the fish's brain.]

Next, a live paramecium — zebrafish prey — was placed in sight of an immobilized fish. Again, neural signals could be seen zipping around the fish's brain, tracking the paramecium's movement. No signals were detected when the paramecium was motionless, however.

Lastly, a paramecium was placed in a dish with a zebrafish larva that was allowed to swim freely, hunting its prey. The researchers mapped the fish's brain activity as it zeroed in on the paramecium and swam toward it.

Understanding brain behavior
The new approach will improve scientists' understanding of brain circuits involved in predatory behavior, the researchers report online Thursday in the journal Current Biology. The system could be used to image other brain areas, too, allowing scientists to observe neurons involved in behavior and locomotion.

Previously, scientists had been able to image single-cell brain activity in zebrafish, but this study was the first to do it in a freely swimming fish perceiving a natural object. "The technology for studying zebrafish is moving fast," said neuroscientist Joseph Fetcho in an email to LiveScience. Fetcho did some of the earlier imaging work but was not involved in the new study.

The closer you can get to revealing the patterns of neuronal activity in a freely behaving animal, the more likely the patterns will represent those that drive natural behavior, Fetcho said.

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Courtesy of The Tasmanian National Museum and Gallery

Tasmanian tigers (Thylacinus cynocephalus) looked somewhat like striped coyotes and were found throughout most of the Australian island of Tasmania before Europeans settled there in 1803.

By Megan Gannon
LiveScience

Humans alone were responsible for the Tasmanian tiger's extinction in the 20th century, according to a new study that shoots down claims that disease also doomed the meat-eating marsupial.

More officially known as thylacines, Tasmanian tigers (Thylacinus cynocephalus) looked somewhat like striped coyotes and were found throughout most of the Australian island of Tasmania before Europeans settled there in 1803.

Starting at the end of the 19th century, the Tasmanian government paid bounties for thylacine carcasses, as the animals were believed to prey on farmers' sheep and poultry. (A recent study, however, showed that the carnivores' jaws were so weak they likely couldn't have taken down anything larger than a possum.) Humans eventually hunted thylacines to extinction in the early 1900s; the last known individual died in a Tasmanian zoo in 1936.

"Many people, however, believe that bounty hunting alone could not have driven the thylacine extinct and therefore claim that an unknown disease epidemic must have been responsible," researcher Thomas Prowse of Australia's University of Adelaide said in a statement.

Prowse and his colleagues developed a mathematical model to evaluate whether the combined impacts of Europeans' settlement could have wiped out the thylacine, without any disease involved.

"The new model simulated the direct effects of bounty hunting and habitat loss and, importantly, also considered the indirect effects of a reduction in the thylacine's prey (kangaroos and wallabies) due to human harvesting and competition from millions of introduced sheep," Prowse said.

Indeed, their results, published this month in the Journal of Animal Ecology, showed that these impacts alone would have been powerful enough to send the Tasmanian tiger population crashing in the early 20th century.

A study out last year suggested that low genetic diversity eventually would have set the thylacine on a path to extinction even if they hadn't been hunted off the planet.

The tiger's extant cousin, the Tasmanian devil, is currently being wiped out by a contagious cancer that's been able to spread all the easier because of the devil's low genetic diversity, which cuts down a wildlife population's ability to adapt to changing environmental conditions and bounce back from disease and mass fatalities. The Tasmanian tiger, if around today, also would be exceptionally susceptible to diseases, those researchers said.

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Yamamoto S, Humle T, Tanaka M (2013) Basis for Cumulative Cultural Evolution in Chimpanzees: Social Learning of a More

Like humans, chimpanzees display the ability to learn techniques by watching others.

By Tanya Lewis
LiveScience

Chimpanzees can learn to use tools more efficiently by watching how others use them, new research suggests. The findings help illuminate ways that culture could evolve in nonhuman animals.

"Social learning is very important to maintaining a culture," study researcher Shinya Yamamoto of Kyoto University in Japan told LiveScience. "For example, in humans, we can develop technologies based on previous techniques, and other people can learn the more efficient techniques by accumulating cultural knowledge." The new research provides insight into how cultural evolution might occur in chimpanzees.

In the study, nine captive chimpanzees at the Primate Research Institute at Kyoto University were presented with a straw-tube they could use to obtain juice from a bottle through a small hole. Of their own accord, the chimps used one of two techniques to get the juice: "dipping" and "straw-sucking." The dipping technique involved inserting the straw into the juice and removing it to suck on the end, whereas straw-sucking entailed sipping the juice through the straw. Straw-sucking was a much more efficient means of getting juice than dipping.

