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Permalink Reply by archaeopteryx on July 1, 2012 at 9:12pm

I did not know that, thanks for the update - while on the page, I also learned how to double-check my Mac for Trojans, all clean!

Permalink Reply by doone on July 1, 2012 at 7:13pm

How Anteaters Decide What To Eat

By Jason G. Goldman | June 28, 2012 |  

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The Giant Anteater, Myrmecophaga tridactyla, only eats ants and termites, as its name suggests. Since the giant anteater and its evolutionary ancestors have been feasting on ants and termites for nearly 60 million years, a researcher named Kent Redford hypothesized that, over time, ants and termites may have evolved various defenses to avoid predation. In other words, there may have been a co-evolution between the feeding preferences of anteaters and the defenses of their prey. To investigate this question, in 1984, Redford went to Brazil to study a group of anteaters at the Brasilia Zoo, as well as in the wild at Emas National Park.

Ants and termites are highly social critters, and their social structure consists of three main groups: the reproductive, the worker, and the soldier castes. The defenses of the soldier castes in termites and ants vary from entirely chemically based, in which they secrete toxic or repellent chemicals, to the fully mechanical, in which they use their mandibles to pierce the skin of the attacker, and occasionally to draw blood. Redford hypothesized that the foraging behavior of the anteaters would vary according to the type of defense behavior employed by the soldier castes of the ant and termite colonies on which they fed.

The first part of the study was conducted with the help of three giant anteaters that were kept at the Brasilia Zoo. Two shallow trays were placed before the anteaters, each of which contained broken up pieces of a termite mound. Each tray, therefore, contained thousands of living and active termites, of one of eight possible species:Grigiotermes metoecus, Armitermes euamignathus, Cornitermes cumulans, Cortaritermes silvestri, Nasutitermes, Procorniterrnes araujoi, Velocitermes paucipilis, and Orthognathotermes gibberorum. Each individual anteater was tested with all possible two-way combinations to determine their overall preferences.

The researchers recorded the sequence in which the individuals ate the different species, as well as the number of times the anteater sniffed but did not snack on a particular species. Since it was impossible to quantify the number of termites eaten, they recorded the duration of each feeding session as well, for each termite species. The anteaters’ foraging behaviors were compared with three termite variables: the size of the termites, their nutritional value, and the type of defensive system that they used (chemical or mechanical).

The anteaters did not feed on the different species equally. In 24 of the 28 two-way comparisons, there were clear preferences for one termite species over the other, and all three individual anteaters showed the same preferences. The two tastiest termite species were Cornitermes and Procornitermes.

Salvidor Dali walks his pet anteater. (Unknown source)

These findings alone suggest that the anteaters are making explicit foraging decisions, instead of opportunistically dining on whatever critters are around. Redford wanted to know, however, how do the anteaters decide which species to eat? How do anteaters make their decisions?

Prey size did not correlate significantly with feeding decisions, nor did the nutritional value of the prey. Both of those possibilities were easily ruled out. The percentage of the colony that comprised the soldier caste was not correlated with feeding decisions, either. Nor was the aggressiveness of the termite soldiers. Despite their clear preferences, Redford was unable to determine the variables that were behind those preferences.

Perhaps wild anteaters could provide some clues.

Redford and his colleagues drove around the national park, searching for anteaters. Once they spotted an anteater, they’d get out of the car and follow on foot. Data was collected on the location and duration of feedings, as well as (where possible) the prey species. The anteaters spent 23.1% of their time (across 40 observations and 1487 individual feeding sessions) engaged in feeding behaviors. Eight species of termites and six species of ants were identified across the observed feeding sessions.

Again, it was clear that the anteaters displayed clear preferences. But the preferences shown by the wild anteaters were different from the preferences shown by their captive cousins. For example, the favorite termite species of the captive anteaters,Cornitermes, accounted for only 12% of the feeding time in the wild and was rated only fourth in preference. And the least favorite genus of the captive anteaters,Velocitermes, was the favorite in the wild.

What can explain the differences in terms of species preference? One possibility is the mound structure that the different species use. In the tests at the zoo, the anteaters never had to break into a termite mound; instead, the crumbled up mound pieces were presented to them. For example, Syntermes, one of the favorites in the zoo, has a mound structure that goes up to 1.5 meters into the ground, allowing the ants to retreat into deeper ground when attacked from above. It is also possible that certain defenses (particularly, the chemical defenses) may have been significantly less effective in the broken-up mounds offered to the captive anteaters.

