Thursday, 4 November 2010

Johnald's Fantastical Daily Link Splurge

Johnald's Fantastical Daily Link Splurge

Holographic Telecommuting May Soon Be Possible

Posted: 03 Nov 2010 12:46 PM PDT

A new holographic display can transmit three-dimensional movies from one location to another almost in real time. If Princess Leia had to send her "Help me Obi-Wan Kenobi, you're my only hope" message from Earth today, it would now be technologically possible.

"We can take objects from one location and show them in another location in 3-D in near real time," said optical scientist Nasser Peyghambarian, and project leader from the University of Arizona in a press conference Nov. 1. "It is no longer something that is science fiction, it is actually something that you can do today."

Holographic movies have been a dream since at least 1966, when the first hologram was transmitted over a television system by Bell Labs. Updatable holographic displays have been around for decades as well; the first was developed by Stephen Benton at the MIT Media Lab in 1989.

The new device projects a color 3-D image onto a sheet of special plastic using a fast-flashing laser. The image can be updated once every two seconds, fast enough to give a sense of movement.

"In the past, other holograms you have seen are static images," said Pierre-Alexandre Blanche of the University of Arizona, lead author of a study in the Nov. 4 Nature describing the device. "Now, with a 2-second lag, it starts to become something more tangible."

The image can also be transmitted over the internet in less than a second, which would allow a near real-time window into distant events, something the authors call "holographic telepresence."

 

Peyghambarian and colleagues set an array of 16 webcams in a semicircle around the objects they wished to project, which included a model airplane, a vase of flowers and the researchers' heads. Each camera captured the object from a different perspective, making the ultimate image more lifelike.

"If you go to a 3-D movie like Avatar, you would see only two perspectives, one for one eye and one for the other eye," Peyghambarian said. "In our case, we have demonstrated 16 perspectives, but the technology has the potential to show hundreds of perspectives. So it's very close to what humans can see."

The cameras sent the images to another room, where they were encoded into pulsed laser that flashes 50 times per second. Each laser pulse encodes one holographic pixel, or "hogel."

Then the researchers trained the laser onto a newly developed plastic called a photoreactive polymer, which is coated with a material that converts light into electrical charges that create and store the image. The charges move around the plastic in such a way that when light bounces off the material, it reaches your eyes as if it had bounced off the toy plane or the researcher's head.

"With this material, since you can move the charge around, you can erase the hologram and write another hologram on it," Blanche said.

Two years ago, Peyghambarian's team made a similar material that could only refresh the image every four minutes. The images in that material were also disturbed by vibrations and temperature changes, so the screen had to be kept in a highly controlled box.

The new material rewrites every two seconds, a 100-fold improvement, and isn't bothered by changes to its environment, the researchers say.

Beyond entertainment and fighting the Empire, the display could have important medical and military applications, Peyghambarian says.

"Different doctors from different parts of the world can participate [in surgery] and see things just as if they were there," he said. The device could even be used for telecommuting. "People from Europe don't have to come to the U.S. to participate in a conference, it would be as if they were there."

"This is mostly a materials advance," said optical scientist Michael Bove of the MIT Media Lab, who was not involved in the new research but is collaborating with Peyghambarian on another project. "The material is faster and more sensitive than what had previously been reported."

Given the small size of the screen and the two-second lag time, "some people in the field object to the term 'telepresence,'" Bove said.

Blanche agrees that the hologram's lag time is too long. "Quite frankly, it's a bit annoying, and we know that," he said.

For truly real-time video, the image would need to refresh 30 times a second. That would take either a much more sensitive material or a "very big, very nasty" laser, Blanche said. The team hopes to push the material to produce video quality holographs in the next two years, and the technology could be ready for your living room within the decade.

"In two years we improved the speed by a factor of 100. If we can improve the speed by the same factor, we will be over video rate," Blanche said. "It will be done."

Video: Blanche et al. Nature.

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Google Sky Adds Galaxy Clusters

Posted: 03 Nov 2010 10:54 AM PDT

Using Google Earth in Sky mode is a fun and interactive way to explore the universe. By importing images from space telescopes like Hubble and the Sloan Digital Sky Survey, Google Sky lets you fly deep into the visible universe for close-ups with planets, galaxies and star clusters.

But something's been missing, say astronomers Jiangang Hao and James Annis at the Fermi National Accelerator Laboratory. Google Sky's view of galaxy clusters is fuzzy and incomplete. That's because the program uses low-resolution pictures to speed up image transfer over the web. To have higher resolution images, you need to add in better pictures yourself.

Luckily, Hao and Annis have made this easy. They've loaded about 100 scans from one strip of the sky onto a public server at Fermilab, and made them available in Keyhole Markup Language (.kml files), the Google Earth equivalent of HTML files for web browsers. If you already have Google Earth, the whole thing takes a remarkably simple one-click download.

The full instructions are available in a paper posted to arXiv.org, and the files are posted on the team's website. Enjoy!