Five of the chimps initially used the dipping method and four used the straw-sucking method. The researchers then paired each of the five chimps who used dipping with a chimp who was a straw-sucker. Four of the dippers switched to straw-sucking after observing the other animal using the more effective technique. The fifth dipper switched too, but only after watching a human using it. [ See video of the chimps.]

Chimps who paid the most attention to the straw-sucking demonstrator switched to the new method more rapidly. After switching, the animals never reverted to the dipping method.

The apes' adoption of the straw-sucking technique shows social learning, the researchers say. The chimpanzees who were dippers "didn't learn the sucking technique by themselves, only when they are paired with the sucking individual," Yamamoto said. The one chimp that didn’t adopt the new technique right away may have been subordinate to her partner chimp, Yamamoto said. As soon as Yamamoto demonstrated the technique, however, the chimp started using it.

The results contrast with the findings of previous studies, which have shown that chimpanzees don't always adopt an improved technique used by others. One explanation may be that unlike in previous studies, the better technique (straw-sucking) was no more physically or mentally difficult to perform than the original technique (dipping), the researchers said. Additionally, the chimpanzees in previous studies seemed satisfied with using their original technique, whereas these chimps may not have been content with their method's efficiency, the researchers added.

This study and others like it "add to the idea that the apes are very well capable of social learning," primatologist Frans de Waal of Emory University in Atlanta told LiveScience.

Scientists have debated for decades about whether or not animals have culture. "We cannot hold chimpanzees against the standard of modern-day human culture," de Waal, who was not involved with the research, said, but "the border is much grayer than we thought."

The study was published online Wednesday in the journal PLOS ONE.

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Luiz Flavio Lopes

Fossilized shark poop, called a coprolite (shown here), was found to contain ancient tapeworm eggs.

By Charles Choi
LiveScience

Ancient tapeworm eggs found in 270-million-year-old shark poop suggest these parasites may have plagued animals for much longer than previously known, researchers say.

Tapeworms cling to the inner walls of the intestines of vertebrates — creatures with backbones such as fish, pigs, cows and humans. When these parasites reach adulthood, they unleash their eggs on the world via the feces of their hosts.

Investigating the early history of such parasites of vertebrates is tricky because fossils of these parasites dating back to the age of dinosaurs or before are rare. One way researchers might unearth such fossils is by analyzing coprolites, or fossilized dung.

Scientists now reveal they found a spiral-shaped coprolite from a shark that holds a cluster of 93 oval tapeworm eggs. One of them even contains a probable developing larva, which held a cluster of fiberlike objects that may have been the beginnings of hooklets used to attach to a host's intestines as adults. [ See Photos of the Parasite Eggs & Fossil Poop ]

The fossils, unearthed in southern Brazil, date to the Paleozoic era (251 million to 542 million years ago), before dinosaurs roamed the Earth. This predates other known examples of intestinal parasites in vertebrates by 140 million years.

Bruno Horn

Researchers found a cluster of 270-million-year-old tapeworm eggs (shown here) in fossilized shark poop.

The eggs are each only about 150 microns long, or about one-and-a-half times the average width of a human hair. The researchers discovered the eggs by cutting coprolites into thin slices.

"Luckily in one of them, we found the eggs," researcher Paula Dentzien-Dias, a paleontologist at the Federal University of the Rio Grande in Brazil, told LiveScience. "The eggs were found in only one thin section."

This coprolite was found with more than 500 others at one site. The researchers suggest the area was once a freshwater pond where many fish got trapped together during a dry spell.

The mineral pyrite, also known as fool's gold, was found in the coprolite. This suggests its environment was depleted of oxygen, conditions that probably helped preserve the fossils for millions of years.

There is no way of knowing for certain what specific type of shark left this fossil behind, since all sharks have similar intestines (and thus poop). It is unlikely the tapeworm infestation killed the shark that left this coprolite, unless the infestation was huge, Dentzien-Dias said.

The researchers are now examining similar coprolites at the same outcrop. "We have to choose between 500 coprolites which ones will be cut," Dentzien-Dias said.

The scientists detailed their findings online Wednesday in the journal http://dx.plos.org/10.1371/journal.pone.0055007">PLOS ONE.

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Anja Scheffers. Boka Bartol

A coastal lagoon on the Caribbean island of Bonaire.

By Charles Q. Choi
Our Amazing Planet

An ancient tsunami caused dramatic long-term ecological changes in the Caribbean more than 3,000 years ago, new research suggests.

