Microbes in milk…I’m Bob Hirshon and this is Science Update.

Science Update listener Sam from Los Angeles called us with this question:

SAM:

“Why does milk spoil so much faster than other beverages?”

HIRSHON:

For the answer, we consulted Cornell University microbiologist Kathryn Boor. She says because milk promotes the rapid growth of young mammals, it’s full of nutrients.

KATHRYN BOOR (Cornell University):

And as a consequence of its dense nutrient qualities, it also supports rapid growth of microbes.

HIRSHON:

She says this is compounded by the fact that barns are the perfect environment for microbes to enter into the milk supply. Pasteurization, or heating the milk to 161 degrees Fahrenheit for 15 seconds, destroys most bacteria, including those that could potentially harm us, but also those which make milk go sour. And if you have a science question, give us a call at 1-800-why-isit. If we answer your question, you’ll win a Science Update mug! I’m Bob Hirshon, for AAAS, the science society.

Milk is full of nutrients - which support the growth of pathogens - as well as baby mammals. (Keith Weller/USDA)

Ravens’ social memories.  I’m Bob Hirshon and this is Science Update.

[sfx: raven calls]

You’re listening to the calls of different ravens.  And like humans, ravens can identify one another’s voices, and judge whether that voice is friendly or aggressive.  Now, cognitive biologists Markus Boeckle and Thomas Bugnyar of the University of Vienna have shown that ravens can remember past friends and foes for at least three years.  Boeckle says the ravens react differently to recordings of former aggressors, than to those of friendly birds they once encountered.

MARKUS BOECKLE (University of Vienna, Austria):

They try to elongate their vocal tracts and thus, try to sound much deeper than when they are calling back to a friendly individual.

HIRSHON:
Humans do the same thing in adversarial situations.  Bockle says the ravens may have developed long social memories because they spend many years in their birth territory before venturing out to breed.  I’m Bob Hirshon for AAAS, the Science Society.

Ravens remember friend and foe. (Markus Boekle/University of Vienna)

When size matters…I’m Bob Hirshon and this is Science Update.

Holding a weapon makes people seem larger, according to a new study by scientists at UCLA. Evolutionary anthropologist Daniel Fessler and his team had volunteers view pictures of hands holding objects such as power tools, paintbrushes, kitchen knives and guns. Then they had them estimate the size of the person holding the object.

DANIEL FESSLER (UCLA):

And what we show is that when the hand is holding a weapon, they estimate the person attached to that hand being taller and more muscular.

HIRSHON:

He says weapons represent strength in our minds because of their potential threat to our safety.

FESSLER:

Of course, physically their size doesn’t change when they hold a handgun, but behaviorally they become more dangerous. Because all else being equal, the guy with the gun wins.

HIRSHON:

And being able to quickly size up the outcome of potential conflicts probably helped our ancestors survive. I’m Bob Hirshon, for AAAS, the science society.

People judged hands holding weapons as belonging to larger and stronger bodies than hands holding tools. (Daniel Fessler/UCLA)

Did dinosaur gas change the world?  I’m Bob Hirshon and this is Science Update.

Originally called “Thunder Lizards,” those giant, long-necked, plant eating dinosaurs apparently earned that title in more ways than one. New research suggests that these beasts and their kin belched and, well, otherwise emitted so much methane gas that they may have warmed the entire planet! This according to British researchers in a report in the journal Current Biology. In fact, the scientists estimate that the dinosaurs produced more of the greenhouse gas than modern natural and human sources combined!

In other dinosaur news, Chinese paleontologists working in Mongolia have uncovered a prehistoric, jumbo flea that lived during the time of the dinosaurs. Over ten times the size of modern fleas, the bloodsuckers may have burrowed under dinosaurs’ scales. And as fierce as T. rex was, those little forearms probably weren’t much help against a swarm of these little monsters. I’m Bob Hirshon, for AAAS, the science society.

Apatosaurs may have belched their way to a warmer world. (ДиБгд/Wikimedia Commons)

When planets break loose.  I’m Bob Hirshon and this is Science Update.

