National Geographic Tales of the Weird

by David Braun

  In research published in the journal Nature, Kacelnik and his colleagues demonstrated that New Caledonians are born toolmakers—that there is a genetic component to the behavior. The finding, Kacelnik said, fits the notion that higher intelligence requires a genetic imprint to foster more advanced behaviors like learning and innovation.

  “There are three elements: what animals inherit, what animals learn by individual experience, and what animals acquire through social input,” he said. “It’s a mistake to believe [these elements] compete. Actually, they coalesce, they enhance each other.”

  TRUTH:

  CROWS ARE VERY SOCIAL AND LIVE IN FAMILY GROUPS CONSISTING OF BETWEEN 2 AND 15 BIRDS, WITH 4 BEING THE AVERAGE.

  Crow Trickery

  The intelligence of other crow species, most notably ravens, is also demonstrated by their ability to manipulate the outcomes of their social interactions, according to book author Savage.

  For example, she highlights raven research by University of Vermont zoologist Bernd Heinrich showing how juvenile and adult ravens differ when feeding on a carcass. The juveniles cause a ruckus when feeding to recruit other young ravens to the scene for added safety against competition with adult crows and other scavengers. The adults, by contrast, show up at a carcass in pairs and keep quiet to avoid drawing attention—and competition—to the food.

  Savage also discusses Swiss zoologist Thomas Bugnyar’s research showing how a raven named Hugin learned to deceive a more dominant raven named Mugin into looking for cheese morsels in empty containers while Hugin snuck away to raid full containers.

  “This shady behavior satisfies the definition of ‘tactical,’ or intentional, deception and admits the raven to an exclusive club of sociable liars that in the past has included only humans and our close primate relatives,” Savage writes in her book.

  Another area of crow research that may indicate higher intelligence is how crows learn and use sound. Preliminary findings suggest that family groups develop their own sort of personal dialects, according to Savage. “There’s a lot more going on in a bird brain than people ten years ago would have imagined,” she said.

  BARE-NECKED BIRDS

  Why Transylvanian Chickens Have Naked Necks

  Some say “churkeys,” some say “turkens,” but science says that a genetic mutation is behind the bare-naked necks of Transylvanian chickens.

  Scientists have cracked why the Transylvanian naked neck chicken has a featherless neck—and it isn’t to give vampires easier access. The Transylvanian bird’s bare neck results from a random genetic mutation that causes the overproduction of a feather-blocking molecule called BMP12, a new DNA study shows.

  TRUTH:

  MIKE THE CHICKEN LIVED FOR 18 MONTHS WITHOUT A HEAD, FROM 1945 TO 1947.

  Churkeys and Turkens

  The mutation first arose in domestic chickens in northern Romania hundreds of years ago. The naked neck chicken-also dubbed the churkey or turken—has a chickenlike body but a turkeylike head atop a long, deep-red neck.

  Surprisingly when scientists treated standard-breed chicken embryos with BMP12 in the lab, the young chickens developed no feathers on their necks—suggesting the neck is more sensitive to the molecule, according to study leader Denis Headon, a developmental biologist at the University of Edinburgh’s Roslin Institute.

  Transylvanian naked neck chickens’ vampire-friendly look is genetic. (Photo Credit 6.10)

  To find out why, Headon and his team did a further analysis, which revealed that an acid derived from Vitamin A is produced on the chicken’s neck skin. The acid essentially enhances the BMP molecule’s effects, making the birds’ necks bare, they found.

  Naked Necks, Cooler Birds

  Unlike most genetic mutations, which are generally bad for an animal, the naked-neck tweak has increased naked necks’ popularity worldwide. That’s because bare-necked birds are more resistant to heat and thus produce better meat and eggs—especially crucial for poultry producers in hot climates such as Mexico, Headon said.

  And naked necks aren’t alone: “We think all birds have this priming or readiness to lose neck feathers first,” he noted. “Once you have a mutation that increases BMP12 in skin, the neck is the region that’s ready to lose its feathers—it’s already more sensitive.”