Scientists investigated sediments from a coastal lagoon on the Caribbean island of Bonaire about 50 miles (80 kilometers) north of the Venezuelan coast. The Caribbean is highly vulnerable to coastal hazards such as hurricanes, tsunamis, mudslides and floods.

Bonaire has not experienced a tsunami during the past 500 years of its recorded history. However, analysis of the size of sediment grains found on the island, the organic matter present in the sediment (such as animal remains and carbonate minerals), as well as other factors suggest that a devastating wave struck the island about 3,000 to 3,300 years ago.

"We assume that the height of the ancient tsunami along the coast was at least 8 to 9 meters (26 to 30 feet) as inferred from the size of transported boulders," said researcher Max Engel, a coastal geomorphologist at the University of Cologne in Germany. [ 7 Ways the Earth Changes in the Blink of an Eye ]

Altered ecosystem
The researchers estimate the tsunami reached at least 820 feet (250 m) onshore. "Lagoons and valleys of the island might be inundated up to a kilometer (0.6 miles) or more, and the flat and low-lying southern tip of the island might have been entirely inundated," Engel told OurAmazingPlanet.

This catastrophe apparently altered the coastal ecosystem and sedimentation patterns in the area. In the wave's aftermath, a barrier of coral rubble separated a former mangrove-fringed bay from the open sea, transforming it into a highly salty lagoon that has persisted up to now.

"Large tsunamis may occur on the ABC islands — Aruba, Bonaire, Curaçao — even though tsunamis have never been observed in historical times," Engel said.

Uncertain source
It remains uncertain where this tsunami might have come from. "The most likely source would be a local to regional tsunami triggered by an earthquake along the southern boundary of the Caribbean tectonic plate — that is, the coast of Venezuela," Engel said. For instance, historical records suggest a devastating tsunami in 1530 was triggered by an earthquake near Cumaná, Venezuela.

In addition, a strong earthquake at the northeastern boundary of the Caribbean cannot be excluded as the tsunami's cause either. For instance, the 1867 temblor in the Anegada Passage in the U.S. Virgin Islands triggered a tsunami that traveled across the Caribbean. "Further possible trigger mechanisms include submarine volcanic activity in the southern Antilles island arc, though these tsunamis tend to be local," Engel said.

The wave may even have been a "teletsunami," an oceanwide tsunami originating on the other side of the Atlantic.

"For instance, computer models indicate that the collapse of a flank of the Cumbre Vieja volcano in the Canary Islands into the sea may induce a tsunami that still reaches a height of several meters after crossing the Atlantic Ocean and approaching the Caribbean islands and the southern coasts of North America," Engel said.

The investigators said further studies should look for evidence of tsunamis across the entire Caribbean to reconstruct reliable patterns of tsunami magnitude, frequency and location, as well as their environmental impact. In addition, researchers should develop computer models simulating earthquake-triggered tsunamis capable of creating the pattern of coastal flooding on Bonaire that matches the geological evidence to identify a possible trigger mechanism posing a threat in the future.

"We provided evidence for a potential hazard for which there is no real awareness on Bonaire," Engel said. "I hope this work contributes to an increase in public awareness on a local and regional level."

Engel and his colleagues detailed their findings in the January issue of the journal Naturwissenschaften.

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By Barbara Liston
Reuters

Americans may be turning away from the hard sciences at universities, but they are increasingly showing up at "science cafes" in local bars and restaurants to listen to scientific talks over a drink or a meal.

Want a beer with that biology? Or perhaps a burger with the works to complement the theory of everything?

Science cafes have sprouted in almost every state including a tapas restaurant near downtown Orlando where Sean Walsh, 27, a graphic designer, describes himself and his friends as some of the laymen in the crowd.

"We just want to learn and whatever we take in, we take in. But we're also socializing and having a nice time," said Walsh, who a drank beer, ate Tater Tots and learned a little about asteroids and radiation at two recent events.

Others in the crowd come with scientific credentials to hear particular scientists lecture on a narrowly focused field of interest.

But the typical participant brings at least some college-level education or at least a lively curiosity, said Edward Haddad, executive director of the Florida Academy of Sciences, which helped start up Orlando's original cafe and organizes the events.

"You're going to engage the (National Public Radio) crowd very easily here," said Linda Walters, a marine conservation biologist from the University of Central Florida who has lectured twice at the Orlando-area science cafes.

Haddad said the current national push to increase the number of U.S. graduates in science, technology, engineering and math, or the STEM fields, is driving up the number of science cafes.

In Orlando, an Orange County STEM Council consisting of business, government and educational leaders recently asked Haddad to help two interested parties launch new science cafes in the downtown library and in a large new town development.