Our Milky Way galaxy may occasionally hurl planets into deep space at breathtaking speeds.  This according to Dartmouth College and Harvard-Smithsonian astrophysicist Idan Ginsburg.  It’s been shown that this can happen to stars, if they drift too close to the black hole at the center of the galaxy. Now, Ginsburg’s team has calculated that planets orbiting such a star could meet a similar fate.

IDAN GINSBURG (Dartmouth College/Harvard-Smithsonian Center for Astrophysics):

We ran thousands and thousands of simulations, and one of the things that we saw is that not only can these planets get ejected, but under certain circumstances they can get ejected at tremendous velocity, approaching 30 million miles per hour.

HIRSHON:
That’s over 300 times as fast as the Earth orbits the Sun.  For further proof, Ginsburg says runaway planets would have to be detected indirectly, by measuring dips in brightness of the stars they’re ejected with.  I’m Bob Hirshon for AAAS, the Science Society.

An artist's rendering of a runaway planet. (David A. Aguilar/ Harvard-Smithsonian Center for Astrophysics)

Electricity from sewage.  I’m Bob Hirshon and this is Science Update.

As bacteria digest sewage, they also generate electrons.  Scientists have tried to harness this phenomenon through microbial fuel cells, in which bacteria generate usable power as they clean wastewater.  Now, electro-microbiologist Oriana Bretschger, of the J. Craig Venter Institute, has announced big strides this two-in-one technology.  They’ve taken the typical lab prototype and debugged it, scaled it up, and made it cheaper to build.

ORIANA BRETSCHGER (J. Craig Venter Institute):

We’ve moved away from your typical expensive hand-blown laboratory equipment, into something that you could buy from your typical hardware store.

HIRSHON:
Their current model is about the size of a washing machine, removes 97 percent of organic waste from the water, and is up to six times more energy-efficient than past designs.  The researchers hope that eventually, the technology could make wastewater treatment pay for itself, from energy production. I’m Bob Hirshon for AAAS, the Science Society.

An improved “microbial fuel cell” cleans municipal sewage and generates electricity at the same time. (Orianna Bretschger/J. Craig Venter Institute)

Gardening birds…I’m Bob Hirshon and this is Science Update.

Male bowerbirds create elaborate displays, decorating their bowers with colorful fruits, flowers and even shiny manmade objects in order to seduce the opposite sex. But one species, called the spotted bowerbird, may actually be cultivating the fruits the females like best. According toUniversityofExeteranimal behaviorist Joah Madden, female spotted bowerbirds choose males whose bowers sport the largest number of green bush tomato fruits.

When the fruit begins to decay, the male discards it and replaces it with fresh fruit. Madden and his colleagues noticed that about eight times as many bush tomatoes grow near these bowers than you’d expect by chance.

JOAH MADDEN (UniversityofExeter):

And we think it’s these discarded fruits that then are germinating in that area, and then growing up to provide the plants.

HIRSHON:

He adds that human agriculture may have gotten its start when our ancestors unintentionally tossed out seed fruit as well. I’m Bob Hirshon, for AAAS, the society.

A male Spotted Bowerbird adds green fruits to his bower to attract females. (University of Exeter)

An ancient feathered tyrant…I’m Bob Hirshon and this is Science Update.

Scientists recently discovered a relative of Tyrannosaurus rex that had feathers.  The new species is called Yutyrannus huali, which means “beautiful feathered tyrant”, and it lived 60 million years before T. Rex. At over 3000 pounds, it’s the largest feathered dinosaur discovered to date. Even so, its head and body were much smaller than T. Rex’s, according to Corwin Sullivan of the Chinese Academy of Sciences in Beijing. But if it was covered in feathers, could that mean that T. rex was feathered too?

CORWIN SULLIVAN – (Chinese Academy of Sciences in Beijing):

Our find perhaps makes it a little more likely that Tyrannosaurus did have some kind of feathering, in which case the mental image that people have of it would really need to change.

HIRSHON:

But Sullivan explains that Tyrannosaurus lived in a warmer climate than Yutyrannus, and may not have needed feathers for insulation. He adds that the feathers could also have been used for camouflage or for attracting a mate. I’m Bob Hirshon, for AAAS, the science society.