Additionally, in the wild, the anteaters may feed in such a way as to avoid the soldiers, and face a lower soldier-to-worker ratio than in the samples offered in the zoo. Specifically, at the beginning of an anteater feed, more workers and fewer soldiers are present than is the case after even a few seconds. Previous studies have shown that once the ratio of soldiers-to-workers becomes unfavorable (due to the retreat of workers and the recruitment of soldiers), anteaters will take a break from eating. Scientists had already known that this was the case by determining the soldier-to-worker ratio in anteater stomach samples.

Another possible explanation for the discrepancy is that, in many cases, multiple species of termites or ants share the same mound. This may mean that certain species that were particularly palatable under the controlled environment at the zoo, were less favorable in the wild due to their proximity to other less desirable or more aggressive species.

Yet another explanation for the discrepancy comes from the possibility that anteaters may be not specialized for ants or termites, per se, but rather on small arthropods that live socially. In Venezuela, anteaters prey mostly on ants, while in Brazil, they feed mostly on termites. The diet differences are probably related to differences in the relative availability of various species of ants and termites in the different regions. Thus, Redford argues:

Anteater preference may be only relative to the social insects available to them and not based on factors intrinsic to particular prey species. This flexibility would be necessary to allow [anteaters] to range through so many different habitats with their different social insect communities, and may account for the lack of agreement between wild and captive preferences reported in this study.

Very likely, each of these possibilities probably plays a role in explaining the observed discrepancies in prey preferences between the captive and wild anteaters.

What about the larger issue of defense strategy? When combining data from both the captive experiments and the wild observations, Redford discovered that the anteaters tended to avoid termites that used chemical defenses, in favor of those that relied on mechanical defenses. It may be that the species (such as Procornitermes andCornitermes) that rely on using their mandibles to slash or slice tend to be effective defenses for small predators (like mice), but are generally ineffective against larger predators such as anteaters that slurp them up with their long saliva-covered tongues.

Redford made one other important observation. Giant anteaters feed on all of the different prey species in a similar way, irrespective of nutritional value, mound structure, or defense system: they feed for short periods of time, switching frequently from mound to mound. It had been previously suggested that this was simply prudent predation: the anteaters could avoid totally destroying any particular mound and losing a valuable source of food. Instead, these data suggest that the anteaters’ predatory patterns emerge because of the defensive strategies employed by their prey. Once there are too many soldiers around, it becomes time for the anteater to move on to the next mound.

While predators improve their hunting-related behaviors, the prey improve their ability to avoid predation and escape from their predators. This game of evolutionary ping-pong, played out over millions of years, has resulted in an elaborate set of defenses in ants and termites, and an equally sophisticated set of hunting techniques in anteaters. As long as both teams are playing, neither team will win.

Kent H. Redford (1985). Feeding and food preference in captive and wild Giant anteaters (Myrmecophaga tridactyla) Journal of Zoology, 205, 559-572.

Permalink Reply by doone on July 1, 2012 at 7:25pm

Permalink Reply by doone on July 2, 2012 at 6:28am

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NASA Maps Heat Wave Fueling Wildfires in the Rockies

On June 28, 2012, wildfires raged across the western United States. The Waldo Canyon fire in Colorado attracted the most attention after spreading into Colorado Springs and charring hundreds of homes, but large wildfires also burned throughout Utah, Wyoming, Montana, New Mexico, and Arizona.

A lack of winter snow cover and ongoing drought primed vegetation in these states for ignition. But in recent weeks, another ingredient for extreme wildfire emerged: heat. High temperatures dry out vegetation and decrease the relative humidity, making it easier for fires to ignite and spread.

The intensity and scope of the heat wave in the western United States is visible in this map of land surface temperature anomalies for June 17–24, 2012. Based on data from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite, the map depicts temperatures compared to the 2000–2011 average for the same eight day period in June.

Areas with warmer than average temperatures are shown in red; near-normal temperatures are white; and areas that were cooler than the 2000-2011 base period are blue. Colorado experienced the brunt of the heat wave and had eight large wildfires burning on June 28, 2012. Wyoming and Utah—other states that have seen unusually hot weather—together had nine wildfires burning.

Land surface temperatures (LST) are distinct from the air temperatures that meteorological stations typically measure. LSTs indicate how hot the surface of the Earth would feel to the touch. From a satellite vantage point, the “surface” includes a number of materials that capture and retain heat, such as desert sand, the dark roof of a building, or the pavement of a road. As a result, daytime land surface temperatures are usually higher than air temperatures.

This heat wave, like all extreme weather events, has its direct cause in a complex set of atmospheric conditions that produce short-term weather. However, weather occurs within the broader context of the climate, and there’s a high level of agreement among scientists that global warming has made it more likely that heat waves of this magnitude will occur.

NASA Earth Observatory image by Jesse Allen, using MODIS data provided by Land Processes Distributed Active Archive Center (LPDAAC). Caption by Adam Voiland

http://www.nasa.gov/mission_pages/fires/main/usa/20120629-westernUS...