The U.S. science cafe movement grew out of Cafe Scientifique in the United Kingdom. The first Cafe Scientifique popped up in Leeds in 1998 as a regularly scheduled event where all interested parties could participate in informal forums about the latest in science and technology.

Traditionally held in pubs and restaurants, the Cafe Scientifique would start as a short lecture, followed by a short break to refill glasses, and then an open discussion, according to the organization's website.

The American movement of independent cafes is loosely organized at the sciencecafe.org website created by public broadcaster WGBH's NOVA science program. Haddad said NOVA several years ago provided a few hundred dollars of seed money to groups around the country that wanted to start a cafe.

However, anyone with a venue, a speaker and a marketing plan can start one. On the sciencecafe.org website, an interactive map shows the location of cafes across the United States and around the globe from Islamabad, Pakistan, to Antwerp, Belgium, to the Hawaiian islands.

Some cafes have cropped up in bookstores, theaters and high school campuses.

In Viera, Fla., about 60 mostly retirees regularly pack a pizzeria to hear speakers from the well-regarded Brevard Zoo or NASA's nearby Kennedy Space Center. In Daytona Beach, scientists from the internationally known Embry-Riddle Aeronautical University draw standing-room-only crowds at a local coffee shop.

Haddad said his hope for the cafes is to engage the public and generate excitement about the STEM fields that might filter down to the next generation.

"My feeling is STEM begins at home, with students who are being brought up by parents or relatives who have some interest in science and may encourage them to do that," Haddad said.

Attending a cafe does not guarantee a speaker as engaging as the popular host of television programs Bill Nye the Science Guy, as Walsh learned when he got lost in the extensive jargon of one lecture.

"I don't know that every scientist is gifted with the ability to work a crowd as well as deliver a lecture on targeted radiation therapy for tumors," said Walsh. "If you can find one that hits both those things, they should have their own television show."

Dmitry Bogdanov

The ancient newfound crocodilian Tyrannoneustes lythrodectikos (shown here in an artist's rendering) would have devoured giant prey some 165 million years ago.

By Charles Choi
LiveScience

Long-forgotten remains of a giant dolphin-shaped crocodilian "super-predator" that could devour ancient beasts its size and larger have now been discovered in a museum drawer in Scotland, researchers say.

The ancient newfound crocodilian is named Tyrannoneustes lythrodectikos, which in ancient Greek means "blood-biting tyrant swimmer."

"Tyrannoneustes was a dolphinlike crocodile that lived 165 million years ago," said researcher Mark Young, a vertebrate paleontologist at the University of Edinburgh in Scotland and the University of Southampton in England.

The predator possessed a long snout, large flippers, armorless skin and a tail fin where the bottom half is larger than the top half, resembling an upside-down version of an ordinary shark's tail fin. It's uncertain how large Tyrannoneustes was, but the right side of its lower jaw was at least 26 inches (67 centimeters) long.

Tyrannoneustes was a super-predator, meaning it evolved to devour prey its size and larger. Features of its lower jaw and teeth reveal the beast was suited for swallowing smaller prey whole or slicing larger prey into pieces small enough to swallow. [ Image Gallery: Ancient Monsters of the Sea ]

"These features include enlarged teeth, teeth with serrated edges and a change in the shape of the lower jaw that allowed it to open wider," Young told LiveScience.

Mark Young

It's uncertain how large the super-predator Tyrannoneustes was, but the right side of its lower jaw (shown here) was at least 26 inches (67 cm) long.

Back when Tyrannoneustes was alive, the area in central England where the fossils were discovered was covered in a shallow sea encompassing much of what is now Europe.

"At that time, Europe would have been an archipelago with some larger landmasses," Young said. Europe was also farther south back then, meaning sea-surface temperatures were balmy, ranging from 68 to 80 degrees Fahrenheit (20 to 27 degrees Celsius). The area Tyrannoneustes was found in also held a diverse group of other marine reptiles, such as other marine crocodilians, the vaguely Loch Ness Monster-shaped plesiosaurs and pliosaurs, and the dolphin-shaped ichthyosaurs, as well as fish and squid.

The fossils were originally discovered in clay pits by fossil hunter Alfred Leeds some time between 1907 and 1909. They languished in a drawer in the Hunterian Museum and Art Gallery in Glasgow, Scotland, until Young and his colleagues rediscovered them.

"It had lain there for almost 100 years," Young said.

No modern crocodiles are descended from Tyrannoneustes. Instead, this predator was a kind of metriorhynchid, an extinct family of marine crocodiles.