  In the wild, for instance, it’s likely that ostriches and storks have lost their neck feathers to stay cool, though it’s unclear whether BMP12 played any role. “Evolution has always found it easy to lose neck feathers whenever it gets hot and the bird gets big.”

  CHAPTER 7

  The Final Frontier

  (Photo Credit 7.1)

  A long time ago, in a galaxy far, far away … there were some weird things happening. They are still happening—in our own galaxy and in many, many others. There are the cannibal stars that snack on their neighbors, the discovery of a “diamond” exoplanet, and light, fluffy snow found on the moons of Saturn. These things may sound like they’re straight out of science fiction, but they’re not. They’re the cold, hard, weird truth.

  WATER FROM SPACE

  What Created Earth’s Oceans?

  Comet Offers New Clue

  Was Earth’s water delivered from above? Astronomers believe they know the answer.

  For the first time, astronomers have found water on a comet that’s a chemical match for water on Earth, a new study says. The discovery backs up theories that water-rich comets helped fill ancient Earth’s oceans.

  A close-up of peanut-shaped Hartley 2 (Photo Credit 7.2)

  They Ain’t Semiheavy

  Planet-formation models indicate that early Earth was much too hot to sustain liquid water on its surface, making the origin of Earth’s oceans a mystery. So scientists speculated that our planet’s surface water came from comets that slammed into Earth once the planet had cooled.

  This theory was dealt a serious blow in the 1980s, however, due to measurements of the ratio of normal to “semiheavy” molecules—the D/H ratio—in comet water. In a semiheavy water molecule, one hydrogen atom (H) is replaced with a heftier version called deuterium (D). All water in nature has a D/H ratio, and since deuterium is a very stable atom, this ratio can go unchanged for eons.

  Since the 1980s, researchers have found that several comets in our solar system have D/H ratios that are very different from that of Earth’s water. Those results indicated that, at best, only about 10 percent of Earth’s water could have come from comets, with the rest probably coming from water-rich asteroids, explained study leader Paul Hartogh, an astronomer at the Max Planck Institute for Solar System Research in Germany.

  “The reservoir of Earth ocean-like material is much larger than we thought, and it encompasses cometary material, which we hadn’t recognized. We have to think really hard and try to get a better understanding of what is going in our Solar System, and whether you can really rule out comets as the source of Earth’s water.”

  Ted Bergin

  University of Michigan

  Molecular Match

  In the new study, Hartogh and his team used the European Space Agency’s Herschel Space Observatory to examine the D/H ratio of the comet 103P/Hartley 2. Hartley 2 is a so-called Jupiter family comet because its orbit takes the comet close to the orbits of Jupiter and the other gas giants.

  The results show that Hartley 2’s water is very similar to that of Earth. Importantly, computer simulations suggest that Hartley 2 originated from the Kuiper belt, a region beyond the orbit of Neptune that is filled with comets and other icy remnants from the formation of our solar system.

  This would suggest that the larger group of comets that helped form Earth’s oceans originally came from the Kuiper belt. By contrast, the comets with D/H ratios that didn’t match Earth’s are thought to have originated in the Oort cloud, a reservoir of billions of comets that astronomers think exists far beyond the Kuiper belt.

  TRUTH:

  IT WOULD TAKE A STACK OF MORE THAN NINE EMPIRE STATE BUILDINGS TO EQUAL THE AVERAGE DE
PTH OF THE OCEAN.

  Other Space Sources

  Finding a comet that’s a match for Earth suggests more such matches may be out there, which means much more of our planet’s water could have come from comets after all, Hartogh said. But exactly how much is still unclear and will require further studies.

  “We cannot give a number,” Hartogh said. “In principle, all of Earth’s water may [have] come from comets. However, it is still possible that a large—or the largest—fraction came from asteroids.”