Image: Wired.com

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Giant Vicious-Looking Ancient Shrimp Was a Disappointing Wimp

Posted: 03 Nov 2010 09:57 AM PDT

If anything lurking in shallow Cambrian seas looked like a monster, Anomalocaris canadensis was it. The 3-foot-long, lobe-winged, shrimp-like creature came equipped with two barbed feelers and an armor-plated mouth — parts paleobiologists once thought were ideal for finding and crunching tasty trilobites.

But a new 3-D model of the creature's mouth parts, presented Nov. 1 at the Geological Society of America's annual meeting in Denver, Colorado, may restrict the ancient predator's diet only to mushy meals.

"We found that it's extremely unlikely Anomalocaris could eat most trilobites," said James Whitey Hagadorn, the research team's leader and a paleontologist at the Denver Museum of Nature and Science. "It couldn't close its mouth all of the way, its mouth was too soft to crush trilobite shells."

Jean Vannier, a paleontologist at Université Lyon 1 in France who was not involved in the work, said Hagadorn's conclusions make sense.

"What was the function of the powerful frontal appendages of Anomalocaris? They seem to be directed towards the mouth but there [is] no clear evidence that they might be used for crushing food," Caron wrote in an e-mail. "To me their main function might have been to stir up the bottom sediment."

 

Hagadorn said the mouth parts are often illustrated as capturing trilobites and other Cambrian critters, but emphasized that little if any research backs up the popular depiction. Instead of eating solid food, Hagadorn suspects Anomalocaris stuck to softer items on the menu 500 million years ago, much the same way modern arthropods such as shrimp, crabs and lobsters do.

"They mostly eat soft things, worms in the mud or soft microorganisms floating in water," Hagadorn said. "We have no positive evidence Anomalocaris did eat this way, but that's not surprising. How are you going to tell the difference between mushed-up worms, mushed-up phytoplankton or mushed-up snails in the fossil record? They're all going to look like mush."

To reconstruct Anomalocaris' ancient mouth parts, Hagadorn and his team examined 400 fossils of the structures, picked the best-preserved ones, then plugged the data into a 3-D computer model. They also did the same for 12 groups of trilobites, "including spiny ones, flat ones, round ones, and so on," Hagadorn said, noting the shell strength was modeled after crab and lobster shells.

"Basically, we tried to capture the full range of prey sizes and shapes as well as predator mouth sizes and shapes," he said.

The computerized model's stress tests showed Anomalocaris' two feelers were very inflexible and the armored mouth, at least for non-juvenile trilobites, would break before the trilobites did.

"There's that, plus no positive evidence in fossilized gut contents, feces or otherwise suggesting that Anomalocaris could eat trilobites or anything else with shells or cuticles," Hagadorn said.

Some trilobite fossils have bite marks and scars resembling Anomalocaris' nibble. Hagadorn suggested that perhaps the creature "ingested things and then spit them out," including hard-shelled trilobites, but never ate them.

Jean-Bernard Caron, a paleontologist at the Royal Ontario Museum in Toronto who was not involved in the work, said that doesn't mean Anomalocaris never ate trilobites, however.

"The animal was likely well-adapted for preying on soft preys," Caron wrote, noting that trilobites did shed their carapace during molting. "It is possible that they could have preyed upon them during that time … and before the carapace mineralized again, thus explaining numerous healed injuries on trilobites."

Paleobiologist Danita Brandt of Michigan State University in East Lansing, who was independent of the research team, joked that "no court of law" could convict a predator of trilobites. But she said Hagadorn's work is an important step in getting there.

"His model takes a lot of the guesswork out of the equation of what Anomalocaris was capable of," Brandt said. "I think what he's done here is fantastic."

Images: 1) Illustration of the bottom of Anomalocaris canadensis, with two feelers and an armor-plated mouth./Wikimedia Commons/Nobu Tamura. 2) Anomalocaris' distinctive pineapple-ring-like mouth, in the open position, with the four cardinal plates visible./Hagadorn et al. 3) Fossils of trilobites, creatures Anomalocaris may not have been able to eat while hard-shelled./Flickr/kevinzim.

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How Darwin’s Finches Keep Their Species Separate

Posted: 03 Nov 2010 09:47 AM PDT

The shifting songs of Darwin's finches have given new insight into processes that shape the course of evolution, preventing newly forked branches on life's tree from growing back together.

Even though it's biologically possible for Geospiza fortis and Geospiza scandens — the original residents of the Galapagos island of Daphne Major — to interbreed with newly arrived Geospiza magnirostris, the species have stayed separate.

The birds learned to sing new tunes, setting off a behavioral cascade that swept the island in just a few decades: Evolution in action, audible to the naked ear.

The findings, published October 31 in the Proceedings of the National Academy of Science, "throw light on what happens at a crucial stage in speciation," wrote Princeton biologists Rosemary and Peter Grant.

Since the late 1970s, the Grants have worked on Daphne Major, studying descendants of some of the same finches that inspired Charles Darwin's evolutionary theories.