"This new species fills an evolutionary gap in the metriorhynchid fossil record," Young said. "The discovery of Tyrannoneustes shows that during the Middle Jurassic, metriorhynchid crocodiles were beginning to evolve into predators of large-bodied prey. By the Late Jurassic, numerous metriorhynchid species were suited to feeding on large prey, but Tyrannoneustes is the first known from the Middle Jurassic. How this impacted upon other predatory groups such as pliosaurs and ichthyosaurs is still unclear."

Future research can scan Tyrannoneustes bones to develop computer models of how it might have fed, Young said. He and his colleagues detailed their findings online Jan. 4 in the Journal of Systematic Palaeontology.

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• 6 Strange Species Discovered in Museums
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Nina Dronkers

The speechless patient called "Tan" who allowed Paul Broca to tie a specific brain region to language has been identified as Louis Leborgne.

By Tia Ghose
LiveScience

The identity of a mysterious patient who helped scientists pinpoint the brain region responsible for language has been discovered, researchers report.

The new finding, detailed in the January issue of the Journal of the History of the Neurosciences, identifies the famous patient as Monsieur Louis Leborgne, a French craftsman who battled epilepsy his entire life.

Wordless patient
In 1840, a wordless patient was admitted to the Bicêtre Hospital outside Paris for  aphasia, or an inability to speak. He was essentially just kept there, slowly deteriorating. It wasn't until 1861 that the man, who came to be known as Monsieur Leborgne, or "Tan," for his only spoken word, came to the famous physician Paul Broca's ward at the hospital.

Shortly after the meeting, Leborgne died, and Broca performed his autopsy. During the autopsy, Broca found a lesion in a region of the brain tucked back and up behind the eyes. 

Paradigm shift
After doing a detailed examination, Broca concluded that Tan's aphasia was caused by damage to this region, and that the particular brain region controlled speech. That region of the brain was later renamed Broca's area in honor of the doctor. [See Photos of Broca's Brain ]

At the time, scientists were debating whether specific areas of the brain performed specific functions, or whether it was an undifferentiated lump that did one task, like the liver, said Marjorie Lorch, a neurolinguist at Birkbeck, University of London, who was not involved in the study.

"Tan was the first patient whose case proved that damage to a specific part of the brain causes specific speech disorders," said study author Cezary Domanski, a medical historian at the Maria Curie-Sklodowska University in Poland.

Life reconstructed
Yet Tan's identity remained shrouded in mystery. Most historians believed he was a poor, illiterate laborer, while others said he had gone mad from syphilis and that madness could explain his inability to speak. To discover just who he was, Domanski began to retrace the man's history.

"It was a challenge, for 150 years no one could even determine the name of the man —the same man whose brain is exhibited in a museum and shown in many books," Domanski wrote in an email.

But looking through the old medical records, he finally uncovered a death certificate for Louis Victor Leborgne, who was born in 1809 in Moret, France.

Domanski then used archival records to discover that Louis Leborgne was one of seven children of a teacher (his father) and his wife, and that his siblings were educated. He moved to Paris as a child.

Leborgne had apparently suffered epilepsy from childhood. But despite his seizures, he grew up to be a craftsman and a church keeper, and worked there until he was 30 years old, when he lost the ability to speak and was taken to the hospital. Epilepsy likely caused the damage that took away Leborgne's power of speech. [ The 10 Greatest Mysteries of the Mind ]

In the hospital, his condition worsened and he eventually became paralyzed and bedridden, and underwent surgery for gangrene. He was dying when Broca first encountered him.

The new discovery gives a very human identity to one of the medical textbooks' most famous cases, Lorch told LiveScience.

"Language, because it was viewed at that time in Europe as a God-given ability in humans, it was considered part of the soul and therefore not material," Lorch said. "This case was the case that really established the whole area of research on functional organization of the brain."

Follow LiveScience on Twitter @livescience. We're also on Facebook  and Google+.

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featurepics.com

Cats kill between 1.4 billion and 3.7 billion birds and between 6.9 billion and 20.7 billion small mammals yearly, according to new research.

By Tia Ghose
LiveScience

Cats kill billions of birds every year and even more tiny rodents and other mammals in the United States, a new study finds.

According to the research, published Tuesday in the journal Nature Communications, cats kill between 1.4 billion and 3.7 billion birds and between 6.9 billion and 20.7 billion small mammals, such as meadow voles and chipmunks.

Though it's hard to know exactly how many birds live in the United States, the staggering number of bird deaths may account for as much as 15 percent of the total bird population, said study co-author Pete Marra, an animal ecologist with the Smithsonian Conservation Biology Institute.

Staggering toll
Marra and his colleagues are looking at human-related causes for bird and wildlife deaths in the country, from windmills and glass windows to pesticides.