Artist's reconstruction of a group of Yutyrranus huali with feathers. (Brian Choo )

Making a robot shellfish. I’m Bob Hirshon and this is Science Update.

Insects are ubiquitous on land, while shellfish are common in oceans and lakes. Which makes them ideal for collecting data. For example, clandestine cockroaches could spy on enemy outposts, and stealth snails could track submarines. But even tiny cameras and microphones need electricity. In the Journal of American Chemical Society, scientists report that they’ve designed a system of implantable electrodes that turn snails and cockroaches into living batteries that run on a portion of the food they eat.

In other experimental animal news, British researchers have developed zebrafish that glow green when they encounter industrial pollutants called endocrine disrupting chemicals. In addition, the fish glow only in the parts of their bodies effected by the pollutants. Knowing where the chemicals are active in the zebrafish will help scientists better understand the pollutants’ effects on people. I’m Bob Hirshon, for AAAS, the science society.

Therapeutic clockwork.  I’m Bob Hirshon and this is Science Update.

Studies suggest that obesity, diabetes, and other metabolic disorders also disrupt biological clocks.  Now, scientists at the Scripps Research Institute have found that re-setting those clocks may help treat these conditions.  Molecular biophysicist Thomas Burris and his colleagues created drugs that regulate body clocks.  When they tried them on healthy mice, the mice lost weight.

THOMAS BURRIS (Scripps Research Insitute):

And so we put the mice on this high fat diet for a period of time, and then put them on the compound, and the animals would lose weight, and their cholesterol decreased, triglycerides decreased, and they became more insulin-sensitive.

HIRSHON:

This was true even though their diet and food intake didn’t change.  The drugs had a similar effect on genetically obese mice.  Now, Burris wants to find out if the compound can affect other conditions linked to body clock malfunctions, including mental and behavioral illnesses.  I’m Bob Hirshon for AAAS, the Science Society.

The language of kids…I’m Bob Hirshon and this is Science Update.

(baby goat baas)

Baby goats look and sound adorable. But their plaintive calls could be communicating an important message. This according to animal behaviorist Elodie Briefer at Queen Mary University of London. She raised goat kids in several groups, and analyzed their calls at one week of age and again at five weeks. She found that genetics influenced their calls: kids raised in separate groups sounded more similar to their full siblings than to their half siblings. (baby goat baas)

ELODIE BRIEFER (Queen Mary University of London):

But also I found that kids raised in the same group had more similar vocalizations than kids raised in different groups, independently of the fact that they were related or not.

HIRSHON:

What’s more, members of a group sounded more alike over time. She says this is the first time accents have been detected in farm animals, but that having recognizable calls may help the animals find their herdmates after being separated. I’m Bob Hirshon, for AAAS, the science society.

If raised in the same group, baby goat kids start to sound alike over time. (Elodie Briefer/Queen Mary University of London)

You, yourself, and your bacteria… I’m Bob Hirshon and this is Science Update.

When you enter an empty room, you’re not alone. Your mere presence stirs up millions of bacteria and other microorganisms left behind by previous human occupants. Not only that, you emit millions more yourself.

JORDAN PECCIA (YaleUniversity):

Around 35, 37 million bacteria per person per hour and between 5 and 7 million fungi per person per hour.

HIRSHON:

That’s Yale environmental engineer Jordan Peccia. He and his colleagues sampled microbes in rooms when they were occupied and unoccupied.

PECCIA:

Just by a person entering a room, the concentration of bacteria goes up between 10 to 100 times in the air.

HIRSHON:

Since most airborne diseases are transmitted indoors, he says it’s important to understand how our presence affects microbial counts in a room. Fortunately for us, though, only a tiny fraction of those microbes actually cause disease. I’m Bob Hirshon, for AAAS, the science society.

Dreaming in cyberspace…I’m Bob Hirshon and this is Science Update.

These days, smartphone apps seem to do just about everything except clean your house. But can your smartphone influence your dreams? University of Hertfordshire psychologist Richard Wiseman and his team have launched a new app for the iPhone to test this hypothesis. He says dreaming renders us mostly immobile, so the app, called “Dream:ON” uses the iPhone’s motion sensor to detect whether you’re dreaming. Near the end of the night, it quietly starts playing an audio soundscape when it senses you’re in dreamland.