Permalink Reply by doone on July 3, 2012 at 5:40pm

LADIES AND GENTLEMEN, THE HIGGS BOSON HAS BEEN FOUND!

I know that I should probably not be doing this but I am too excited not to: I have it onvery good authority from a prominent experimental physicist in the middle of the action that CERN will indeed be announcing the discovery of the Higgs Boson tomorrow in Geneva. Here is how my "Deep Throat" contact puts it:

It's 5 sigma more or less, and I am sure there will be some debate about the semantics of calling it a "discovery" or not but more or less it is a discovery...it's there! Probably the most boring and exciting moment in physics...

How confident am I in my confidant? Let's put it this way: if this turns out to be a "Dewey Defeats Truman" moment for 3QD, I will take on the responsibility of personally assassinating my source! :-) And, yes, I have permission from her/him to post this.

We will have much more about all this tomorrow I am sure. What an exciting moment!

Posted by Abbas Raza at 03:59 PM | Permalink

Permalink Reply by Michel on July 3, 2012 at 6:17pm

I want to see what Phil Plait has to say about this tomorrow.
For now it's a huge hypefest.

Permalink Reply by doone on July 3, 2012 at 7:19pm

Image credit: Hitchhiker's Guide to the Galaxy.

They’re very likely going to announce that the 5-σ threshold, the “gold standard” for discovery, has been reached, and that we’ve discovered the Higgs boson. The only question is whether CMS and/or ATLAS will have enough proverbial coin-flips to announce a discovery on their own (there’s a reason it’s taken this long), or whether they’ll need to combine results to reach that pinnacle. (My money’s on the former, which is more convincing, but we’ll have to wait and see.)

http://scienceblogs.com/startswithabang/2012/07/03/the-biggest-fire...

Permalink Reply by doone on July 4, 2012 at 7:56am

Browse more infographics.

Permalink Reply by doone on July 4, 2012 at 7:58am

Permalink Reply by Hope on July 4, 2012 at 11:47am

 

Higgs boson discovery leads to FDA-approved 'mass reduction' weight loss therapy  (satire)

(NaturalNews) The extraordinary discovery of the Higgs boson particle, long  sought after in the physics community to help explain the "Standard Model" of  physical reality, took the world by storm today. Achieving a 5-sigma level of  statistical significance, the supercollider data show with almost complete  certainty that the Higgs boson -- the "God particle" -- really exists. But the  question remains: What use is it?
Aside from the fact that without the  Higgs field, the cosmos as we know it would cease to function, the far more  important application in a culture largely devoid of scientific education is weight loss. Fortunately, scientists at CERN have already found a way to  turn this multi-billion-dollar experiment into a medical weight loss  breakthrough, which is of course far more important than understanding the  origins of the universe.
"The Higgs particle is responsible for all  mass," explained CERN scientist Dr. Larry Chekov. "By stripping Higgs particles  from a given human specimen, we can make human beings massless."

First you get really heavy, and then you hit the wall

Call it "the  ultimate weight loss," if you wish. After this treatment -- soon to be offered  inside the Large Hadron Collider itself -- patients will emerge as human beings without mass. "You will weigh exactly nothing," Dr. Chekov  explained.
The Higgs Weight Loss Treatment, as it is now being billed,  involves being stuffed into the Large Hadron Collider and accelerated to  99.99999999% the speed of light, which may cause nausea in some people,  according to the FDA. At this speed, the average person's body initially takes  on enormous mass, causing them to become extremely obese. This obesity is only  momentary, however, as their body is almost instantly smashed against a blunt  surface that causes the atomic components of their body's cells to splatter in  all directions. A team of physics department interns then painstakingly plucks  all the Higgs particles out of the air using entangled pairs of microscopic  chopsticks, just before the body slams back together in its new, massless  configuration, ready for primetime television.
"It's relatively  painless," explained Chekov, "generally relativistically speaking."

What it all means, really

Scientists are expected to start Hawking the  procedure as a new Greene technology to help people avoid becoming Bohred with  their bodies. If people are tired of their Heaviside from reaching their body  weight Max, well they can now do something about it, at least Fara day if not  for a lifetime.
Dr. Senberg, the medical operations officer for the new  procedure, greets everybody with a courteous hello, to which his assistants  respond, "Hi, Senberg," but always with a sense of  uncertainty.
Enhancements to body shape and size may also be possible  with the Higgs Weight Loss Therapy, including sexual enhancements for men to  give them bigger and stronger Boltzmanns. For women, saggy butts can be made  more Fermi.
Convincing the initial test subjects to undergo the procedure  was a challenge, everyone admits. "We wanted to test men, and then release men,"  explained one of the assistants, "but first we had to Feynman who were willing  to participate, and that wasn't easy."
"Don't Teller," quipped Dr.  Senberg, "but we already found Watt we want. He's a Young guy, a real Joule, and  he swears the procedure never Hertz."
Some patients emerge from the  procedure with a Planck stare and a sense of being belittled by "Ler" the lab  assistant, but when Dr. Senberg tried to give Ler away, she wouldn't leave his  general orbit so he just Kepler around because of her consistent motion. She was  good at Hubbling, it turns out.