But first, Marra and his team looked at the impact of the feline population, one of the biggest putative causes of bird demise in the country.       

While past studies had used critter cams or owner reports to estimate the number of birds killed by cats, those studies were usually small and not applicable to the entire country, Marra told LiveScience.

For this broader analysis, the team first looked at all prior studies on bird deaths and estimated that around 84 million owned-cats live in the country, many of which are allowed outdoors. [ In Photos: America's Favorite Pets ]

"A lot of these cats may go outside and go to 10 different houses, but they go back to their house and cuddle up on Mr. Smith's lap at night," Marra said.

Based on an analysis of past studies, the researchers estimated that each of those felines killed between four and 18 birds a year, and between eight and 21 small mammals per year.

But the major scourges for wildlife were not those free-ranging, owned-cats, but instead feral and un-owned cats that survive on the streets. Each of those kitties — and the team estimates between 30 million and 80 million of them live in the United States — kills between 23 and 46 birds a year, and between 129 and 338 small mammals, Marra said.

And, it seems, the small rodents taken by felines aren't Norway rats or apartment vermin, but native rodent species such as meadow voles and chipmunks, he added.

No easy answers
One obvious step to reduce the mass wildlife death is to keep kitties indoors, Marra said.

Perhaps seeing their furry friends bring in a meadow vole or a cardinal will spur cat owners to say, "Listen, Tabby, we're going to have a heart-to-heart talk about how much time you spend outside," he said.

Wild cats pose tougher questions, because capture and sterilization approaches have varying levels of success depending on the community, said Bruce Kornreich, a veterinarian at Cornell University's Feline Health Center, who was not involved in the study.

While keeping owned-cats indoors is the best way to benefit both kitties and wildlife, a complete cat ban, like the one recently proposed in New Zealand, is probably not the answer, he said.

For one, it's not clear how completely removing cats from outdoors would affect the ecosystem.

"It may be in some cases that cats may also be keeping other species that may negatively impact bird and other small mammal populations in check," Kornreich told LiveScience.

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Mark Elbroch

An adult male Andean condor in flight.

By Douglas Main
Our Amazing Planet

A bill has been introduced to the Peruvian Congress that would protect Andean condors, a huge species of raptor that is in decline and in danger of dying out in some parts of its territory.

Backers of the bill would like to do away with an Andean ritual in which condors are strapped to the backs of raging bulls, which conservationists say hurts and kills the birds, according to Andean Air Mail & Peruvian Times, a regional news website. The law would declare the birds a "national treasure" and implement jail sentences for anybody who hurts or kills one.

Andean condors are some of the largest birds on Earth, with 10-foot (3 meter) wingspans. They can fly up to 100 miles (160 kilometers) in a single day, and they feed on the remains of dead animals such as cattle and other large mammals. The birds inhabit the Andes Mountains, ranging as far north as Colombia and south to Patagonia. There are about 10,000 condors left, and they are classified as "near threatened" by the International Union for Conservation of Nature. 

The bill targets a ritual called the "yawar" festival, in which a condor, representing indigenous people, is tied to the back of a wild bull, representing colonists, according to Reuters. The clawing of the bird enrages the bull; townspeople then take turns running in front of the angry bovine. It's unclear exactly how the ritual affects the birds, according to the news service, although some scientists say it leaves the condors too traumatized or injured to survive.

There are probably no more than 500 condors in Peru, and the population is in decline, according to the Peruvian Times. The bird's population takes a while to grow since the animals are long-lived and reproduce infrequently. The bill would lead to a captive breeding program for the condors, according to the Times.

The Andean people have held Condors sacred for thousands of years. A 445-foot (135 m) depiction of a condor is one of the best known Nazca Lines, the geoglyphs mysteriously carved into the Peruvian desert more than 1,500 years ago, according to Reuters. Quechua-speaking communities throughout the Andes consider the bird sacred.

The bill was sponsored by Peruvians who live near Colca Canyon, a popular tourist destination twice as deep as the Grand Canyon, now home to just 25 condors, a fraction of those seen in years past, Reuters reports. The Colca Canyon Provincial Mayor Elmer Cáceres said his province slaughters donkeys every week and leaves them as food for the condors, according to the Peruvian Times.

He told that site that some 80 percent of the region's visitors come to see the birds, and asked Peruvian supporters of the legislative initiative to visit the province's website and sign a petition to save the condor. It's too early to say if, or when, the bill might be passed, according to reports.