RICHARD WISEMAN (University of Hertfordshire):

So it wakes you up directly after a dream, and prompts you to type in a report of your dream and that comes into our database.

HIRSHON:

The research team will analyze the data to see if hearing birds chirp makes you dream about nature, for example. Wiseman says future research may reveal if certain soundscapes can help people with mood disorders. I’m Bob Hirshon, for AAAS, the science society.

Can listening to a particular soundscape influence your dreams? (Jupiter Images)

Getting a cool reception. I’m Bob Hirshon and this is Science Update.

Researchers at the University of Groningen in the Netherlands report in the journal Psychological Science that an important part of social interaction is imitation: we subconsciously speak and move like the person we’re talking with. But in new research, they found that when another person mimics you either too little or too much, you feel a chill. They suggest that these chills are nature’s way of warning us that the person we’re with may be insincere.

In related news, researchers at Ohio University have found that people who tend to have a lot of anxiety about their relationships, are also more sensitive to temperature cues—for example, if they’re anxious or threatened, they’re more likely to feel chilly and seek out warmth. The research could hold clues into treatments for anxiety disorders and other conditions. I’m Bob Hirshon, for AAAS, the science society.

How predators protect plants.  I’m Bob Hirshon and this is Science Update.

(SFX: Wolf howl)

The howl of the wolf isn’t heard as much as it used to be, and as a result, prey like moose, deer, and elk are thriving.  But according to Oregon State University forestry professor William Ripple, this isn’t a good thing.  He analyzed 42 ecological studies over the past 50 years.  And he found that declines in top predators, especially wolves, lead to a significant loss of plants and trees – because there are more large herbivores like deer to eat them.  And he says we probably can’t do the wolves’ work by hunting the herbivores ourselves.

WILLIAM RIPPLE (OregonStateUniversity):

For example, the wolves are on the ground 24/7, and behaviorally are very different than human hunters.

HIRSHON:
But reintroducing wolves to an area, as was done inYellowstone National Park, has been shown to restore many trees and plants to healthier numbers.  I’m Bob Hirshon for AAAS, the Science Society.

Wolves chase an elk in Yellowstone National Park. (Doug Smith/National Park Service)

Baboons’ word processing skills.  I’m Bob Hirshon and this is Science Update.

Baboons can’t read, but they can learn to recognize words.  This according to researchers inFrance, including cognitive psychologist Jonathan Grainger ofAix-MarseilleUniversity.  They trained baboons to distinguish real English words from thousands of nonsense letter combinations.  With enough practice, they were even able to spot words they’d never seen before, more often than not.  Grainger says this suggests that we, too, may recognize words on a level that goes beyond sound and meaning.

JONATHAN GRAINGER (Aix-Marseille University,France):

Maybe we use letters as well to identify words, because we’re actually mimicking what we’re already very good at anyway, which is basic visual object identification.

HIRSHON:
In other words, we may see words the way we see tables, cars, or faces – as combinations of parts that make sense in some arrangements, but not others.  I’m Bob Hirshon, for AAAS, the science society.

With training, baboons can learn to discriminate words from non-words. (Photo courtesy of J. Fagot)

Naming the bug, picking the drug.  I’m Bob Hirshon and this is Science Update.

Many disease-causing microbes are resistant to antibiotics.  But confirming which drugs will work can take days.  Now, Harvard Medical School microbiologist Deborah Hung’s team is developing a single test that can identify a pathogen and size up its weaknesses.

DEBORAH HUNG (Harvard Medical School/Mass. General Hospital):
Long before a bacteria will grow or die in the presence of an antibiotic, there’s much earlier changes that happen to the cell. One of those very very early changes is actually the cell’s response to the stress and the shock of a toxic drug it’s being exposed to.

HIRSHON:
That stress is detectable in RNA – genetic material that can also be used to identify the bug.  Hung’s team tested the technique on bacteria like E. coli and tuberculosis, as well as viruses, yeast, and parasites.  Now they’re working to make the test faster and more sensitive.  I’m Bob Hirshon for AAAS, the Science Society.

