Too Much Dark Matter in Galaxy Cluster? 'Dark Core' May Not Be So Dark After All

Astronomers were puzzled earlier this year when NASA's Hubble Space Telescope spotted an overabundance of dark matter in the heart of the merging galaxy cluster Abell 520. This observation was surprising because dark matter and galaxies should be anchored together, even during a collision between galaxy clusters.

Astronomers have abundant evidence that an as-yet-unidentified form of matter is responsible for 90 percent of the gravity within galaxies and clusters of galaxies. Because it is detected via its gravity and not its light, they call it "dark matter."

Now, a new observation of Abell 520 from another team of astronomers using a different Hubble camera finds that the core does not appear to be over-dense in dark matter after all. The study findings were published in The Astrophysical Journal.

"The earlier result presented a mystery. In our observations we didn't see anything surprising in the core," said study leader Douglas Clowe, an associate professor of physics and astronomy at Ohio University. "Our measurements are in complete agreement with how we would expect dark matter to behave."

Hubble observations announced earlier this year by astronomers using Hubble's Wide Field Planetary Camera 2 suggested that a clump of dark matter was left behind during a clash between massive galaxies clusters in Abell 520, located 2.4 billion light-years away. The dark matter collected into a "dark core" that contained far fewer galaxies than would be expected if the dark and luminous matter were closely connected, which is generally found to be the case.

Because dark matter is not visible, its presence and distribution is found indirectly through its gravitational effects. The gravity from both dark and luminous matter warps space, bending and distorting light from galaxies and clusters behind it like a giant magnifying glass. Astronomers can use this effect, called gravitational lensing, to infer the presence of dark matter in massive galaxy clusters. Both teams used this technique to map the dark matter in the merging cluster.

Clowe's team used Hubble's Advanced Camera for Surveys (ACS) to measure the amount of dark matter in the cluster. ACS observed the cluster in three colors, allowing the astronomers to distinguish foreground and background galaxies from the galaxies in the cluster. From this observation, the team made an extremely accurate map of the cluster's dark matter. "With the colors we got a more precise selection of galaxies," Clowe said.

The astronomers estimated the amount of dark matter in the cluster by measuring the amount of gravitational "shear" in the Hubble images. Shear is the warping and stretching of galaxies by the gravity of dark matter. More warping indicates the presence of more gravity than is inferred from the presence of luminous matter, therefore requiring the presence of dark matter to explain the observation. "The WFPC2 observation could have introduced anomalous shear and not a measure of the dark matter distribution," Clowe explained.

Using the new camera, Clowe's team measured less shear in the cluster's core than was previously found. In the study the ratio of dark matter to normal matter, in the form of stars and gas, is 2.5 to 1, which is what astronomers expected. The earlier WFPC2 observation, however, showed a 6-to-1 ratio of dark matter to normal matter, which challenged theories of how dark matter behaves.

"This result also shows that as you improve Hubble's capabilities with newer cameras, you can take a second look at an object," Clowe said.

His team is encouraging other scientists to study its data and conduct their own analysis on the cluster.

Read more at Science Daily

The Beginning of Everything: New Paradigm Shift for the Infant Universe

A new paradigm for understanding the earliest eras in the history of the universe has been developed by scientists at Penn State University. Using techniques from an area of modern physics called loop quantum cosmology, developed at Penn State, the scientists now have extended analyses that include quantum physics farther back in time than ever before -- all the way to the beginning. The new paradigm of loop quantum origins shows, for the first time, that the large-scale structures we now see in the universe evolved from fundamental fluctuations in the essential quantum nature of "space-time," which existed even at the very beginning of the universe over 14 billion years ago. The achievement also provides new opportunities for testing competing theories of modern cosmology against breakthrough observations expected from next-generation telescopes.

The research will be published on 11 December 2012 as an "Editor's Suggestion" paper in the scientific journal Physical Review Letters.

"We humans always have yearned to understand more about the origin and evolution of our universe," said Abhay Ashtekar, the senior author of the paper. "So it is an exciting time in our group right now, as we begin using our new paradigm to understand, in more detail, the dynamics that matter and geometry experienced during the earliest eras of the universe, including at the very beginning." Ashtekar is the Holder of the Eberly Family Chair in Physics at Penn State and the director of the university's Institute for Gravitation and the Cosmos. Coauthors of the paper, along with Ashtekar, are postdoctoral fellows Ivan Agullo and William Nelson.

