Tuesday, 8 March 2011

Johnald's Fantastical Daily Link Splurge

Johnald's Fantastical Daily Link Splurge

Video: Elephants Lend a Helping Trunk, Pass Cooperation Test

Posted: 07 Mar 2011 02:10 PM PST

Asian elephants have passed a test of cooperation with flying colors, one that cognitive psychologists say demonstrates an ape-level awareness and sense of teamwork. Their collaboration isn't just the product of rote learning, but the result of careful thought.

In the wild, of course, elephants routinely work together. But that doesn't pass laboratory muster, said University of Cambridge psychologist Joshua Plotkin.

"It's anecdotal evidence. These animals are empathetic, they're cooperative. But how empathetic? How cooperative?" he said. "The best we can do is institute controls, do experiments like this, and figure out how what they do is unique from learning."

Plotnik's experiment, published March 8 in the Proceedings of the National Academy of Sciences, was conducted when he was a student of famed Emory University ethologist Frans de Waal. In 2006, they showed that elephants could recognize themselves in a mirror, a benchmark feat believed to indicate an especially sophisticated level of self-awareness, on par with that of young humans.

Though important, mirror self-recognition is just one test, and doesn't address the sort of cooperative behavior for which elephants are famed in the wild. They're known to help individuals in distress, cooperate in rearing children, and may even mourn their dead. From a behavioral perspective, they clearly demonstrate empathy.


But behavioral records from the wild are not the currency of cognitive psychology. After all, bees display incredible coordination, but few people would compare an individual bee's consciousness to that of a person. According to Plotnik, it could be argued that elephants and other cooperative animals are acting reflexively rather than thoughtfully. So he and de Waal turned to a test originally developed to measure cooperation in chimpanzees.

In the original test, two chimps pulled on ropes attached to an otherwise inaccessible, food-containing box too heavy for one alone to move. In the version updated for elephantine strength — a too-heavy box would have been "as big as a 747," said Plotnik — the rope was arranged so that if one elephant pulled alone, its partner couldn't reach the rope. To get a banana treat, both had to pull simultaneously.

Plotniks' elephants pick the trick up quickly. Then, in the study's key step, they demonstrated patience. If only one elephant was present, it would wait for a partner to arrive. Until then, it wouldn't try to pull the rope, and often wouldn't pick it up.

If the elephants pulled automatically, it would be evidence of reflexive behavior, said Plotnik. Waiting indicated something more. They understood that their own effort wasn't enough. They understood their partner's role. (One elephant, seen in the video below, even figured out how to cheat. By standing on her end of the rope rather than pulling, her partner had to do all the work — not very nice, perhaps, but smart.)

Plotnik's now working on other, more sophisticated tests of elephant cooperation. He hopes to measure how they see other species, process information in the wild, find food and water, and care for one another. But he acknowledges that Asian elephants are unique among social, cooperative animals in their amenability to study. Other animals — say, lions — may be just as smart, but not so easy to test.

"Just because something hasn't been tested doesn't mean you reject it as not being possible," he said.

Video: 1) Two Asian elephants help each other pull closer a table bearing banana treats./Joshua Plotnik, University of Cambridge. 2) An especially clever Asian elephant named Neua Un figures out how to make her partner do all the work./Joshua Plotnik, University of Cambridge.

See Also:

Citation: "Elephants know when they need a helping trunk in a cooperative task." By Joshua M. Plotnik, Richard Lair, Wirot Suphachoksahakun, and Frans B. M. de Waal. Proceedings of the National Academy of Sciences, Vol. 108 No. 10, March 8, 2011.

Alien Microbe Claim Starts Fight Over Meteorite

Posted: 07 Mar 2011 01:53 PM PST

NASA astrobiologist Richard Hoover thinks he's found fossilized alien bacteria inside a meteorite. If he's right, it's world-shaking news. But that's a very, very big if.