Penguins on thin ice…I’m Bob Hirshon and this is Science Update.

The Emperor Penguin is Antarctica’s most iconic animal, yet until now, no one really knew how many of the flightless birds live there. Scientists from a consortium of research institutions have teamed up to better estimate their numbers using satellite images. Ecologist Michelle LaRue of the University of Minnesota explains.

MICHELLE LaRUE (University of Minnesota):

What we were able to do is basically train the computer to tell the difference between what we tell it is a pixel of Emperor Penguin vs. a pixel of guano vs. a pixel of ice.

HIRSHON:

The new satellite-based analysis estimates the population at around 600,000 birds, nearly twice the number counted in previous ground-based surveys. LaRue says the technique could be used to estimate other animal populations on the world’s most remote and inhospitable continent. She adds that having an accurate count will allow researchers to track the animals’ response to climate change. I’m Bob Hirshon, for AAAS the science society.

Emperor penguins on the sea ice close to Halley Research Station (British Antarctic Survey)

Researchers teach a computer to distinguish between pixels of guano, penguins and ice. (Digital Globe)

Tiny particles that pack a punch. I’m Bob Hirshon and this is Science Update.

Doctors have no shortage of compounds that kill cancer cells. The problem is that they’re also toxic to healthy tissue. Now scientists report in the journal Science Translational Medicine that they have developed a kind of microscopic capsule, or nanoparticle, that releases anticancer drugs into tumors, but not into healthy cells. If they prove safe and effective in humans, the nanoparticles will allow doctors to safely prescribe higher doses of chemotherapy medicine with fewer side effects.

And, in the same journal, scientists report new findings on Parkinson’s Disease patients who have gotten fetal stem cell therapy to boost levels of dopamine in their brains. They report that the therapy relieved motor symptoms, like tremors and difficulty walking. But the patients still need additional therapy for other symptoms, like anxiety and insomnia, which were unaffected by the boosted levels of dopamine. I’m Bob Hirshon, for AAAS, the science society.

Prehistoric raindrops.  I’m Bob Hirshon and this is Science Update.

Believe it or not, some fossils contain impressions of raindrops that fell billions of years ago.  Astrobiologist Sanjoy Som, now at NASA-Ames Research Center, used them to study the early Earth’s atmosphere. He explains that if the air was denser back then, raindrops would have fallen more slowly.

SANJOY SOM (NASA-Ames Research Center/University of Washington):

And thus the raindrop impressions would be smaller.  Versus if the air pressure was thin, then the drops would be falling faster, and the imprints would be larger.

HIRSHON:
While at the University of Washington, his team compared the fossilized raindrop impressions to new ones, which they made under precise conditions in the lab.  Their work suggests that the air pressure back then was much closer to today’s than previously thought. Som says comparing conditions on the young Earth to the present may help us make predictions about planets beyond the solar system.  I’m Bob Hirshon for AAAS, the Science Society.

A meerkat sits on rock covered in fossil impressions of raindrops. (Wlady Altermann/University of Pretoria)

Self-healing plastics…I’m Bob Hirshon and this is Science Update.

Plastic has transformed modern life, but it’s not known for its durability. Now, researchers at the University of Mississippi have designed a type of plastic that not only senses when it’s been damaged, but repairs itself. Materials scientist Marek Urban and his team have added tiny molecular bridges to the chemical chains that make up plastic. If the plastic is scratched, these bridges change color, alerting the user.

MAREK URBAN (University of Mississippi):

And upon exposure to visible light, the color changes back to neutral and the material is being self-healed.

HIRSHON:

He says the technology has a broad range of possible applications, from refreshing your scratched cell phone to improving aircraft safety.

URBAN:

From an environmental point of view you’d like to have more sustainability; from a safety point of view you would like to have materials that would self-repair upon mechanical damage.

HIRSHON:

I’m Bob Hirshon, for AAAS, the science society.

Click here to view a video of the self-healing process (clip courtesy of Marek Urban/University of Mississippi)

Setting the tone in music … I’m Bob Hirshon and this is Science Update.