The new paradigm provides a conceptual and mathematical framework for describing the exotic "quantum-mechanical geometry of space-time" in the very early universe. The paradigm shows that, during this early era, the universe was compressed to such unimaginable densities that its behavior was ruled not by the classical physics of Einstein's general theory of relativity, but by an even more fundamental theory that also incorporates the strange dynamics of quantum mechanics. The density of matter was huge then -- 1094 grams per cubic centimeter, as compared with the density of an atomic nucleus today, which is only 1014 grams.

In this bizarre quantum-mechanical environment -- where one can speak only of probabilities of events rather than certainties -- physical properties naturally would be vastly different from the way we experience them today. Among these differences, Ashtekar said, are the concept of "time," as well as the changing dynamics of various systems over time as they experience the fabric of quantum geometry itself.

No space observatories have been able to detect anything as long ago and far away as the very early eras of the universe described by the new paradigm. But a few observatories have come close. Cosmic background radiation has been detected in an era when the universe was only 380-thousand years old. By that time, after a period of rapid expansion called "inflation," the universe had burst out into a much-diluted version of its earlier super-compressed self. At the beginning of inflation, the density of the universe was a trillion times less than during its infancy, so quantum factors now are much less important in ruling the large-scale dynamics of matter and geometry.

Observations of the cosmic background radiation show that the universe had a predominantly uniform consistency after inflation, except for a light sprinkling of some regions that were more dense and others that were less dense. The standard inflationary paradigm for describing the early universe, which uses the classical-physics equations of Einstein, treats space-time as a smooth continuum. "The inflationary paradigm enjoys remarkable success in explaining the observed features of the cosmic background radiation. Yet this model is incomplete. It retains the idea that the universe burst forth from nothing in a Big Bang, which naturally results from the inability of the paradigm's general-relativity physics to describe extreme quantum-mechanical situations," Agullo said. "One needs a quantum theory of gravity, like loop quantum cosmology, to go beyond Einstein in order to capture the true physics near the origin of the universe."

Earlier work with loop quantum cosmology in Ashtekar's group had updated the concept of the Big Bang with the intriguing concept of a Big Bounce, which allows the possibility that our universe emerged not from nothing but from a super-compressed mass of matter that previously may have had a history of its own.

Even though the quantum-mechanical conditions at the beginning of the universe were vastly different from the classical-physics conditions after inflation, the new achievement by the Penn State physicists reveals a surprising connection between the two different paradigms that describe these eras. When scientists use the inflation paradigm together with Einstein's equations to model the evolution of the seed-like areas sprinkled throughout the cosmic background radiation, they find that the irregularities serve as seeds that evolve over time into the galaxy clusters and other large-scale structures that we see in the universe today. Amazingly, when the Penn State scientists used their new loop-quantum-origins paradigm with its quantum-cosmology equations, they found that fundamental fluctuations in the very nature of space at the moment of the Big Bounce evolve to become the seed-like structures seen in the cosmic microwave background.

"Our new work shows that the initial conditions at the very beginning of the universe naturally lead to the large-scale structure of the universe that we observe today," Ashtekar said. "In human terms, it is like taking a snapshot of a baby right at birth and then being able to project from it an accurate profile of how that person will be at age 100."

"This paper pushes back the genesis of the cosmic structure of our universe from the inflationary epoch all the way to the Big Bounce, covering some 11 orders of magnitude in the density of matter and the curvature of space-time," Nelson said. "We now have narrowed down the initial conditions that could exist at the Big Bounce, plus we find that the evolution of those initial conditions agrees with observations of the cosmic background radiation."

Read more at Science Daily

Mayans Cooked Food With Clay Balls

Planning a last supper party on December 21? To celebrate the Mayan way, you might need several clay balls.

That's one way the Maya cooked their food, according to U.S. archaeologists who have unearthed dozens of rounded clay pieces from a site in Mexico.

Conducted with the Instituto Nacional de Antropología e Historia (INAH) and Millsaps College's financial support, the excavation of a kitchen at Escalera al Cielo in Yucatán revealed 77 complete balls and 912 smaller fragments.

About 1-2 inches in diameter and more than 1,000 years old, the clay balls contained microscopic pieces of maize, beans, squash and other root crops.