"There are legitimate reasons to initially be skeptical of these findings," wrote University of Oklahoma geophysicist Michael Engel in a commentary published March 7 by the Journal of Cosmology, where Hoover's claims were announced on March 4. Nevertheless, "I encourage people to keep an open mind when forming an opinion as to the significance of this work."

Hoover's claims involves carbonaceous chondrites, a class of rare meteorite that formed early in the solar system's history and contain organic chemicals, ostensibly picked up on their passage through space.

When those chemicals are found on Earth, they're considered signs of life. When found in a meteorite, their origin is intriguing but undetermined — a likely sign of contamination by Earthly chemicals or microbes, but hypothetically evidence of extraterrestrial life.

According to Hoover, he hasn't just found suggestive chemical traces, but complex filament-like structures that could only come from bacteria. Because there's no nitrogen in the meteorites, and Earthly microbes always contain nitrogen, he concludes that these fossils must come from life that evolved elsewhere.

"This finding has direct implications to the distribution of life in the Cosmos," wrote Hoover, with great understatement.


The claims have already set off an internet tempest of commentary, some of it noting Hoover's fringe announcement venue. The Journal of Cosmology is non-peer reviewed. It's also produced by a community of astrobiologists who are zealously evangelical about galactic panspermia, or the notion that Earth was seeded by life arriving from space.

Fifty years ago, that notion was crackpot. Nowadays, it's rather more plausible, if not so certain as some proponents insist. Life's building blocks have been found in comets, which could serve as spacefaring petri dishes. There are likely billions of Earth-like planets just in the fraction of space visible to the Hubble telescope. Given trillions of years and billions of opportunities, other examples of self-replicating chemicals don't seem improbable.

"I see no convincing evidence that these particles are of biological origin."

Beyond the venue, however, critiques of Hoover's claims become more substantive. "As a microbiologist who has looked at thousands of microbes through a microscope, and done some of my own electron microscopy, I see no convincing evidence that these particles are of biological origin," wrote SETI Institute astrobiologist Rocco Mancinelli in an email to Wired.com.

"The main claim of similarity with modern earthly analogues is totally inadequate," said University of Croatia microbiologist Stjepko Golubic, who specializes in the sort of bacteria to which Hoover compared the alleged fossil remains. "It is important to note that the SEM" — scanning electron microscope, used in this study — "is an inadequate tool for identifying cyanobacteria and this includes those images offered in this paper for comparison."

Mancinelli also criticized Hoover's sterilization techniques, which were not fully described in the paper. "It is unclear to me if the techniques used for the analyses were adequate. For example, the paper states that the implements used were flame sterilized. Does that mean they were placed in a Bunsen burner where soot" — which could confound the results — "could get on them?" Mancinelli wrote.

NASA astrobiologist Chris McKay defended Hoover's practices, saying he is "a careful and accomplished microscopist so there is every reason to believe that the structures he sees are present and are not due to contamination."

"If these structures had been reported from sediments from a lake bottom there would be no question that they were classified correctly as biological remains."

"If these structures had been reported from sediments from a lake bottom there would be no question that they were classified correctly as biological remains," wrote McKay. (Note: Though they share a surname, it was NASA astrobiologist David McKay who lead a team that in 1996 reported evidence of Martian microbes in a meteorite. That claim remains inconclusive.)

Nevertheless, the structures could conceivably be random. They could also just be fossilized bugs from Earth, said Allan Treiman, planetary petrologist at the Lunar and Planetary Institute in Houston.

"The meteorites Dr. Hoover studied are rich in carbon compounds that formed off of the Earth. However, Earth microbes do not know the difference, will eat alien carbon with gusto," he said. "Because all of these meteorites have been on the Earth for many years, and have not been kept isolated from Earth microbes, it's certain that they have been exposed to Earth microbes."

Yet Engel is less willing to draw conclusions. Independent experts need to analyze Hoover's images, and it would be useful if there were better grounds for comparison than visual similarity with known bacteria, he wrote.