Music can convey both happy and sad emotions. Neurobiologist Daniel Bowling and his colleagues at Duke University think music may share tonal properties with speech that express emotion in similar ways. Bowling says when people are sad, their tone of voice varies less, sort of like this, than when people are happy, sort of like this. His team found the same held true in both Western and South Indian music.

DANIEL BOWLING (Duke University):

When you have sad music you have small jumps between tones…

[Sad Raga]

When you have happy music you have large jumps between tones …

[Happy Raga]

And the same is true of speech.

HIRSHON:

He adds that this may be a universal phenomenon, allowing people to tell the difference between sad and happy music wherever it’s from. I’m Bob Hirshon, for AAAS, the science society.

Raga Shree recital to Krishna and Radha, Ragamala paintings, 19th century (Smithsonian Freer Sackler Gallery of Art/Wikimedia Commons)

A new look at self-diagnosis.  I’m Bob Hirshon and this is Science Update.

More and more people are using online symptom checkers to decide whether to see a doctor. But according to Arizona State University psychologist Virginia Kwan, the way the symptoms are listed on the website can affect their decision.  Her team found that when common symptoms, like headache and fatigue, were grouped consecutively, people felt they were more likely to have the illness in question.

VIRGINIA KWAN (Arizona State University):

When you look at those symptom checklists, and you say “oh, I have this, I have this, I have this,” it’s more likely to feel, oh maybe their medical risk is higher.

HIRSHON:
However, alternating common symptoms with rare ones, like a lump on the neck, made people less worried.  The effect was strongest for relatively short lists.   But Kwan says that medical websites may want to tailor their symptom lists for each illness, depending on whether it’s often missed or tends to attract unfounded worry.  I’m Bob Hirshon for AAAS, the Science Society.

Popular websites that allow you to diagnose yourself based on a list of symptoms may cause unnecessary worry, depending on how the symptoms are listed. (Jupiter Images)

The mystery of the yellowed paintings. I’m Bob Hirshon and this is Science Update.

Just as iron mixes with oxygen to form rust, fiber in paper bonds with oxygen to form compounds called chromophores. These are what make old paper documents and artwork look yellow. Now, in the journal Physical Review Letters, scientists finally describe the chemistry of the paper-yellowing perpetrators. The discovery could lead to new techniques to restore antique papers and artwork.

In other art-related news, many Vincent Van Gogh paintings depict showy sunflowers with multiple rows of yellow petal-like florets around the outside. Common sunflowers have just one row. Now scientists report in the journal PloS Genetics that they’ve found the gene responsible for the flashy flowers.  Understanding the genetic basis for this trait could help scientists develop new varieties of the plant optimized for seed production or ornamental gardening. I’m Bob Hirshon, for AAAS, the science society.

Vincent Van Gogh often painted sunflowers, as depicted in this painting by Paul Gauguin. (The Yorck Project/Wikimedia Commons)

Pitching a candidate…I’m Bob Hirhson and this is Science Update.

HIRSHON:

All other things being equal, people may be more likely to vote for political candidates with lower-pitched voices than higher-pitched voices. This according to Duke behavioral ecologist Rindy Anderson. She and her colleagues recorded both women and men saying:

SIMULATED CANDIDATE:

“I urge you to vote for me this November.”

HIRSHON:

The researchers digitally manipulated the recordings, making them sound slightly higher and slightly lower in pitch than normal.

SIMULATED CANDIDATE:

“I urge you to vote for me this November.”

Then they had volunteers listen to the voices and decide which version of the simulated politician they would rather vote for.

RINDY ANDERSON (Duke University):

We found that both male and female listeners voted more often for the lower-pitched version, whether it was a male candidate or a female candidate.

HIRSHON:

Anderson says this jibes with other studies suggesting that whether or not it’s deserved, deeper voices command more respect. They plan to test the findings in real elections later this year. I’m Bob Hirshon, for AAAS, the science society.

A voter's choice is influenced by many factors. (Tom Arthur/Wikimedia Commons)

An anti-cancer antibody…I’m Bob Hirshon and this is Science Update.