The finding supports the hypothesis that the balls "were involved in kitchen activities related to food processing," archaeologists Stephanie Simms, Francesco Berna, of Boston University, MA, and George Bey of Millsaps College, MS, wrote in the Journal of Archaeological Science.

"This is the first time fired clay balls have been studied in the Maya area and, to my knowledge, no one has documented the use of clay balls in modern Maya cooking," Simms told Discovery News.

Located in the Puuc Maya hills of Yucatán, Escalera al Cielo was an elite residential settlement that was rapidly abandoned sometime near the end of the Terminal Classic period (800-950 A.D.), as shown by ceramic vessels, stone tools, personal adornments, and other materil assembled on the floors.

"We know much about the nature of ancient Maya kings and queens, but this type of study helps see how the Maya worked in the kitchen, what kinds of tools they used and the ways they might have prepared their cuisine," Bey, the project co-director along with archaeologist Tomás Gallareta Negrón and anthropologist William Ringle, told Discovery News.

To better understand the meaning of the fired clay balls, the researchers used a suite of microscopic techniques and experimental replication. The tests revealed that the balls were produced from local clay in a standardized set of sizes.

"They were fired at a fairly low temperature and were used repeatedly in the kitchen," Bey said.

Most likely, the fired clay balls were either placed directly into pots of food to cook or heat it, or used in pit (pib in Mayan) oven cooking installations.

"This cooking method involves digging a shallow pit, lining it with stones or clay balls, building a fire on top and waiting until it is reduced to embers," Simms said.

The process continued by placing whole roots, squash fruits or packets of food wrapped in maize on the hot stones. Everything was then covered with earth and leaves to seal in heat. Cooking took from one hour to up to a day or more.

The experimental tests showed "how the ancient Puuc Maya manipulated materials available to them to produce objects that potentially represent a staple of every Puuc Maya kitchen inventory, maybe even representing a local cooking technique and cuisine," Simms said.

Fired clay balls have been described from a variety of archaeological contexts worldwide, particularly in the Lower Mississippi River Basin and southeastern United States, and in areas of southwest Asia where clay is abundant but stone are not. Similar clay balls were also unearthed in the neolithic village of Catalhoyuk in Turkey, where they were found in hearths and interpreted as cooking or heating implements.

Read more at Discovery News

Organics Discovered on Mercury

NASA dispatched the Curiosity rover to Mars to look for organics, but a probe orbiting Mercury has beaten it to the punch.

New results from the MESSENGER spacecraft not only confirm that the planet closest to the sun has ice inside shaded craters near the north pole, but that a thin layer of very dark organic material seems to be covering a good part of the frozen water.

Both likely arrived via comets or asteroids millions -- or hundreds of millions -- of years ago.

Unlike Curiosity, which will be directly sampling Martian rocks and soils to look for signs of organic material, MESSENGER bounces laser beams and counts neutrons and gamma rays to collect information remotely about chemical elements on Mercury’s surface.

The information is correlated with detailed topographical and temperature maps, laboratory tests and computer models and then compared with candidate materials to find the best match for the observed conditions.

After years of painstaking work, scientists believe the most likely explanation is that the warmer parts of the shadowed craters contain black patches of organic material overlaying ice. The material, which is somewhat like tar, coal and soot, is believed to be similar to what has been observed on icy bodies in the outer solar system and in the nuclei of comets.

"It could easily have been delivered by comets and asteroids, along with water ice, and may even have darkened in the Mercury environment in response to the intense radiation and space weathering," lead MESSENGER scientist Sean Solomon, with Columbia University, told Discovery News.

"Certainly the darkness of the covering material was a surprise and the explanation that seems to fit all the data is that it’s organic material. It's quite interesting," Solomon said.

While there is no direct evidence the dark patches are organic materials, scientists say it is the only explanation that fits all of the conditions.

"The idea here is that this dark material was somehow cold-trapped along with the water and then the water sublimated (transformed from solid to vapor), leaving this dark deposit behind," planetary scientist David Paige, with the University of California, Los Angeles, told Discovery News.

"It's not just a crazy hypothesis and no one has got anything else that seems to fit all the observations better," Paige said.

The finding may have implications in the search for life beyond Earth. The chemistry for life, as we know it, requires organics, liquid water and a source of heat. While there is no hard evidence for liquid water on Mercury, it could exist inside the planet beneath the ice.