  ANOTHER EARTH?

  New Planet May Be Among Most Earthlike

  Weather Permitting

  A new planet found about 36 light-years away could be one of the most Earthlike worlds yet—if it has enough clouds, a new study says.

  The search for Earthlike planets is one of the most exciting challenges facing astronomers today, and the clouds on one of the latest discoveries, the unpoetically named HD85512b, have captured their attention.

  An artist’s impression of a “Super Earth” orbiting the sunlike star HD85512b (Photo Credit 7.3)

  Liquid Water Likely

  HD85512b was discovered orbiting an orange dwarf star in the constellation Vela. Astronomers found the planet using the European Southern Observatory’s High Accuracy Radial velocity Planet Searcher, or HARPS, instrument in Chile.

  Radial velocity is a planet-hunting technique that looks for wobbles in a star’s light, which can indicate the gravitational tugs of orbiting worlds. The HARPS data show that the planet is 3.6 times the mass of Earth, and the new world orbits its parent star at just the right distance for water to be liquid on the planet’s surface—a trait scientists believe is crucial for life as we know it.

  “The distance is exactly the limit where you want to be to have liquid water,” said study leader Lisa Kaltenegger of the Harvard-Smithsonian Center for Astrophysics and the Max Planck Institute for Astronomy. “If you scale it to our system, it’s a bit farther out than Venus is to our sun.” At that distance, the planet likely receives a bit more solar energy from its star than Earth does from the sun.

  Earths Galore?

  HD85512b is one of 16 super-Earths that the European Southern Observatory recently discovered using the High Accuracy Radial velocity Planet Searcher (HARPS). Super-Earths are planets whose mass is between one and ten times that of Earth, but whether life exists there requires exploration. Michel Mayor, who led the HARPS team, says, “In the coming 10 to 20 years we should have the first list of potentially habitable planets in the sun’s neighborhood. Making such a list is essential before future experiments can search for possible spectroscopic signatures of life in the exoplanet atmospheres.”

  Cloud Cover

  But Kaltenegger and colleagues calculate that a cloud cover of at least 50 percent would reflect enough of the energy back into space to prevent overheating. On average, Earth has 60 percent cloud cover, so partly cloudy skies on HD85512b are “not out of the question,” she said.

  Of course, clouds of water vapor depend on the presence of an atmosphere similar to Earth’s, something that can’t be detected on such distant planets with current instruments. Models of planet formation predict that planets with more than ten times Earth’s mass should have atmospheres dominated by hydrogen and helium, Kaltenegger said. Less massive worlds—including HD85512b—are more likely to have Earthlike atmospheres, made mostly of nitrogen and oxygen.

  Location, Location, Location

  So far, the newly detected planet is the second rocky world outside our solar system to be confirmed in its star’s habitable zone—the region around a star that’s not too hot and not too cold for liquid water. The first, planet Gliese 581d, was previously discovered using the HARPS instrument. This world lies just on the cool edge of its star’s habitable zone.

  Another promising planet, Gliese 581g, was discovered in 2010 and dubbed the most Earthlike planet yet. But controversy surrounds the claim, with some experts declaring that the entire planet is actually a data glitch. Manfred Cuntz, director of the astronomy program at the University of Texas, Arlington, noted that more information is needed before anyone can speculate whether aliens are wandering around the newfound planet. “It’s not their fault no extra information [about the planet’s atmosphere] is available right now,” Cuntz said of the research team. “It looks like this is a strong candidate, in principle.”

  TRUTH:

  DAYS ARE LONGER THAN YEARS ON THE PLANET MERCURY.

  Potential for Life

  In addition to size and location, HD85512b has two other points in its favor for potentially harboring life, Cuntz said. The planet’s orbit is nearly circular, which would provide a stable climate, and its parent star, HD85512, is older—and therefore less active—than our sun, which would lower the likelihood of electromagnetic storms damaging the planet’s atmosphere.