Scattered on isolated islands, Galapagos finch species have diverged from a common ancestor over the last several million years. Enough time has passed for species to become physically distinct, adapted to the unique niches of their home islands.

 

Not enough time has passed, however, for interbreeding to become impossible. Yet finch species often keep to themselves, even when winds or migratory impulses carry them between islands.

That reproductive separation between geographically overlapping but biologically compatible species — technically known as allopatric speciation — is considered an important phase in species divergence. It keeps species apart long enough for their differences to become absolute. It's happened many times in the tree of life's divergence, but at time scales lost to prehistory.

In their new study, the Grants describe it in real-time.

When they arrived in 1978, G. fortis and G. scandens were Daphne Major's sole finch inhabitants. Five years later, G. magnirostris, arrived on the island. After several decades, a few of the original finches interbred, producing a hybrid that appears destined to become its own species. Yet neither bred with with G. magnirostris. According to the Grants, G. fortis and G. scandens maintained separation through song.

For the finches, as for so many birds, songs — sung by males, learned from their fathers — are a central form of communication. They enable individuals to recognize others of their species, advertising the possibility of reproduction. Each species' song is distinctive.

As it happened, the song of G. magnirostris originally overlapped with the tunes of G. fortis and G. scandens. That's no longer true. Since 1983, their trill rates, frequency and bandwidth have all changed drastically.

What's most intriguing about the change is that it doesn't seem to have a physical origin. The shapes of G. fortis and G. scandens beaks haven't changed, as might be expected. (After all, it was variations in finch beak form that so inspired Darwin.) Nor did their bodies change.

Instead the change was behavioral. The finches quickly learned new songs, demonstrating what researchers call "peak shift." Male finches first sing in imitation of their fathers; as they mature, they add new riffs, and teach those songs to their own sons — who, in turn, riff even further.

Peak shift represents a much more active, dynamic evolutionary mechanism than random genetic mutation. In just a few decades, all across the island, both G. fortis and G. scandens occupied a completely new acoustic space.

The Grants think peak shift may be a common evolutionary phenomenon, responsible for separating similar species for the millions of years necessary to become genetically incompatible.

"Behavioral modification of mate-signal learning, through a peak shift mechanism, without genetic change, may be widespread," they wrote.

Images: Top row, the three finch species on Daphne Major; below, the change since 1983 in the acoustic space occupied by their songs. G. fortis and G. scandens (red and green) now occupy very different ranges from G. magnirostris (blue)./Peter and Rosemary Grant.

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Citation: "Songs of Darwin's finches diverge when a new species enters the community: Implications for speciation." By B. Rosemary Grant, Peter R. Grant. Proceedings of the National Academy of Sciences, Vol. 107 No. 44, November 1, 2010.

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Shuttle Launchpad From Space: Discovery Awaits Liftoff

Posted: 03 Nov 2010 09:22 AM PDT

The Space Shuttle Discovery waits on the launch pad at the Kennedy Space Center in Florida for its final trip into space in this image captured by the GeoEye-1 satellite yesterday. The launch will mark Discovery's 39th journey, and NASA's 133rd shuttle mission overall. One final space shuttle launch is scheduled for Feb. 27, 2011, before NASA retires the shuttle fleet for good.

Discovery is scheduled to take off at 3:52 p.m. EDT on Wednesday, Nov. 3, but the Chicago Tribune reports an electrical glitch may push the launch back to Thursday or later.

Update: Discovery's launch has been delayed to 3:29 p.m. EDT on Thursday, Nov. 4.

Image: GeoEye

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Wednesday, 3 November 2010

Johnald's Fantastical Daily Link Splurge

Johnald's Fantastical Daily Link Splurge

Rare Dead Quasar Found in Nearby Galaxy

Posted: 02 Nov 2010 02:16 PM PDT

One of the universe's brightest lights, a black hole-driven quasar in a nearby galaxy, recently shut off like a snuffed candle.

New observations of a bizarre cloud of glowing gas, and a nearby galaxy that illuminates it, show that the galaxy's central light went dim sometime in the last 70,000 years. The finding could reveal how supermassive black holes help galaxies grow and evolve.

"This is the best view we will ever have of the host galaxy of a quasar," said astrophysicist Kevin Schawinski of Yale University, lead author of a paper published online Oct. 26 in Astrophysical Journal Letters and cofounder of the crowdsourced space science project Galaxy Zoo. "It's the nearest one to us, and the quasar is dead."

Quasars are ravenous, supermassive black holes that lurk at the centers of some galaxies and devour gas and dust from a surrounding disk. As the gas falls into the black hole, a process astronomers call accretion, friction heats the gas until it glows white-hot.

"Accretion transforms the darkest objects in the universe into the brightest," said black hole expert Chris Done of the University of Durham in the U.K., who was not involved in the new study. "It's like the final scream before it disappears forever below the event horizon."

Astronomers have long suspected that energy from quasars can help galaxies grow, a notion supported by the fact that bigger galaxies tend to have bigger central black holes. But until now, evolving galaxies have been impossible to observe.