"It really depends on the thickness of the (ice) deposits and how long some of them have been around. As you go deeper into a planet it warms. Temperature increases with depth," Solomon said.

Over time, a barrage of impacts could have turned the surface, bringing ice to greater depths and closer to the temperatures needed to turn to liquid.

"There might be liquid water beneath some of these permanently shadowed regions," Solomon said.

In addition, scientists suspect impacts as well as solar and cosmic radiation are triggering chemical reactions in the organic material, turning it about twice as dark as Mercury's surface.

"Is there chemistry going on in some portion of the subsurface where liquid water is present, organic material is present and there’s the equivalent of geothermal energy? I think that's something we need to pursue," Solomon said.

Even if Mercury isn't a good candidate to look for ancient life, the planet may hold clues about how life got started on Earth.

Read more at Discovery News

Small Galaxy Packs Black Hole Whopper

Astronomers have found a super-super-massive black hole comprising a whopping and unprecedented 59 percent of the mass of stars in the central bulge of its host galaxy, a discovery that adds a new twist to the mysterious relationship between a galaxy and its black hole.

The black hole inside the small, compact galaxy known as NGC 1277, located about 250 million light years away in the constellation Perseus, weighs in at 17 billion times the mass of the sun.

In comparison, the supermassive black hole at the heart of our Milky Way galaxy is equal to the mass of about 4 million suns.

Typically, black holes account for 0.1 percent of a galaxy's stellar bulge. Until now, the galaxy with the proportionally largest black hole was NCG 4486B, which has a black hole accounting for 11 percent of the combined mass of the central stars.

How 1277's black hole came to be so large is mystery.

"We didn't expect these systems to exist at all, but because the stars move so incredibly fast in the centers of these objects, we know these big black holes exist in these small galaxies," astronomer Remco van den Bosch, with the Max Planck Institute for Astronomy in Germany, wrote in an email to Discovery News.

"Now that we have found that these crazy kind of galaxies exist, we want to know how they form and how (un-)common they are," he wrote.

However the galaxy and its black hole came to cohabitate, they've been together and in relative peace for a long, long time.

The galaxy has a flat disk, indicating its stars are, and have been, relatively undisturbed for eons. If the black hole had been feeding, the flux of infalling material would have triggered new star formation, van den Bosch said.

"This black hole -- and galaxy -- must have formed in its final form fairly quickly after the big bang. We do not have any information on whether the black hole formed before the galaxy, but most likely it happened at the same time," van den Bosch wrote.

Read more at Discovery News

Bizarre Insectlike Creatures Found in Spanish Cave

Three bizarre-looking springtails, tiny insectlike creatures, have been discovered in a Spanish cave.

Springtails are amongst the most ancient and widespread animals on the planet. Like insects, they have six legs, but are small, more primitive and lack wings. They usually have a furca, or a tail used to spring away from danger, hence the name "springtails." Many cannot be seen with the naked eye; the largest species is about 0.24 inches long (6 millimeters).

The three species — dubbed Pygmarrhopalites maestrazgoensis, P. cantavetulae and Oncopodura fadriquei — are very different from one another. But each of the new species has the requisite springy tails and hairy, tiny bodies, resembling Lilliputian monsters. One of them, O. fadriquei, lacks eyes.

They were found by researchers from Spain's University of Navarra in the isolated Maestrazgo caves in the Teruel region of Spain, at elevations up to 6,560 feet (2,000 meters). Outside the isolated caves, winter temperatures drop to minus 40 degrees Fahrenheit (minus 40 degrees Celsius). Inside, however, temperatures stay between 41 and 54 F (5 to 11 C).

The scientists plan to study how these creatures adapt to the cold, wet and lightless conditions in the cave, according to a release from the Spanish Foundation for Science and Technology.

"Like other cave-adapted animals, the [springtails] require greater chemical sensitivity as they cannot use their sight in the absence of light," said University of Navarra researcher Enrique Baquero in the statement.

Read more at Discovery News

LHC Creates New Form of Matter

Collisions between particles inside the Large Hadron Collider atom smasher have created what looks like a new form of matter.

The new kind of matter is called color-glass condensate, and is a liquidlike wave of gluons, which are elementary particles related to the strong force that sticks quarks together inside protons and neutrons (hence they are like "glue").