Strange side effects may appear

The FDA says it may require scientists  to warn people about the side effects of having no mass. They include slowly  drifting away from the planet's surface and out of the sun's orbit, an inability  to play kickball without being toppled over by the ball, and ejecting yourself  into the bathroom ceiling from passing gas on the toilet.

None of these  are considered a barrier to FDA approval, however, since the FDA approves  anything as long as there is scientific proof that it will make  money.
For more information about the Large Hadron Collider and the  upcoming Higgs Weight Loss Therapy which removes all mass from the abdominal  region (and thighs, too, for an extra fee), visit the LHC website at:

http://public.web.cern.ch/public/

Editor's note:  This satire article is meant in good fun. We admire the physicists at the LHC  and appreciate their significant contributions to the world of knowledge. The  confirmation of the Higgs boson is a true milestone in the history of science.  Now if they would only start searching for the "consciousness particle," things  would get even more interesting, eh?

Learn more:  http://www.naturalnews.com/036374_Higgs_boson_God_particle_weight_l...

Permalink Reply by archaeopteryx on July 4, 2012 at 12:37pm

Priceless, Hope! I raise my einstein of beer to you --

Permalink Reply by Michel on July 4, 2012 at 12:39pm

Higgs Boson - the object:

Higgs boson-like particle discovery claimed at LHC

COMMENTS (1252)

By Paul RinconScience editor, BBC News website, Geneva

Cern scientists reporting from the Large Hadron Collider (LHC) have claimed the discovery of a new particle consistent with the Higgs boson.

The particle has been the subject of a 45-year hunt to explain how matter attains its mass.

Both of the Higgs boson-hunting experiments at the LHC see a level of certainty in their data worthy of a "discovery".

More work will be needed to be certain that what they see is a Higgs, however.

Prof Stephen Hawking tells the BBC's Pallab Ghosh the discovery has cost him $100

The results announced at Cern (European Organization for Nuclear Research), home of the LHC in Geneva, were met with loud applause and cheering.

Prof Peter Higgs, after whom the particle is named, wiped a tear from his eye as the teams finished their presentations in the Cern auditorium.

"I would like to add my congratulations to everyone involved in this achievement," he added later.

"It's really an incredible thing that it's happened in my lifetime."

Prof Stephen Hawking joined in with an opinion on a topic often discussed in hushed tones.

"This is an important result and should earn Peter Higgs the Nobel Prize," he told BBC News.

"But it is a pity in a way because the great advances in physics have come from experiments that gave results we didn't expect."

'Dramatic'

The CMS team claimed they had seen a "bump" in their data corresponding to a particle weighing in at 125.3 gigaelectronvolts (GeV) - about 133 times heavier than the protons that lie at the heart of every atom.

They claimed that by combining two data sets, they had attained a confidence level just at the "five-sigma" point - about a one-in-3.5 million chance that the signal they see would appear if there were no Higgs particle.

However, a full combination of the CMS data brings that number just back to 4.9 sigma - a one-in-two million chance.

Prof Joe Incandela, spokesman for the CMS, was unequivocal: "The results are preliminary but the five-sigma signal at around 125 GeV we're seeing is dramatic. This is indeed a new particle," he told the Geneva meeting.

Atlas results were even more promising, at a slightly higher mass: "We observe in our data clear signs of a new particle, at the level of five sigma, in the mass region around 126 GeV," said Dr Fabiola Gianotti, spokeswoman for the Atlas experiment at the LHC.

Prof Rolf Heuer, director-general of Cern, commented: "As a layman I would now say I think we have it."

"We have a discovery - we have observed a new particle consistent with a Higgs boson. But which one? That remains open.

"It is a historic milestone but it is only the beginning."

Commenting on the emotions of the scientists involved in the discovery, Prof Incandela said: "It didn't really hit me emotionally until today because we have to be so focussed… but I'm super-proud."

Dr Gianotti echoed his thoughts, adding: "The last few days have been extremely intense, full of work, lots of emotions."

A confirmation that this is the Higgs boson would be one of the biggest scientific discoveries of the century; the hunt for the Higgs has been compared by some physicists to the Apollo programme that reached the Moon in the 1960s.

The rest on BBC News

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