 

A new clue comes from Hanny's Voorwerp, a weird cloud of glowing green gas found in Galaxy Zoo's archival telescope data in 2007. The Voorwerp (Dutch for "object" ) was thought to be lit up by a nearby quasar zapping it with a floodlight-like jet of ionizing radiation.

But there was no nearby quasar to be found. The closest object was a wimpy, dim galaxy called IC 2497 between 45,000 and 70,000 light-years away from the Voorwerp. Both objects are about 730 million light-years from Earth, "which cosmologically speaking is our backyard," Schawinski said.

There were two possible explanations for the missing quasar. Either there's so much gas and dust between Earth and the galaxy that the floodlight looks like a flashlight to us, but not to the Voorwerp, or the quasar died sometime between when its light hit the Voorwerp and now.

To test the first idea, Schawinski and colleagues observed the galaxy with two space telescopes, the Suzaku X-ray Telescope and the XMM-Newton X-ray observatory. These telescopes detect high-energy X-rays that would penetrate even the thickest clouds of dust.

The team did see a few X-rays, but it was "a really weak, puny little source," Schawinski said.

"This source is way way way too weak to light up the Voorwerp," he said. "It's like trying to light up your house with an LED. It's just not enough."

As it appears today, the quasar is 100 to 10,000 times dimmer than whatever lit up the Voorwerp, Schawinski and colleagues concluded. The quasar must have shut down sometime in the last 45,000 to 70,000 years, while its light was still traveling to the Voorwerp, and left the cloud as a ghostly echo of the dead quasar's former brilliance.

Because the quasar switched off so quickly, the accretion disk surrounding the black hole must have been relatively small, Done says. That's consistent with some models of how black holes gobble up their surroundings.

"Those models are quite hard to test," Done said. "This might tell us is that our ideas about accretion do actually work. I'm quite excited about it."

The quasar corpse also provides a unique laboratory for studying how galaxies evolve shortly after their central engines quiet down.

"It's certainly giving us a view of a very particular phase of the evolution of quasars, and one that we can't normally study," Done said.

The discovery would never have happened if not for Galaxy Zoo, Schawinski notes.

"We would have never found the nearest quasar to us, this system that will ultimately teach us so much about black holes and galaxies and how they evolve together, if it wasn't for citizen science and the internet," he said. "It's so much cooler than anything we could have imagined."

Image: WIYN/William Keel/Anna Manning

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High Oxygen Levels Spawn Monster Dragonflies

Posted: 02 Nov 2010 02:14 PM PDT

Biologists have grown super-size dragonflies that are 15 percent larger than normal by raising the insects, from start to finish, in chambers emulating Earth's oxygen conditions 300 million years ago.

The research, presented Nov. 1 at the Geophysical Society of America's annual meeting in Denver, Colorado, provides more support to the idea that big ancient animals and high-oxygen concentrations weren't coincidental. It may also offer an instrument to help gauge Earth's ancient atmospheric conditions.

"No one has been successful growing dragonflies under controlled laboratory conditions before, at least to my knowledge," said paleobiologist John VandenBrooks of Arizona State University, leader of the work. "This has allowed us to ask the question, 'how have oxygen levels through time influenced the evolution of insects?'"

During the Paleozoic era, around 300 million years ago, huge dragonflies zipped around with wingspans stretching more than two and a half feet, dwarfing modern relatives. Back then, however, the planet's atmosphere had roughly 50 percent more oxygen than today.

To explore the effects of ancient oxygen levels, VandenBrooks' team raised 11 other "living fossils," including beetles and cockroaches, in three habitats with different oxygen concentrations — one at the late Paleozoic's 31 percent oxygen level, another at today's 21 percent level and the third at 12 percent from 240 million years ago (Earth's lowest oxygen level since complex life exploded onto the scene half a billion years ago).

They found that dragonflies and beetles grew faster, as well as bigger, in a high-oxygen environment, while cockroaches grew slower and remained the same size. All but two bug species grew smaller than normal at low concentrations of oxygen.

Measurements of insect breathing-tube volume from the experiment could be correlated with that of insects trapped in amber, VandenBrooks said, providing a solid tool to determine oxygen levels in poorly understood eras.

"We started out with insect physiology to understand the fossil record better, in light of data from modern species," he said. "Then we realized we might have a biological tool to estimate ancient oxygen levels — a proxy — using that physiology in specimens trapped in amber."

 

Dragonflies are born as water-loving nymphs and spend about half a year wolfing down small worms, crustaceans and, eventually, larger prey such as guppy fish. When adults emerge as speedy terrestrial fliers, they begin breathing through a network of tracheal air tubes and live only for a couple of weeks.

"It wasn't quick, but it paid off," VandenBrooks said of raising the critters in the lab, adding that 225 nymphs (75 per atmospheric habitat) had to be hand-fed worms and guppies every day for almost half a year.

After the dragonflies and other bugs grew up, the researchers measured their breathing-tube volumes. They discovered that high oxygen concentrations lowered tracheal volume, while low oxygen concentrations boosted it. VandenBrooks said tracheal volume may directly affect dragonfly body size.