Reach Douglas Main at dmain@techmedianetwork.com. Follow him on Twitter @Douglas_Main. Follow OurAmazingPlanet on Twitter @OAPlanet. We're also on Facebook and Google+.

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Karl Tate, LiveScience infographic artist

An artist's interpretation of Bigfoot.

By Benjamin Bradford
LiveScience.com

Do new recordings from Oregon's Blue Mountains offer good evidence of the mysterious bipedal creature known as Bigfoot? That's what some are claiming after hearing a recording of strange roars and shrieks given to The Oregonian newspaper.

When people think of Bigfoot evidence, casts of big footprints and blurry photos and films often come to mind. But some of the more interesting bits of evidence are sound recordings of alleged vocalizations. One company, Sierra Sounds, markets a CD called "The Bigfoot Recordings: The Edge of Discovery." Narrated by "Star Trek" actor Jonathan Frakes, the recording claims to have captured vocalizations among a Bigfoot family.

The sounds include a series of guttural grunts, howls and growls. The liner notes offer testimonials from a "linguist" whose self-described credentials include playing the flute, speaking several languages and having "a Russian friend (who) thinks I'm Russian."

She confidently asserts that the tapes are not faked, and that the vocal range is too broad to be made by a human. She also suggests that Bigfoot individuals have a language, possibly including "Sasquatch swear words."

In his 1992 book "Big Footprints: A Scientific Inquiry Into the Reality of Sasquatch" (Johnson Books, 1992), physical anthropologist Grover Krantz discussed his experience with Bigfoot recordings: "One ... tape was analyzed by some university sound specialists who determined that a human voice could not have made them; they required a much longer vocal tract. A Sasquatch investigator later asked one of these experts if a human could imitate the sound characteristics by simply cupping his hands around his mouth. The answer was yes." As for other such recordings, Krantz "listened to at least 10 such tapes and find(s) no compelling reason to believe that any of them are what the recorders claimed them to be."

It's little wonder that one of the top scientific Bigfoot investigators held audio recordings in low regard: Sounds are simply poor evidence. [ Infographic: Tracking Belief in Bigfoot ]

Other explanations for the Blue Mountain sounds include foxes and coyotes, which — unlike Bigfoot — are known to exist in the area. Just because an animal call seems unusual or mysterious doesn't mean that it is. There are many factors than can affect how something sounds from far away, including temperature, wind and geographical features such as canyons.

Some suggest perhaps a hoaxer in the area is having a bit of fun with the local legend. And sometimes Bigfoot hunters go deep into the woods and "sound blast" pre-recorded "Bigfoot calls," hoping to elicit responses from any real Bigfoot nearby. Of course other people in the area can also hear the strange shrieks and howls coming from the dark wilderness and — not knowing that Bigfoot noisemakers are afoot — may report the sounds as genuine and unknown.

Acoustics and Bigfoot
According to "Good Morning America's" John Muller, this latest recording is not the only one; in fact the mysterious sounds have been coming out of the area since at least November. This raises an obvious question: If anyone seriously believes these sounds could be real evidence for Bigfoot, why haven't investigators been able to photograph or videotape the source of the sounds?

For example the cast of the optimistically titled Animal Planet show "Finding Bigfoot" has spent months in that area, and so far have come up empty-handed. Surely a well-financed cable television show would be able to provide its team members with the equipment they need; Neal Karlinsky of ABC News noted that the "Finding Bigfoot" crew has "every bit of cutting edge technology — night vision gear and all the sensors they can get their hands on." So what's the problem?

This isn't rocket science; it's the science of acoustics. With an array of sensitive microphones placed strategically throughout an area, it's relatively simple to triangulate the location of a sound to within a few feet almost instantly. If that same area is also covered by an array of wide-angle, high-resolution cameras (using infrared at night), it should be fairly simple to trigger cameras nearest the source of the sound to photograph whatever created it: fox, hoaxer, Bigfoot or something else.

Researchers could even use camera-mounted drones to help locate the vocalizations and monitor the area. Another option would be to set up a perimeter around areas where Bigfoot are said to be especially active and use sound-activated cameras. [ Rumor or Reality: The Creatures of Cryptozoology ]

Surely a group of 8- to-10-foot tall hairy bipedal animals can't be that hard to find if you place cameras around a hotspot of activity and wait a few weeks. Of course covering huge swaths of wilderness would not be cheap. But it would be a small price to pay if it finally provides hard evidence of Bigfoot — instead of more ambiguous roars, grunts and howls in the wilderness.

Benjamin Radford is deputy editor of "Skeptical Inquirer" science magazine and author of six books including "Tracking the Chupacabra: The Vampire Beast in Fact, Fiction, and Folklore." His Web site is www.BenjaminRadford.com.

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Michael Euler / AP

Rolf-Dieter Heuer, director general for Europe's CERN particle physics center, gestures as he speaks during an interview with The Associated Press at the World Economic Forum in Davos, Switzerland, on Saturday.

DAVOS, Switzerland — The world should know with certainty by the middle of this year whether a subatomic particle discovered by scientists is a long-sought Higgs boson, the head of the world's largest atom smasher says.

Rolf Heuer, director of the European Organization for Nuclear Research, or CERN, said he is confident that "towards the middle of the year, we will be there." By then, he said reams of data from the $10 billion Large Hadron Collider on the Swiss-French border near Geneva should have been assessed.

The timing could also help Scottish physicist Peter Higgs win a Nobel Prize, Heuer said in an interview with The Associated Press in the Swiss resort of Davos on Saturday.

CERN's atom smasher helped scientists declare in July their discovery of a new subatomic particle that Heuer calls "very, very like" a Higgs boson, that promises a new realm of understanding the universe.

The machine, which has been creating high-energy collisions of protons to investigate dark matter, antimatter and the creation of the universe, is being put to rest early this year. The data from it, however, takes longer to analyze.

"Suppose the Higgs boson is a special snowflake. So you have to identify the snowflake, in a big snowstorm, in front of a background of snowfields," Heuer said by way of analogy. "That is very difficult. You need a tremendous amount of snowfall in order to identify the snowflakes and this is why it takes time."

He said the Standard Model of particle physics describes only 5 percent of the universe, which many theorize occurred in a massive explosion known as the Big Bang.

To explain how subatomic particles, such as electrons, protons and neutrons, were themselves formed, Higgs and others in the 1960s envisioned an energy field where particles interact with a key particle, the Higgs boson.

The idea was that other particles interact with Higgs bosons, and the more they interact, the bigger their mass will be. But a big question remains: Is this new particle a variation of the Higgs boson, or the same as the single Higgs boson that was predicted?

The phrase "God particle," coined by Nobel Prize-winning physicist Leon Lederman, is used by laymen, not physicists, more as an explanation for how the subatomic universe works than how it all started.

"Now, if there is a deviation in one of the properties of this Higgs boson, that means we open a new window, for example, hopefully into the part of the dark universe, the 95 percent of the unknown universe," said Heuer.

"If you find the deviation," he added, "that means if it is not the — but a — Higgs boson, then we might find a fantastic window into the dark universe so we would make another giant leap from the visible to the dark."

Copyright 2013 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. 

Kyodo via Reuters

A Japanese H-2A rocket carrying an information-gathering radar satellite blasts off from its island launch pad at Tanegashima Space Center.

TOKYO — Japan launched two intelligence satellites into orbit on Sunday amid growing concerns that North Korea is planning to test more rockets of its own and possibly conduct a nuclear test.

Officials say the launch Sunday of the domestically produced H2-A rocket went smoothly, and the satellites — an operational radar satellite and an experimental optical probe — appear to have reached orbit.

Japan began its intelligence satellite program after North Korea fired a long-range missile over Japan's main island in 1998. North Korea conducted a launch last month that it says carried a satellite into orbit but has been condemned by the United States and others as a cover for its development of missile technology.

The latest Japanese launch was in the planning stages long before the current increase in tensions with North Korea, but underscores Japan's longstanding wariness of its isolated neighbor's abilities and intentions.

The radar satellite, which can provide intelligence through cloud cover and at night, is intended to augment a network of several probes that Japan already has in orbit. The optical probe will be used to test future technology and improvements that would allow Japan to strengthen its surveillance capabilities.

Japan still relies on the United States for much of its intelligence.

Its optical satellites are believed to be about as good as commercial satellites, meaning they are able to detect objects of about 40 centimeters (16 inches) in size from their orbits. With the additional radar satellite, Japan hopes to be able to glean intelligence on any specified location once a day.

Japan, which hosts about 50,000 U.S. troops, is especially concerned about North Korea because its main islands are already within range of the North's missiles. Along with developing its own network of spy satellites, Japan has cooperated with Washington in establishing an elaborate missile defense shield.

North Korea's powerful National Defense Commission declared last week that the country would carry out a nuclear test and launch more rockets in defiance of the U.N. Security Council's announcement that it would punish Pyongyang for its long-range rocket test in December with more sanctions, calling it a violation of a ban on nuclear and missile activity.

North Korea's state news agency said on Sunday that leader Kim Jong Un vowed at a meeting of top security and foreign officials to take "substantial and high-profile important state measures."

Copyright 2013 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.