  Not only that, but in principle, the age of the system—5.6 billion years—“gives life a chance to originate and develop,” he said. By contrast, our own solar system is thought to be about 4.6 billion years old.

  A Great Place for Yoga?

  Given current limits on space travel, it’s unlikely for now that humans will get to visit HD85512b. But if we could get there, the newfound planet might seem like a fairly alien world: muggy, hot, and with a gravity 1.4 times that of Earth’s, study leader Kaltenegger said. On the bright side, “Hot yoga might be one of the things you don’t have to pay for there,” she quipped.

  SLEEPING SUN

  Sun Headed into Hibernation

  Solar Studies Predict

  There’s been a recent flurry of sunspot activity, but scientists believe it’s the storm before the calm. The sun may be going on a break.

  Enjoy our stormy sun while it lasts. When our star drops out of its latest sunspot activity cycle, the sun is most likely going into hibernation, scientists announced.

  A quiet sun: Very few active regions are visible in this 2009 satellite picture. (Photo Credit 7.4)

  Solar Cycle Slow Down

  Three independent studies of the sun’s insides, surface, and upper atmosphere all predict that the next solar cycle will be significantly delayed—if it happens at all. Normally the next cycle would be expected to start roughly around 2020. The combined data indicate that we may soon be headed into what’s known as a grand minimum, a period of unusually low solar activity.

  The predicted solar “sleep” is being compared to the last grand minimum on record, which occurred between 1645 and 1715. Known as the Maunder Minimum, the roughly 70-year period coincided with the coldest spell of the Little Ice Age, when European canals regularly froze solid and Alpine glaciers encroached on mountain villages.

  TRUTH:

  ABOUT A MILLION EARTHS COULD FIT INSIDE THE SUN.

  Headed for a Cold Snap?

  “We have some interesting hints that solar activity is associated with climate, but we don’t understand the association,” said Dean Pesnell, project scientist for NASA’s Solar Dynamics Observatory (SDO). Also, even if there is a climate link, Pesnell doesn’t think another grand minimum is likely to trigger a cold snap.

  “With what’s happening in current times—we’ve added considerable amounts of carbon dioxide and methane and other greenhouse gases to the atmosphere,” said Pesnell, who wasn’t involved in the suite of new sun studies. “I don’t think you’d see the same cooling effects today if the sun went into another Maunder Minimum-type behavior.”

  Sunspots Losing Strength

  Sunspots are cool, dark blemishes visible on the sun’s surface that indicate regions of intense magnetic activity. For centuries, scientists have been using sunspots—some of which can be wider than Earth—to track the sun’s magnetic highs and lows. For instance, 17th-century astronomers Galileo Galilei and Giovanni Cassini separately tracked sunspots and noticed a lack of activity during the Maunder Minimum.

  In the 1800s, scientists recognized that sunspots come and go on a regular cycle that lasts about 11 years. We’re now in Solar
Cycle 24, heading for a maximum in the sun’s activity sometime in 2013.

  Recently, the National Solar Observatory’s Matt Penn and colleagues analyzed more than 13 years of sunspot data collected at the McMath-Pierce Telescope at Kitt Peak, Arizona. They noticed a long-term trend of sunspot weakening, and if the trend continues, the sun’s magnetic field won’t be strong enough to produce sunspots during Solar Cycle 25, Penn and colleagues predict.

  “The dark spots are getting brighter,” Penn said. Based on their data, the team predicts that, by the time it’s over, the current solar cycle will have been “half as strong as Cycle 23, and the next cycle may have no sunspots at all.”

  TRUTH:

  A VOLCANIC ERUPTION IN 1883 MADE THE SUN LOOK GREEN.

  Sluggish Jet Streams

  Separately, the National Solar Observatory’s Frank Hill and colleagues have been monitoring solar cycles via a technique called helioseismology. This method uses surface vibrations caused by acoustic waves inside the star to map interior structure.