Scientists didn't expect this kind of matter would result from the type of particle collisions going on at the Large Hadron Collider at the time. However, it may explain some odd behavior seen inside the machine, which is a giant loop where particles race around underneath Switzerland and France.

When scientists sped up protons (one of the building blocks of atoms) and lead ions (lead atoms, which contain 82 protons each, stripped of their electrons), and crashed them into each other, the resulting explosions liquefied those particles and gave rise to new particles in their wake. Most of these new particles, as expected, fly off in all directions at close to the speed of light.

But recently scientists noticed that some pairs of particles were flying off from the collision point in correlated directions.

"Somehow they fly at the same direction even though it's not clear how they can communicate their direction with one another. That has surprised many people, including us," MIT physicist Gunther Roland, whose group led the analysis of the collision data along with Wei Liof Rice University, said in a statement.

A similar flight pattern is seen when two heavy particles, such as lead and lead, crash into each other. In this case, the collisions create what's called quark-gluon plasma -- a superhot soup of particles similar tothe state of the universe just after the Big Bang. This soup can sweep particles in the same direction, explaining why their flight directions would be correlated.

But quark-gluon plasma isn't possible with lead-proton collisions, like the ones in the new study. Now researchers think a different state of matter, the color-glass condensate, may act in a similar way. The color-glass condensate's dense swarm of gluons may also sweep particles off in the same direction, suggested Brookhaven National Laboratory physicist Raju Venugopalan, who first predicted the substance, which may also be seen after proton-proton collisions.

The mechanism may depend on a weird quirk of particles called quantum entanglement. Two particles can be entangled so that they retain a connection even after they are separated, and an action on one reverberates on the other.

Entangled gluons in the color-glass condensate could explain how particles flying away from the collision point might share information about their flight direction with each other, Venugopalan said.

Read more at Discovery News

Human Poo Leaves Archeological Stain in Norway

Human feces are smeared all over the geological record of places people have inhabited. The chemical signature of human excrement was analyzed in sediments in a northern Norwegian lake. Starting around 2,250 years ago, the presence of people’s poo painted a picture of human population changes in the region around Lake Liland on one of the Lofoten Islands.

"Without even knowing it, early settlers were recording their history for us, and in the most unlikely of ways, in their poop,” said study author Robert D’Anjou, University of Massachusetts geosciences doctoral student. “The prehistoric settlers and their livestock pooped and their feces washed into the lake, which over time left a record of trace amounts of specific molecules that are only produced in the intestines of higher mammals. When you find these molecules at certain concentrations and in specific ratios, it provides an unmistakable indicator that people were living in the area."

The chemical coprostanol is produced during the digestion of cholesterol in the human gut. The chemical collects in sediments after people’s feces are flushed into bodies of water. The sediments provided evidence that from 7,300 years ago to 2,250 years ago, the region had no observable human habitation. Human and domesticated animals’ fecal signatures began showing up after that time. Two different molecular markers were also used to look for evidence of forest clearing through burning.

Population density was low in the region for much of its history, until reaching a peak in 500 A.D. A low spot in 850 suggested the area was depopulated at that time. Human presence fluctuated until dropping to another low spot in 1750.

Read more at Discovery News

Climate Change Threatens French Truffle

Scientists said on Tuesday they had proof that climate change was hitting the Perigord black truffle, a delight of gourmets around the world.

Trufflers have long suspected that global warming is affecting Tuber melanosporum, dubbed "the black diamond" on account of its color and extraordinary price, in its native habitat in southwestern France, Spain, and Italy.

A century ago, French trufflers notched up a harvest that, according to legend, reached 1,000 tonnes in a year.

In the 1960s, truffle yields were still 200-300 tonnes annually.

But in recent years, they have been a meager 25 tonnes or so, prompting retail prices to rocket to as high as 2,000 euros ($2,500) a kilo.

In a letter to the journal Nature Climate Change, Swiss scientists said they now had clear data that drier summers were to blame, as this affected the oak and hazelnut trees on which the prized fungi grows, a process known as symbiosis.

The team found that harvests in France's Perigord and in Spain's Aragon region fell at roughly the same pace from 1970-2006, and this trend was in line with an overall decline in summer rainfall.

Harvests in northern Italy's Piedmont and Umbria also retreated, but not as badly as in France and Spain, and this correlated with relatively higher levels of summer rain in those regions.

Harvesting of the black truffle, also called the Mediterranean truffle, is restricted to the months between November and February.

However, the success of the yield depends on the summer's weather, explained Ulf Buentgen and Simon Egli from the Swiss Federal Research Institute, or WSL.

Truffles thrive in wet and cold conditions and hate dryness and heat.

"Given the symbiotic fungi-host association, we postulate that competition for summer soil moisture... might be a critical factor for truffle fruit body production, particularly in semi-arid environments," they said.

Their theory, they added, is borne out by research in Spain, which found that oak tree growth depends overwhelmingly on rain between May and July.

Read more at Discovery News

1,000-Year-Old Muslim Joke Book Found

An 11th-century book by a revered Baghdad Muslim scholar turns out to be a tongue-in-cheek guide for party crashers, according to the researcher who translated the book into English.

The tome was originally authored by al-Khatib al-Baghdadi, a well known scholar of the Prophet Mohammed's teachings.

According to Emily Selove of the University of Manchester, who did the translation, he wrote the book to remind readers "that every serious minded person needs to take a break."

She continued, "This book, which contains flirtation, profanity, and even a little drunkenness, is a lot of fun and offers a rather different perspective to the austere image Islam has from that period. The reality is that the Baghdad of 1,000 years ago was actually rather Bohemian -- it wasn't perfect by any means -- but not the violent and repressive society you might imagine it was."

"Such ignorance is probably down to the fact that so little of the huge body of literature produced at that time has been translated into English. There's so much more to do."

Selove, however, added, "Though it's light and really quite an enjoyable read, there are serious messages too. The book is about generosity and encouraging individuals to express themselves eloquently and clearly."

"It also suggests that turning a hungry person away from a place laden with food was cruel -- as food was sometimes in short supply to the poor. It castigated those who turned gate crashers away from parties as misers. You do not turn people away if they are hungry."

Humor, though, is peppered through the book. It even contains a piece of satire: a fictional document commissioned by a Caliph on the creation of a "Government office for Gatecrashing."

Jokes

Here are some of the jokes:

Once a man crashed another man's party. "Who are you?" the host asked him. "I'm the one who saved you the trouble of sending an invitation!" he replied.

A party-crasher walked into a gathering, and they said to him, "Nobody invited you!" "But if you didn't invite me and I didn't come," he replied, "think how lonely that would be!"

Once a party-crasher walked in the house of a man who had invited a gathering of people. "Hey, you!" the man said. "Did I say you could come?" "Did you say I couldn't come?" the party crasher replied.

Someone asked a party-crasher, "What's four times four?" "Sixteen loaves of bread," he said. "What is two times two?" "Four loaves of bread," he replied. And another time he said, "I waited the amount of time it takes someone to eat a loaf of bread."

Bunan (a popular rogue at the time that Selove likens to a cross between Falstaff and Robin Hood) had eaten and eaten well, and someone said to him, "Slow down! You'll kill yourself!" "If it is time to die," Bunan replied, "I want to go well fed and well watered, not parched and hungry."

A party-crasher took up with a man while traveling. One day the man said to him, "“Go and buy some meat for us." "No, by God, I don't have the means," said the party-crasher. So the man went and bought the meat. Then he said, "Get up and cook it." "I'm no good at cooking," said the party-crasher. So the man cooked the meat. Then he said, "Get up and sop the bread," and the party-crasher replied, "By God, I feel exhausted." So the man sopped the bread. Then he said, "Get up and ladle the stew." "I'm afraid I'll spill it on my robe," said the party-crasher, so the man ladled the stew. "Get up and eat," he said. "By God," said the party-crasher, "I've been feeling bad for refusing you so many times," and he came forward and ate.

Advice

The book also contains advice:

A man said to Bunan, "Counsel me!"

"Don't fraternize," he replied, "but if you can't avoid it, pick someone who won't pester you. Don't go for greens, gorge on chicken skin, stuff yourself with goat kidneys, gulp bird gizzards, snatch fish innards, or concern yourself with the eyeballs if a head is served. And pay no attention to skinny poultry. Think of naught but what is in your plate, nor glance upon the plates of the others. And if the roast goat when passed to you has little meat left on it, pity not the weakness of the aged guests, nor the greed of the young. Eat, and don't bother yourself with the host's family, and don't waste time inquiring after their health."

Read more at Discovery News