"As you become a larger insect, more of your body is taken up by tracheal tubes. Eventually you reach a limit to how big you can be," VandenBrooks said. "The more oxygen that is available, the smaller that system needs to be and the bigger you can grow."

Beetles also grew proportionally larger but, conversely, cockroaches didn't swell to monsters like dragonflies did in rich oxygen levels. Instead, they remained the same size and developed more slowly. Their tracheal volume, however, still decreased along with most of the other bugs.

"We're not sure why this happened, but we might be able to use tracheal volume in amber fossils to find out what oxygen concentrations were during some contentious periods in history," VandenBrooks said, noting oxygen levels around 300 million years ago are better known than from 120 to 65 million years ago, a period with "conflicting and poorly resolved" oxygen models.

"One model out there says levels were lower than now, another says higher-than-present levels," he said. "We need a good proxy to estimate historic conditions. Amber fossils are promising if we can more tightly correlate breathing-tube volume to oxygen."

VandenBrooks said he'd like to "take a more in-depth look at the fossil record and expand forward to the present and backward to the past" to see if amber is a viable proxy. In addition, he wants to repeat the oxygen-level experiment focusing more tightly on dragonfly behavior.

"We want to know how it affects their metabolism," VandenBrooks said. "How does it affect their ability to perform? Their speed? Their efficiency? I'd love to know these things."

Images: 1) Flickr/Al Power. 2) Micrograph of a modern honey bee's internal tracheal tubes, the means by which all insects exchange oxygen with their body's tissues./USDA 3) A dragonfly raised in one of VandenBrooks' hyperoxic habitats./John VandenBrooks.

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Arctic Lake Yields Planet’s Most Continuous Record of Ancient Climate

Posted: 02 Nov 2010 10:39 AM PDT

DENVER — It took the better part of a decade, $10 million, and help from the guys who build ice roads for Canadian truckers. But scientists now have the most continuous record of ancient climate ever extracted from the terrestrial Arctic.

What's more, the record — cored through sediment layers at the bottom of a lake in northeastern Siberia — also illuminates what happened when a big meteorite smashed into the spot 3.6 million years ago, when the ground was warmer and forested as opposed to the barren tundra it is today. Water filled the resulting crater and formed Lake El'gygytgyn (pronounced EL-gih-git-gin).

"We're really pleased that we have a complete record of that entire time period," said Julie Brigham-Grette, a geologist at the University of Massachusetts at Amherst and one of the project's leaders. She described the findings in Denver on October 31 at the annual meeting of the Geological Society of America.

Analysis of the lake cores is revealing details of how the Arctic landscape warmed and cooled over the past several million years, she said. Comparing similar data from the Arctic Ocean and Antarctica can show how the two polar regions — which are more sensitive to climate change than temperate or tropical latitudes — react differently to changing temperatures.

"The sheer logistics prevented anyone from doing this before," said Brigham-Grette.

 

Lake El'gygytgyn lies 100 kilometers north of the Arctic Circle and 360 kilometers from the nearest inhabited town: Pevek, Russia. The 12-kilometer-wide lake is too windy and rough to be drilled from a floating rig in the summer, so the researchers decided to drill in the winter from an ice platform.

To get there, the team had to ship camp materials and a drill rig to Pevek, then use helicopters or trucks running on an ice road that ended 90 kilometers short of the lake. For the final 90 kilometers equipment had to be hauled with bulldozers through the snow.

After all that, the team had to artificially thicken the lake ice by drilling a small hole and pumping water to the top to freeze again, to get the ice to the 2 meters of thickness that could support the weight of the drill rig.

The lake is deep enough to not freeze all the way to the bottom in winter, meaning it is a sediment trap whose layers of mud contain pollen and other indicators of what the environment was like at the time the material settled. Other lakes in the far north have frozen solid many times and thus don't contain such a detailed record.

This unique record along with the lake's high latitude make the work important scientifically, says Yarrow Axford, a paleoclimate expert at Northwestern University in Evanston, Ill., who is not involved in the project.

At the time the kilometer-wide meteorite hit, temperatures were probably 10 to 14 degrees Celsius warmer than today, Brigham-Grette said. The impact vaporized much of the silica-rich rock, turning it into a jumble known as breccia with fractured quartz grains and other particles melted by the impact's heat, said team member Christian Koeberl of the University of Vienna.

The core holds no tiny fossils or pollen in the 15 meters just above the layer that marks the meteorite impact, Brigham-Grette reported at the conference — possibly because the searing heat zapped anything that would otherwise have been preserved. At least ten different layers of volcanic debris, scattered throughout the core, reflect eruptions of volcanoes on the Kamchatka peninsula to the south, she said.

Brigham-Grette hopes to compare the cores to others from the same time period, like those drilled in Lake Baikal — also in Siberia but at 54 degrees north rather than 67 degrees — and others taken from the underwater Lomonosov Ridge in the Arctic Ocean.

Images: 1) Lake El'gygytgyn, as seen from space. Jesse Allen/NASA/GSFC/METI/ERSDAC/JAROS/ASTER. 2) Lake El'gygytgyn drilling camp in the high Arctic./NSF. 3) Drilling of the sediment core./NSF.

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Cutest Book Ever: ZooBorns Internet Craze Moves to Print

Posted: 02 Nov 2010 10:07 AM PDT

<< Previous | Next >>

Warning: The images in this gallery are dangerously, addictively cute. Once you have seen them, you'll want to see more, and more. And more. And you may never finish what you were working on before you saw them. But it's probably too late for you, anyway, because you've already seen the baby ocelot, so never mind.

If you weren't already aware of this thing called ZooBorns, then I'm sorry for doing this to you. Also, you're welcome, because it's the cutest thing ever on the internet.

And now you can't escape it, even when you are away from the internet, because the evil geniuses behind the ZooBorns website have just published two books of strangely, wonderfully, painfully cute baby zoo animals that you can take with you everywhere (I've already proven this with my review copies).

While you are waiting for yours to arrive, you can try to get by on the baby aardvark, gorilla, red pandas and more in this gallery, visit ZooBorns.com and hear what the authors, Andrew Bleiman and Chris Eastland had to say for themselves in the interview with Wired.com on the following pages.

Wired.com: Do you have a favorite ZooBorn?

Eastland: I'm your run-of-the-mill, crazy cat lady, just 30 years old and male. If I have to choose, it would probably be the Connecticut Beardsley Zoo's ocelot kitten, aka the Miracle Kitten (above). It got its name since it was only the third ocelot ever born via in vitro fertilization.

Above: Ocelot Kitten

Connecticut's Beardsley Zoo

Image: Shannon Calvert

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Baby Dolphin Survival Depends on Mom’s Friends

Posted: 02 Nov 2010 08:45 AM PDT

For dolphin mothers, successful parenting is as much a matter of having good friends as it is good genes.

The findings underscore the importance of community to dolphin life, and perhaps to animals in general — something that's intuitively appreciated, but hasn't been directly compared to genetic fitness in a wild mammal population.

Some studies, including research on captive chimpanzees, have linked heredity to the survival rates of young animals. Research on wild horses has connected offspring survival to maternal sociality. But researchers had not yet compared nature and nurture directly.

"In wild populations, genetic heritability and the social components of fitness have not yet been examined together," wrote researchers led by University of New South Wales biologists Celine Frère and William Sherwin in a paper published Nov. 1 in the Proceedings of the National Academies of Science.

 

For 25 years, the researchers have made detailed observations of bottlenose dolphins in the eastern gulf of Australia's Shark Bay. That one-of-a-kind dataset allowed them to chart the relatedness of dolphin moms and map their habits of social association, then correlate these patterns to how well their offspring survived childhood.

As would be expected, calves born to moms from reproductively successful families tended to do well. But for dolphin moms from less-fit families, that lack of a pedigree was offset if they tended to hang out with successful moms. The researchers' analysis suggested that keeping good company was just as important — even, at times, more important — than coming from good stock.

That society could have such importance isn't shocking: Dolphins are extremely intelligent, with complex communities and powers of communication that some researchers consider comparable to language. (It's also in Shark Bay that evidence of dolphin tool use was famously found.) Nevertheless, "we can only speculate" as to the details of how females help each other, wrote Sherwin in an e-mail.

Close friends might help protect female dolphins from unwanted male attention, reducing inbreeding and resulting health problems, wrote Sherwin. Defense could also be important, especially during birth and early nursing stages. "The dolphin population we studied is in Shark Bay," he wrote.

Image: Flickr, Steve Jurvetson.

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Citation: "Social and genetic interactions drive fitness variation in a free-living dolphin population." By Celine H. Frère, Michael Krützen, Janet Mann, Richard C. Connor, Lars Bejder, and William B. Sherwin. Proceedings of the National Academy of Sciences, Vol. 107 No. 44, November 1, 2010.

Brandon's Twitter stream, reportorial outtakes and citizen-funded White Nose Syndrome story; Wired Science on Twitter.
Posted by johnald

Tuesday, 2 November 2010

Johnald's Fantastical Daily Link Splurge

Johnald's Fantastical Daily Link Splurge

Hot Spot for Life Found on Ancient Mars Volcano

Posted: 01 Nov 2010 03:17 PM PDT

If life ever existed on Mars, then newly discovered mineral deposits on the flanks of a long-dead volcano would be a good place to dig for its remains.

Spotted by a high-powered orbital imager, they're not the first deposits found on Mars of silica, a mineral used by some simple forms of life, including single-celled algae that evolved early in Earth's volcanic past.

But the new deposits are the first from a locale with a definite volcanic pedigree, formerly rich in heat and water, as well as minerals — a locale formerly suited, by any earthly definition, for life.

Stand on the slopes of Nili Patera 3.7 billion years ago, and "you would see steam rising up out of the volcano. In the spots we see the deposits, that's where the highest concentration of steam would be," said geoscientist Jack Mustard of Brown University. "It'd be like standing on Hawaii, looking across a volcano, seeing the fumaroles where vapors are given off, or standing in Iceland where the hills are steaming."