According to Engel, his own analyses of a meteorite analyzed by Hoover found no evidence of common amino acids, suggesting that Earthly microbes had not invaded them.

"Faced with the actual possibility of evidence for extraterrestrial life, we quite often feel more compelled to ignore it or refute it rather than embrace it," wrote Engel. "Perhaps this has something to do with our inherent fear of the unknown."

SETI research director Jill Tarter compared Hoover's findings to the controversial recent discovery of extremophile bacteria that may metabolize arsenic, something never before seen on Earth and suggestive of how extraterrestrial bugs could survive in supposedly inhospitable environments.

Like that claim, Hoover's "may turn out to be correct, but it has not yet been proven," said Tarter. "Incredible claim; incredible evidence, not so much."

Dave Mosher contributed to this report.

Image: Journal of Cosmology

See Also:

Citation: "Fossils of Cyanobacteria in CI1 Carbonaceous Meteorites." By Richard B. Hoover. Journal of Cosmology, March 2011.

Sleep Quality May Be Tied to Covert Brain Wave

Posted: 07 Mar 2011 06:57 AM PST

Making waves isn't conducive to staying asleep, at least when the waves are a type of brain signal associated with being awake.

A type of brain activity known as an alpha wave emanates from the back of the head when a person is awake but relaxing with eyes closed. Scientists used to think that the wave was subdued and disappeared as a person fell deeper and deeper into sleep.

But the alpha wave doesn't disappear; it just goes undercover during sleep, researchers report online March 3 in PLoS One. The covert alpha wave may help determine how deeply people sleep and how much noise is needed to rouse a sleeper.

The finding "stresses that sleep is really a dynamic process," says Mathias Basner, a sleep researcher at the University of Pennsylvania in Philadelphia who was not involved in the study. The study shows that sleep doesn't happen just in discrete blocks, as most charts of sleep stages would indicate. Instead, brain activity changes from moment to moment during sleep.

"It may suggest that something is going on in the central nervous system that we don't know about and should maybe pay more attention to," Basner says.


Scientists hadn't ignored alpha waves on purpose, says study coauthor Scott McKinney, a sleep scientist at Massachusetts General Hospital and Harvard University. Researchers typically measure brain activity during sleep with electroencephalographs, or EEGs, devices that use electrodes on the scalp to detect electrical activity in the brain. The squiggly lines recorded by the EEG can be hard to interpret with the naked eye, so McKinney and his colleagues used computer programs to break the EEG signals from 13 volunteers down into discrete waves. The analysis revealed that alpha waves never truly go away; they just get drowned out by more vigorous signals the way spreading ripples from a small rock dropped in a pond are swamped by waves from a passing speedboat.

Alpha wave activity decreases as people enter ever-deeper levels of sleep and increases as people cycle back into more shallow sleep stages. In study participants, the ups and downs of alpha wave activity were closely associated with how easily a person could be awoken by traffic noises, loud talking or other sounds that might be encountered in hospital or at home in a city. When alpha wave activity spiked just before a noise was played, volunteers woke up more easily than when alpha wave activity was low, the researchers found.

Alpha wave activity may be the brain's way of keeping people aware of their surroundings during sleep, speculates Phyllis Zee, director of the Sleep Disorders Program at Northwestern University in Chicago. Such awareness enables people to wake quickly in case of danger, but too much alpha activity might also have a downside if it prevents a good night of sleep.

People with insomnia commonly complain that they are very light sleepers and are always aware of their surroundings, Zee says. Although many insomniacs get a full night of sleep, they report that their sleep is not restful. But laboratory tests often don't show any abnormalities.

"The classical way we're scoring sleep may not give a good handle on what a patient really experiences," she says. "This new way of analyzing depth of sleep may be used to get a better understanding of a patient's complaint."

Image: cobalt123/Flickr

See Also: