OLDEST MAN-MADE STRUCTURE FOUND IN GREEK CAVE

The oldest known example of a man-made structure was found within a prehistoric cave in central Greece, according to the Greek culture ministry.

The structure is a stone wall that blocked two-thirds of the entrance to the Theopetra cave near Kalambaka on the north edge of the Thessalian plain. It was constructed 23,000 years ago, probably as a barrier to cold winds.

“An optical dating test, known as Optically Stimulated Luminescence, was applied on quartz grains nested within the stones. We dated four different samples from the sediment and soil materials, and all provided identical dates,” Nikolaos Zacharias, director of the laboratory of archaeometry at the University of Peloponnese, told Discovery News.

According to a statement by the ministry of culture, “the dating matches the coldest period of the most recent ice age, indicating that the cavern’s inhabitants built the stone wall to protect themselves from the cold.”

Excavated since 1987, the Theopetra cave is well known to palaeontologists as it was used and inhabited continuously from the Palaeolithic period onwards (50,000 to 5,000 years ago).

“The newly discovered stone structure is important as it shows the technological level of humans at that time,” Zacharias said.

Source: http://news.discovery.com

Read more »

Forever young: Secret of eternal life revealed by Russian science?

Read more »

World's largest flower

The flower with the world's largest bloom is the Rafflesia arnoldii. This rare flower is found in the rainforests of Indonesia. It can grow to be 3 feet across and weigh up to 15 pounds! It is a parasitic plant, with no visible leaves, roots, or stem. It attaches itself to a host plant to obtain water and nutrients. When in bloom, the Rafflesia emits a repulsive odor, similar to that of rotting meat. This odor attracts insects that pollinate the plant.

Source <www.loc.gov>

Read more »

Clownfish Change Size And Sex To Move Up The Ranks

What the movie "Finding Nemo" doesn't tell you about clownfish is that they're all transsexuals. In a study published in the journal Nature, evolutionary biologist Peter Buston and colleagues report that clownfish in Papua New Guinea reefs can change their sex at will for social reasons. Clownfish live in strict hierarchical communities. Each neighborhood is dominated by a top-ranking female breeder. Her male partner is next, followed by up to four progressively smaller, non-breeding fish. When the dominant female dies, her mate changes sex and becomes female. The top-ranking non-breeder becomes a sexually active male, and all the other fish shift up a rank. Clownfish also appear to regulate their size in order to remain part of the group. Each fish keeps its body mass 20 percent smaller than the fish directly above it in social rank, probably to avoid conflict. Fish who disrespectfully outgrow their rank are rejected by the clan.

Source <www.flmnh.ufl.edu>

Read more »

World's smallest flowering plant

The world's smallest fruit is naturally created by the world's smallest flowering plant, genus Wolffia, a part of the duckweed family., the smallest of which are the Australian Wolffia angusta and the Asian/African Wolffia globosa.

The plant itself measures about 1 mm long and the fruit is no bigger than a grain of salt.

A Bouquet on the Head of a Pin!

I can't overemphasize how tiny these little guys are, as a dozen Wolffia blooms could be arranged tastefully on the head of a pin. While they are flowering plants capable of producing seeds, Wolffia reproduces most commonly by vegetative means. A mature plant will produce a bud which will grow into an individual plant and separate off from the parent. Their capacity for vegetative reproduction is incredible, as the Indian species Wolffia microscopica can produce a smaller daughter plant every 30 to 36 hours. At this rate of reproduction, one plant could give rise to about 1 nonillion (a one followed by 30 zeros) in a period of only 4 months. Fortunately, these plants are edible and are similar to soybeans in their protein content. In fact, Wolffia is eaten by people in Thailand. It is known there as "water-eggs" or khai-nam.
A Large Future for such a Small Plant

Wolffia have the potential to help solve some of the world's most pressing problems, from bioremediation of polluted waters to serving as a food source for humans and animals, to even providing biofuel to lessen our dependence on oil. Such amazing possibilities for such a diminutive plant, and incurably cute, too!

Source <http://davesgarden.com>

Read more »

Natural Viagra: Brazilian Spider Bite Causes Hours-Long Erection

A Brazilian spider delivers more than a painful bite that sends most victims to the hospital.

Its venom stimulates an hours-long erection. Now scientists have figured out the chemical that seems to be responsible for the penis boost.

In Brazil, emergency room staff can immediately spot the victims of a bite from the Brazilian wandering spider (Phoneutria nigriventer).

Patients not only experience overall pain and an increase in blood pressure, they also sport an uncomfortable erection.

"The erection is a side effect that everybody who gets stung by this spider will experience along with the pain and discomfort," said study team member Romulo Leite of the Medical College of Georgia, presumably speaking only about male bite victims. "We're hoping eventually this will end up in the development of real drugs for the treatment of erectile dysfunction."


Source <www.foxnews.com>

Read more »

Why Does Scratching Feel So Good?

Have you ever wondered why scratching an itch feels so good?

Well, researchers at Wake Forest University Baptist Medical Center in North Carolina may have finally answered that burning question.

“Our study shows for the first time how scratching may relieve itch,” said lead author Dr. Gil Yosipovitch in a news release.

“It’s important to understand the mechanism of relief so we can develop more effective treatments. For some people, itch is a chronic condition that affects overall health.”

For the study, researchers used functional magnetic response imaging (MRI) technology to monitor 13 healthy volunteers while they scratched on their lower leg with a small brush. The scratching went on for 30 seconds and was then stopped for 30 seconds — for a total of about five minutes.

“To our surprise, we found that areas of the brain associated with unpleasant or aversive emotions and memories became significantly less active during the scratching,” said Yosipovitch. “We know scratching is pleasurable, but we haven’t known why. It’s possible that scratching may suppress the emotional components of itch and bring about its relief.”

The reduced brain activity occurred in the anterior cingulate cortex, an area associated with aversion to unpleasant sensory experiences, and the posterior cingulate cortex, which is associated with memory. When participants reported that the scratching felt most intense, activation in these areas was lowest.

“This is the first real scientific evidence showing that itch may be inhibited by scratching,” he said. “Of course, scratching is not recommended because it can damage the skin. But understanding how the process works could lead to new treatments. For example, drugs that deactivate this part of the brain might be effective.”

Source <www.foxnews.com>

Read more »

New hope for HIV vaccine efforts

By Helen Briggs
Health reporter, BBC News

The HIV virus fusing with a T cell

US researchers say they are a step closer to understanding why some people have natural protection against HIV.

They believe rare individuals who progress very slowly to AIDs when infected make white blood cells that are better at fighting the virus.
The findings, published in Nature, may help international efforts to design an effective AIDS vaccine.
But the research team at MIT and Harvard says any such vaccine is at least a decade away.
The findings relate to so-called "elite controllers" - a small number of people who, when exposed to HIV, progress very slowly to AIDS or never develop it at all.

It shows another piece in the puzzle of what we want a vaccine to do Prof Arup Chakraborty

In the late 1990s it was discovered that these individuals - about one in 200 of those infected with HIV - carry a specific gene, known as HLA B57.
The research team, led by MIT Professor Arup Chakraborty and Harvard Professor Bruce Walker, found this gene causes the body to make more potent killer T cells - a type of white blood cell that fights infections.
This helps them to keep the HIV virus at bay, but also makes them more susceptible to autoimmune diseases, where the body's immune system turns on itself.
The work is based on computer modelling of how immune cells develop in a specialised organ of the immune system known as the thymus.
Vaccine puzzle
The researchers say the study has implications for designing an effective vaccine.
It could help them develop vaccines that provoke the same response to HIV that individuals with "natural immunity" can do on their own.
But they say even if they knew exactly what vaccine they wanted to make, it would take at least a decade to reach the hands of a healthcare worker.
Prof Bruce Walker told the BBC: "Some people are able to control HIV on their own and it's really critical for us to understand how this happens. This study takes us a step forward in understanding that."
Prof Chakraborty added: "It shows another piece in the puzzle of what we want a vaccine to do."
Genetic defences
Commenting on the study, Jason Warriner, Clinical Director at Terrence Higgins Trust, said: "Anything that gives us greater insight into genetic defences related to HIV is useful in searching for a vaccine and, one day, a cure for this complex virus.
"However, these elite controllers are a tiny proportion of people and they are not immune from HIV-related illnesses.
"HIV remains the UK's fastest-growing serious health condition, with 83,000 people affected, so it is vital that people continue to use condoms to protect themselves."
The study is published online in the journal Nature.

Source: www.bbc.co.uk

Read more »

An immortal creature found

The Turritopsis Nutricula is able to revert back to a juvenile form once it mates after becoming sexually mature.

Marine biologists say the jellyfish numbers are rocketing because they need not die.

Dr Maria Miglietta of the Smithsonian Tropical Marine Institute said: "We are looking at a worldwide silent invasion."

The jellyfish are originally from the Caribbean but have spread all over the world.

Turritopsis Nutricula is technically known as a hydrozoan and is the only known animal that is capable of reverting completely to its younger self.

It does this through the cell development process of transdifferentiation.

Scientists believe the cycle can repeat indefinitely, rendering it potentially immortal.

While most members of the jellyfish family usually die after propagating, the Turritopsis nutricula has developed the unique ability to return to a polyp state.

Having stumbled upon the font of eternal youth, this tiny creature which is just 5mm long is the focus of many intricate studies by marine biologists and geneticists to see exactly how it manages to literally reverse its aging process.

Source: http://www.telegraph.co.uk

Read more »

Your fat may help you heal

It frequently happens in science that what you throw away turns out to be most valuable. It happened to Deepak Nagrath, but not for long.
The Rice assistant professor in chemical and biomolecular engineering was looking for ways to grow cells in a scaffold, and he discarded the sticky substance secreted by the cells.
"I thought it was contamination, so I threw the plates away," said Nagrath, then a research associate at Harvard Medical School.

Nagrath, who joined Rice in 2009, and his co-authors have since built a biological scaffold that allows cells to grow and mature. He hopes the new material, when suffused with stem cells, will someday be injected into the human body, where it can repair tissues of many types without fear of rejection.
The research by Nagrath and his co-authors appeared last week in the Federation of American Societies for Experimental Biology (FASEB) Journal.
The basic idea is simple: Prompt fat cells to secrete what bioengineers call "basement membrane." This membrane mimics the architecture tissues naturally use in cell growth, literally a framework to which cells attach while they form a network. When the cells have matured into the desired tissue, they secrete another substance that breaks down and destroys the scaffold.
Structures that support the growth of living cells into tissues are highly valuable to pharmaceutical companies for testing drugs in vitro. Companies commonly use Matrigel, a protein mixture secreted by mouse cancer cells, but for that reason it can't be injected into patients.
"Fat is one thing that is in excess in the body. We can always lose it," Nagrath said. The substance derived from the secretions, called Adipogel, has proven effective for growing hepatocytes, the primary liver cells often used for pharmaceutical testing.
"My approach is to force the cells to secrete a natural matrix," he said. That matrix is a honey-like gel that retains the natural growth factors, cytokines (substances that carry signals between cells) and hormones in the original tissue.
Nagrath's strategy for growing cells isn't the only approach being pursued, even at Rice: Another method reported last week in Nature Nanotechnology uses magnetic levitation to grow three-dimensional cell cultures.

But Nagrath is convinced his strategy is ultimately the most practical for rebuilding tissue in vivo, and not only because it may cost significantly less than Matrigel. "The short-term goal is to use this as a feeder layer for human embryonic stem cells. It's very hard to maintain them in the pluripotent state, where they keep dividing and are self-renewing," he said.
Once that goal is achieved, Adipogel may be just the ticket for transplanting cells to repair organs. "You can use this matrix as an adipogenic scaffold for stem cells and transplant it into the body where an organ is damaged. Then, we hope, these cells and the Adipogel can take over and improve their functionality."
Source <www.scienceblog.com>

Read more »

Nouns and verbs are learned in different parts of the brain

Two Spanish psychologists and a German neurologist have recently shown that the brain that activates when a person learns a new noun is different from the part used when a verb is learnt. The scientists observed this using brain images taken using functional magnetic resonance, according to an article they have published this month in the journal Neuroimage.

"Learning nouns activates the left fusiform gyrus, while learning verbs switches on other regions (the left inferior frontal gyrus and part of the left posterior medial temporal gyrus)", Antoni Rodríguez-Fornells, co-author of the study and an ICREA researcher at the Cognition and Brain Plasticity Unit of the University of Barcelona, tells SINC.

The Catalan researcher, along with psychologist Anna Mestres-Missé, who is currently working at the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig, and neurologist Thomas F. Münte from the Otto-von-Guericke University in Magdeburg, in Germany, have just published the results of their study confirming the neural differences in the map of the brain when a person learns new nouns and verbs in the journal Neuroimage.

The team knew that many patients with brain damage exhibit dissociation in processing these kinds of words, and that children learn nouns before verbs. Adults also perform better and react faster to nouns during cognitive tests.

Read more here

Read more »

The viruses that kill tumours

The idea of using viruses to kill cancers goes back nearly a century. In 1912, an Italian gynaecology journal reported the case of a woman with advanced cervical cancer who, after being bitten by a dog, was vaccinated with a live but weakened strain of the rabies virus. To the doctors' surprise, her tumour shrank.

After more reports of patients' tumours regressing after viral infections or vaccinations, doctors began to take the idea seriously. From the late 1940s onwards, several trials took place in which cancer patients were injected with live viruses. A few individuals showed striking improvements, but the results were mixed overall. Doctors pinned their hopes on chemotherapy and radiotherapy instead, and by the end of 1970s the approach had largely been abandoned.
The perfect bioweapon

While viral-therapy papers gathered dust on library shelves, a revolution was under way in biology. Armed with a burgeoning understanding of how viruses infect cells and a battery of techniques for manipulating their genes, researchers realised that they no longer had to rely on the natural tendency of some viruses to home in on cancer cells.

Read more here

Read more »

Guitarists' Brains Swing Together

When musicians play along together it isn't just their instruments that are in time – their brain waves are too. New research shows how EEG readouts from pairs of guitarists become more synchronized, a finding with wider potential implications for how our brains interact when we do.

Ulman Lindenberger, Viktor Müller, and Shu-Chen Li from the Max Planck Institute for Human Development in Berlin along with Walter Gruber from the University of Salzburg used electroencephalography (EEG) to record the brain electrical activity in eight pairs of guitarists. Each of the pairs played a short jazz-fusion melody together up to 60 times while the EEG picked up their brain waves via electrodes on their scalps.

The similarities among the brainwaves' phase, both within and between the brains of the musicians, increased significantly: first when listening to a metronome beat in preparation; and secondly as they began to play together. The brains' frontal and central regions showed the strongest synchronization patterns, as the researchers expected. However the temporal and parietal regions also showed relatively high synchronization in at least half of the pairs of musicians. The regions may be involved in processes supporting the coordinated action between players, or in enjoying the music.

"Our findings show that interpersonally coordinated actions are preceded and accompanied by between-brain oscillatory couplings," says Ulman Lindenberger. The results don't show whether this coupling occurs in response to the beat of the metronome and music, and as a result of watching each others' movements and listening to each others' music, or whether the brain synchronization takes place first and causes the coordinated performance. Although individual's brains have been observed getting tuning into music before, this is the first time musicians have been measured jointly in concert.

Source <www.sciencedaily.com>

Read more »

THE IMMORTALITY ENZYME

As the human body ages, it loses bone. Individual cells lose something equally vital. Every time one divides, it sheds tiny snippets of DNA known as telomeres, which serve as protective caps on the ends of chromosomes. After perhaps a hundred divisions, a cell's telomeres become so truncated that its chromosomes--site of the cell's genes--begin to fray, rather like shoelaces that have lost their plastic tips. Eventually, such aged cells die--unless, like "immortal" cancer cells, they produce telomerase, an enzyme that protects and even rebuilds telomeres. Scientists have long dreamed of drugs that would inhibit the immortalizing enzyme because, observes M.I.T. biochemist Robert Weinberg, "then maybe cancer cells would run out of telomeres and just poop out."

Wishful thinking? Maybe not. In papers published just a week apart in the journals Science and Cell, two teams of researchers--one led by Nobel-prizewinning biochemist Thomas Cech of the University of Colorado, the other by M.I.T.'s Weinberg--have announced a breakthrough that could help bring about such a drug. Both teams have managed to clone a gene that controls the activity of the telomerase enzyme in human cells. That could set the stage for development not only of inhibiting drugs but also of substances that switch on the enzyme--which might help combat degenerative diseases associated with aging.

Such possibilities, to be sure, are speculative, but that didn't stop Wall Street, where the stock of Geron Corp., a small biotech company based in Menlo Park, Calif., that helped Cech's group discover the gene, more than doubled, to 1618 a share. In fact, Geron researchers have been looking for antitelomerase compounds for several years, using indirect-screening methods. Because tumor cells--the main source of the human enzyme--produce it in vanishingly small quantities, the scientists lacked pure telomerase, which could have sped the search for drugs that might be used against it.

With the new gene in hand, the researchers should be able to churn out at will the protein for which it provides the genetic blueprint. That protein, they believe, is telomerase's most important building block. "For us," exults Calvin Harley, Geron's chief scientist, "it's like having access to an organism's brain."

The new protein, it turns out, bears an intriguing resemblance to an enzyme produced by HIV, the retrovirus that causes AIDS. Indeed, the AIDS drug AZT has already been shown to inhibit telomerase activity. But the viral enzyme and the human enzyme, says Colorado's Cech, are only 20% identical, which explains why AZT is not an ideal telomerase inhibitor. "What we want," he declares, "is a compound that fits telomerase the way a hand fits a glove."

The odds that such a compound will materialize now seem high. But experts caution that it could take years before the first telomerase inhibitors are ready to be tested on humans to determine if they'll have any serious side effects--or if they'll actually inhibit tumor growth. Such questions are perhaps one reason Geron's stock leveled off at week's end, closing at 12 1/4 a share.

Read more: http://www.time.com/time/magazine/article/0,9171,986922,00.html#ixzz0cZsIm6Hv

Read more »

Self-Renewal of Specialized Cells

Is the indefinite expansion of adult cells possible without recourse to stem cell intermediates?

The team led by Michael Sieweke at the Centre d'immunologie de Marseille Luminy (Université Aix-Marseille 2 / CNRS / INSERM) has shown that this is the case by achieving the ex vivo regeneration of macrophages, specialized cells in the immune system, over several months.

Published in Science on November 6, 2009, this discovery could be applied to other cell types. This research enables a clearer understanding of the mechanisms underlying cell differentiation, but above all raises many hopes for potential therapeutic applications.

The regenerative medicine of the future will be based on replacing damaged cells and repairing deficient organs, notably through the use of stem cells. Indeed, these cells are able not only to proliferate indefinitely but, in theory, to supply all types of cells to the human body.

However, the processes that allow the passage from adult (rather than embryonic) cells to stem cells ("reprogramming") are complex and full of risk, as are the processes necessary for the "retransformation" of stem cells into adult cells. The question then arises: might it not be more simple to generate the cells required without passing through the stem cell stage?

Whole Story Here

Read more »

Australian scientists to start 'breast regrowth' trial

It is hoped that if successful, the experimental stem cell breast-growing technique - called Neopec - could replace breast reconstructions and implants within three years.

Dr Phillip Marzella from the Bernard O'Brien Institute of Microsurgery in Melbourne, said a prototype trial of five to six women would start in the next three to six months "to demonstrate that the body can regrow its own fat supply in the breast".

During the world-first trial surgeons will implant a chamber containing a sample of the woman's fat tissue into the chest, which will act a "scaffolding" into which new breast tissue will grow.

"What we are hoping to do in the next two years is develop a biodegradable chamber so that the fat can grow inside the chamber and then the chamber will vanish naturally," Dr Marzella said.

"Nature abhors a vacuum, so the chamber itself, because it is empty, it tends to be filled in by the body."

Dr Marzella said the new breasts would feel normal to the patient.

Whole Story Here

Read more »

How can someone die from drinking too much water?

In January 2007, hours after competing in a radio station contest to win a Nintendo Wii, 28-year-old Jennifer Strange was found dead in her California home. The station's "Hold Your Wee for a Wii" challenge awarded the game system to the contestant who could drink the most water without having to take a trip to the bathroom. According to preliminary autopsy reports, Ms. Strange apparently died from drinking too much water too quickly, resulting in a condition called water intoxication.

At its most basic, water intoxication occurs when a person drinks so much water that the other nutrients in the body become diluted to the point that they can no longer do their jobs. You've probably heard the term electrolyte before, whether in reference to sports drinks (which provide electrolytes in addition to fluids) or to certain conditions, such as bulimia or diarrhea, that cause dangerous "electrolyte imbalances" in the body. Electrolytes are simply salt ions (atoms with an overall positive or negative charge) that cells use to move fluids and nerve messages into and out of cells and throughout the body. Without electrolytes, the body can't function (see What are electrolytes? for a more detailed description). Water intoxication causes an electrolyte imbalance that affects concentrations of the ion sodium, and it leads to a condition called hyponatremia.

In cases of water intoxication, it is extreme hyponatremia that can ultimately cause coma and death. If it's caught early, treatment with IV fluids containing electrolytes can lead to a complete recovery; but untreated, hyponatremia is fatal. Water intoxication is basically one form of hyponatremia -- the condition can also be caused by excessive sweating, severe burns, prolonged dehydration and certain liver and kidney problems, among other diseases and conditions.

When a person dies from hyponatremia as a result of water intoxication, the initiating factor is a severe sodium imbalance that causes massive cell damage. Sodium is a positively charged ion, and its role in the body is to circulate the fluids outside of cells. As a result, sodium helps regulate blood pressure and maintain the signals that let muscles operate properly, among other things. Cells actively maintain a precise sodium concentration in the body. Inside the cell, there are more electrolytes; outside the cell, there is more water. Cells keep sodium levels healthy by moving water and electrolytes into and out of the cell to either dilute or increase sodium levels in body fluids. But when someone drinks a tremendous amount of water in a short period of time, and the water does not contain any added electrolytes, the cellular maintenance system can't handle the level of sodium dilution that occurs.

The result is that cells desperately try to increase the sodium concentration in body fluids by taking in tremendous amounts of water. Some cells can swell a great deal; others cannot. Brain cells are constrained by the skull and can end up bursting with the pressure of the water they are taking in.

The exact amount of water intake that can lead to water intoxication is unknown and varies with each individual. Symptoms of water intoxication actually look a lot like the symptoms of alcohol intoxication, including nausea, altered mental state, and vomiting. Other symptoms include headaches, muscle weakness and convulsions. In severe cases of water intoxication, coma and death come fairly quickly as a result of brain swelling. The condition is quite rare in the general population, but in distance athletics, it's a known risk and is often avoided by drinking sports drinks instead of water during training and events.

Source <http://health.howstuffworks.com/water-intoxication.htm>

Read more »

Curvy women may be a clever bet

Women with curvy figures are likely to be brighter than waif-like counterparts and may well produce more intelligent offspring, a US study suggests.

Researchers studied 16,000 women and girls and found the more voluptuous performed better on cognitive tests - as did their children.

The bigger the difference between a woman's waist and hips the better.

Researchers writing in Evolution and Human Behaviour speculated this was to do with fatty acids found on the hips.

In this area, the fat is likely to be the much touted Omega-3, which could improve the woman's own mental abilities as well as those of her child during pregnancy.

Men respond to the double enticement of both an intelligent partner and an intelligent child, the researchers at the Universities of Pittsburgh and California said.

The findings appear to be borne out in the educational attainments of at least one of the UK's most famous curvaceous women, Nigella Lawson, who graduated from Oxford.

Source <www.bbc.co.uk>

Read more »

Even Babies Have "Accents," Crying Study Finds

Newborn babies start learning language in the womb—and are born with what you might call accents, a new study of crying babies says.That fetuses hear and become accustomed to language is nothing new. Several studies have shown that, when exposed to different languages shortly after birth, a baby will typically indicate a preference for the language closest to the one he or she would've heard during gestation.

But recognizing a language and being able to speak it—or cry it—are two different things.Listening to Babies Cry—By ChoiceFor the new study, a team led by Kathleen Wermke at the Center for Prespeech Development and Developmental Disorders at Würzburg University in Germany studied the cry "melodies" of 60 healthy newborns—30 French and 30 German.The melodies, or intonations, aren't true accents, Wermke cautions—accents have to do with the ways words are pronounced.

The researchers knew that French speakers typically raise their pitch at the ends of words and phrases, while German speakers typically do the opposite.(Related: "Bilingual Babies Get Head Start—Before They Can Talk.")They also knew that melody—or in the case of spoken language, intonation—plays a crucial role in language learning. "This ultimately gave us the idea to look for specific melodic properties in newborns' crying," Wermke said.Intonations Give Babies AwayThe melodies of the newborn babies' cries followed the same intonations of the languages the babies had heard in the womb.

The French babies' cries, for example, tended to end on a rising note."Clearly, the long process of language learning begins with the perception and production of melody by human fetuses and infants," Wermke said.

The discovery may yield more than just an understanding of how language develops."Further analysis of human infants' crying and other utterances," she said, "may contribute to resolving the enigma as to how language may have emerged in early [human ancestors]."

Source < http://news.nationalgeographic.co.uk/news/2009/11/091105-babies-cry-accents.html>

Read more »

Study: Fiddler crabs exchange sex for survival

SYDNEY --In the world of fiddler crabs, the best form of protection for females is, apparently, having sex with the neighbors, according to an Australian study published Wednesday.

Researchers from The Australian National University in Canberra found male fiddler crabs will happily defend a nearby female against intruders -- partly because the females will dole out sex in return.

"The fact that the neighbor comes over and helps to defend another territorial individual is pretty unusual," said Michael Jennions, who helped conduct the study, the results of which were published in the journal Biology Letters.

"This study shows, for the first time, that in exchange for sex and other benefits, males protect their female neighbors from territory-seeking male intruders. The paper provides the first evidence of 'defense coalitions' between territorial males and females," he said.

Jennions and fellow ANU researchers Richard Milner and Patricia Backwell studied the behavior of fiddler crabs living in mud flats off the African country of Mozambique in October and November 2008. Male fiddler crabs have giant claws to defend themselves, but the researchers wanted to see how female crabs -- which only have two small feeding claws -- protect their homes.

Fiddler crabs are territorial and live in burrows. The researchers gathered crabs from distant parts of the mud flats and tethered them near new, occupied burrows. In 21 trials involving male intruders, the researchers found that male crabs would scuttle over to fight off the invaders on a female neighbor's territory 95 percent of the time. But in 20 trials involving female intruders, the males crabs only fought off the invaders 15 percent of the time.

That suggests the male crabs preferred to keep females nearby, largely because they will almost always have sex with their male neighbors, Jennions said.

Most of the time, female fiddler crabs are selective about their partners and choose to mate in the male's burrow. But the researchers also found females mating on the surface -- and 85 percent of the time the surface sex was with a neighbor. The researchers speculated the female crabs were having the neighborly sex in exchange for some sort of benefit. In this case, that benefit appeared to be protection, Jennions said.
Orpha Bellwood, a lecturer of marine and tropical biology at James Cook University in Townsville, said she was particularly interested in the motivations behind the crabs having sex on the surface, which is unusual and makes them vulnerable to predators.

Bellwood wonders whether it might just be the proximity of the crabs to their own homes that allows them to feel safe enough to mate in the open, or whether the females are indeed gaining some sort of protective advantage by doing so.
"It opens up a lot of those questions," she said.

Peter Davie, senior curator of the Queensland Museum in Brisbane, said the males are known to use their claws to protect themselves.
"But to have that sort of encompass the territories of the females as part of his sexual territory sounds quite interesting," said Davie, who has spent 30 years studying crabs.

Swapping sex for favors is not unheard of in the animal kingdom. Antarctica's Adelie penguins exchange sex for highly coveted stones used for nest building.
Another reason the crabs might help fight off their neighbors' intruders is to keep a familiar comrade next door, Jennions said. Even for crabs, he said, sometimes it's a case of "better the devil you know than the devil you don't."

Source  http://www.boston.com/news/science/articles/2009/11/04/study_fiddler_crabs_exchange_sex_for_survival/

Read more »