 

Mustard's findings, co-authored with fellow Brown geoscientist J.R. Skok, were published October 31 in Nature Geoscience. His laboratory is among those that in recent years has processed an extraordinary flow of red planet data, returned by Mars-orbiting spacecraft and surface-exploring robots.

This data has moved researchers beyond looking for signs of water — the latest of which was reported just last week, by both the Spirit and Phoenix rovers — to evaluating potentially once-habitable environments in precise detail.

"It's the most definitive hydrothermal system we've found on Mars. You can see the source of the heat, the driving of the fluids that left the deposits," said Mustard. "In this deposit, you have the culprit right before you. In other deposits, they're either sedimentary, or in the center of an impact crater. You have no idea how they happened."

According to Mustard, traces of any organisms that existed could still be found in the silica, which is non-porous and ideal for preserving fossil remains from the ravages of time and weather. Even after 3.7 billion years, any degradation would come only from silica-penetrating cosmic rays, which break down biological compounds. Those would still leave telltale residues of carbon, and the ExoMars expedition robot, scheduled to launch in 2018, will be equipped with a six-foot-long drill perfect for digging beneath ray-damaged layers.

Mustard isn't yet prepared to say the rover Curiosity, successor to the Phoenix and Spirit rovers, should visit Nili Patera when it lands on Mars in 2012. Curiosity lacks ExoMars' planned drilling capacity, and already has a wealth of places to explore: the ancient lake deposits of Holden crater, a stack of sedimentary layers three miles thick in Gale crater, and the Mawrth Vallis river valley.

But Mustard couldn't help but speculate. "It would be pretty intriguing" if Curiosity found carbon amidst the silica, he said. "Or the rover, as it's going up the slopes, could dislodge some rocks and look underneath. That's where the good stuff is."

Images: The Nili Patera caldera./NASA, JPL-Caltech, MSSS, JHU-APL, Brown University.

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Citation: "Silica deposits in the Nili Patera caldera on the Syrtis Major volcanic complex on Mars." By J. R. Skok, J. F. Mustard, B. L. Ehlmann, R. E. Milliken and S. L. Murchie. Nature Geoscience, advance online publication, October 31, 2010.

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Giant Waves Solve Saturn Ring Mystery

Posted: 01 Nov 2010 11:57 AM PDT

Saturn's largest ring appears to behave like a mini spiral galaxy. NASA's Cassini spacecraft caught enormous waves sloshing back and forth across Saturn's B ring, similar to waves believed to give galaxies their spiral shapes.

"This is a major result," said Cassini imaging team leader Carolyn Porco of the Space Science Institute. "Saturn's rings are tiny tiny tiny compared to a galaxy, but we see the same physics."

The new observations also show two warped regions, including a tall arc of spiky peaks that rise almost two miles above the ring plane. These perturbations may have been sculpted by small moons that migrated across the ring disk, a process believed to be important in shaping planetary systems.

Saturn's most massive ring, the B ring, has baffled astronomers since the Voyager spacecraft flew by in 1980 and 1981. Those observations showed the B ring was sculpted into a flattened football shape with a sharp outer edge by the moon Mimas. But even in the Voyager images, it was clear the B ring was too complex and chaotic to be shaped by Mimas alone.

Now, in a new analysis published in the Astronomical Journal, thousands of Cassini images gathered over the course of four years have revealed three separate wave patterns that are not driven by any moons, but spring up spontaneously by drawing energy from the small, random motions of ring particles. The waves, which can be hundreds of miles long, keep themselves going by reflecting off the ring's edges.

 

"Think of it like waves in a pool," Porco said. If two kids are hopping up and down at either end of a pool, she says, the waves they send sloshing across the water will pass through each other and reflect off the edge of the pool.

In Saturn's rings, the waves are more like compressions in a Slinky than water waves, but the physics is similar. "These waves just go back and forth, and keep reflecting until they finally grow large enough so that we can actually see them," Porco said.

"Normally viscosity, or resistance to flow, damps waves — the way sound waves traveling through the air would die out," said planetary ring expert Peter Goldreich of Caltech and the Institute for Advanced Study in Princeton, who was not involved in the new study, in a press release. "But the new findings show that, in the densest parts of Saturn's rings, viscosity actually amplifies waves, explaining mysterious grooves first seen in images taken by the Voyager spacecraft."

Cassini has also observed similar waves on smaller scales, with wavelengths around 300 feet. Computer models of galaxies and protoplanetary disks around other stars have shown similar randomly generated waves with proportionally larger wavelengths. But because those waves would take hundreds of millions of years to complete one slosh, astronomers can't observe them directly.

"This is the first time we've seen these things in nature," Porco said. "It underscores the deep, physical connection between what we're studying at Saturn's rings, and disk systems across the universe at a very large range of spatial scales."

Cassini has also snapped pictures of sharp, stalagmite-like peaks at the edge of the B ring that made themselves known by throwing long spiky shadows (below).

The new study suggests this region of the rings contains small moons that compress the ring material like a soda can and force it upward. This idea is supported by the presence of at least one moonlet, caught during Saturn's summer equinox when it cast a shadow across the rings.

These moonlets may have migrated across Saturn's rings, and become trapped in a gravitational resonance with the larger moon Mimas. This process of migration and trapping is exactly how scientists believe the solar system achieved its current architecture.

In this way, Saturn serves as a nearby laboratory to study celestial structures on all scales, from planets to solar systems to galaxies.

"There are basically two shapes in the universe, there's disks and there's spheres," Porco said. "Saturn's rings allow us to understand one of the two main structures in the universe: a celestial disk system."

"This is not just a slight addition, it's something significantly new," Goldreich told Wired.com. Goldreich and colleagues predicted the presence of these waves in 1985, but the Cassini observations provide the first proof.

"A lot of times, you don't expect to be around to see whether you made a prediction that worked," Goldreich said. "I was quite pleased to see it."

Video and Image: NASA/JPL/Space Science Institute

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Video: Climate Model Suggests Where the Aliens Are

Posted: 01 Nov 2010 10:36 AM PDT

The jury is still out on whether nearby red dwarf star Gliese 581 hosts a planet in its habitable zone, as astronomers announced last month. But the controversy hasn't stopped the planet's co-discoverer from speculating about where the aliens are in a new study that lays out the first model of what the planet's atmosphere might look like.

The potentially habitable world, called Gliese 581g, is about three times the mass of Earth and orbits its star once every 36.6 Earth days, reported astronomer Steve Vogt of the University of California, Santa Cruz. That orbit plants it close enough to the star that it ought to be tidally locked, showing the same face to the star at all times.

This setup would likely leave one hemisphere a scorching desert and the other a frigid ice sheet. With the right amount of global warming, either or both sides could conceivably be habitable. But the most comfortable place for life to grab a toehold would probably be in the zone of permanent twilight, where the sun is always rising or setting.

Or so Vogt assumed. In a new paper submitted to the Monthly Notices of the Royal Astronomical Society, Vogt and atmosphere-modeling expert Kevin Heng of The Swiss Federal Institute of Technology Zurich find that the planet's most comfy spots probably lie along a sideways V-shaped curve, with two eddies of warmth at the tips.

"What we're finding basically is that the patterns of warmth and cold on these things is a little more complicated," Vogt said. "In fact, the most comfortable place is probably around the chevron, in the vortices."

 

The still-unconfirmed planet was detected through subtle gravitational tugs on its parent star, which had to be teased apart from the conflicting signals of five sibling planets that range from about two to 15 times the mass of Earth.

This planet-hunting method gives no data on what the planet looks like, however. Future telescopes may be able to snap fuzzy pictures of Gliese 581's planetary family. But until then, the alien atmospheres are up in the air.

To bring Gliese 581g's possible climate down to Earth, Vogt and Heng modified a simplified climate model often used to simulate Earth. In recent years, Heng and others have started using the modeling package to simulate atmospheres on gas giant exoplanets.

"As soon as I heard about this, I thought, let's turn it loose on Gliese 581g and tell me where the aliens are living," Vogt said.

The researchers scaled the model's temperature parameters to reflect the heat Gliese 581g would absorb from its parent star, which is dimmer but closer than ours. They set the temperature at the equator to about 40 degrees Fahrenheit, and assumed the temperature difference between the equator and the poles was similar to Earth's, about 60 degrees. The team also assumed certain properties of the atmosphere, like the amount of heat it can absorb and the surface pressure, were just like Earth's.

The team ran the model for 1,000 Earth days to see what long-term weather patterns showed up. They found a constant light wind, like a slow jet stream, developed around the planet, pulling warm air into a V-shape. That whole V would probably be habitable, Vogt suggests. Extra whorls of warmth in the north and south "might be nice vacationing spots," he said.

"It's a great start for understanding the patterns of flow on these super-Earth exoplanets," said exoplanet expert Sara Seager, who was not involved in the new study. "It's pretty cool that even under all these approximations and assumptions, he always finds spots that are habitable. That's reassuring."

But don't pack your bags yet. A separate group of astronomers announced Oct. 12 that the planet might not be there at all, and could just be a trick of the data.

"Personally, I have to admit that this debate on habitability seems a lot less relevant if Gliese 581g doesn't actually exist," said astronomer Heather Knutson of the University of California, Berkeley, who models the atmospheres of hot gas giant exoplanets. "Given all of the other transiting planets currently being discovered by the Kepler mission, I think we'll probably have an actual, confirmed planet in the habitable zone … in the next one to two years."

Vogt is undeterred. "Whether or not Gliese 581g is confirmed, there's going to be others like this," he said. "'What is life like there?' is becoming an interesting field in its own right. We have enough computing power now to make some interesting conclusions about where things might live."

Video: Heng & Vogt/MNRAS. Image: Heng & Vogt/MNRAS.

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