White blood cells destroy cancer cells by engulfing, or “eating” them. But a protein called CD47 acts as a “don’t eat me” signal, allowing tumor cells to grow. Now, Stanford University School of Medicine researchers have developed an antibody to CD47 which blocks that signal. To test its effect on cancer, they transferred ovarian tumors from women to mice. Biologist Irv Weissman led the research.

IRV WEISSMAN (Stanford University School of Medicine):

Within just a couple of months they had a signal from the cancer that was 30,000 times more intense than from the abdomens of the mice that had been treated with the antibody to the “don’t eat me” signal. That is, we cured the animals.

HIRSHON:

What’s more, the antibody either shrank or destroyed a wide variety of tumors. He says the next step is to test the safety and effectiveness of the antibody in human clinical trials. I’m Bob Hirshon, for AAAS, the science society.

A protein called CD47 promotes tumor growth by telling the immune system not to attack it. (Pleiotrope/Wikimedia Commons)

Sugar-free carnivores…I’m Bob Hirshon and this is Science Update.

While humans and most other animals crave sweets, many carnivores are sugar-blind. A new study reports that many species in the order Carnivora have accumulated mutations in their sweet taste receptors that destroy their ability to enjoy sugary foods. Biologist Gary Beauchamp of the Monell Chemical Senses Center and his colleagues already knew that all cat species lack sweet taste receptors. Now, DNA analysis reveals that similar mutations in species such as harbor seals and spotted hyenas have also wiped out their taste for sweets.

GARY BEAUCHAMP (Monell Chemical Senses Center):

It was startling to find that this was happening time after time after time independently.

HIRSHON:

But these animals do have well-developed taste receptors for amino acids, the key ingredients of meat. On the other hand, giant pandas, which also belong to the order Carnivora, but subsist almost exclusively on bamboo, have lost their ability to taste amino acids. I’m Bob Hirshon, for AAAS, the science society.

The spotted hyena, like many other carnivores, has lost its sweet tooth. (Marcel Oosterwijk/Wikipedia)

Antibiotics and asthma.  I’m Bob Hirshon and this is Science Update.

Kids who take antibiotics before the age of one are more likely to develop asthma.  A new study in mice at the University of British Columbia suggests that’s no coincidence.  Microbiologist Brett Finlay and his colleagues gave the mice one of two antibiotics: vancomycin or streptomycin.

BRETT FINLAY (University of British Columbia):

Andhat we found is that vancomycin, but not streptomycin, caused a profound increase in the amount of asthma in these animals. And what also was really interesting is that it only worked if you gave the antibiotics to these mice when they’re really young, basically right after birth.

HIRSHON:
Finlay says that the two drugs kill different types of gut bacteria, some of which may protect us from asthma as the immune system develops.  It’s part of a growing awareness that the bacteria in our bodies play a key role in keeping us healthy.  I’m Bob Hirshon for AAAS, the Science Society.

Antibiotic use in babies has been linked to an increased risk of asthma. (Jupiter Images)

Introducing the periscope camera. I’m Bob Hirshon and this is Science Update.

Researchers have demonstrated a camera that take pictures around corners. In the journal Nature Communications, they describe the use of a high-speed laser that can bounce light off even non-reflective surfaces, like walls and floors. Some of the light finds its way around the corner into a neighboring room and bounces back out again, where a sensor in the camera detects it. Software analyzes the reflections to recreate any three dimensional objects in the room. Future versions of the camera could let firefighters look for people trapped in buildings, or let police scan a room before entering.

In other news, Virginia Tech engineers have designed RoboJelly, an underwater robot that propels itself like a jellyfish, and gets power directly from hydrogen in the water. The robot is built using shape-memory alloys that can flex, and then return to their original shape. I’m Bob Hirshon, for AAAS, the science society.

A new frog in New York.  I’m Bob Hirshon and this is Science Update.

A previously unknown frog species has been found in the exotic forests of New York City.  It’s a type of leopard frog, with an unusual mating call that captured the attention of Rutgers grad student Jeremy Feinberg, when he was in the woods on Staten Island.  That led to genetic tests at the University of California, Los Angeles, in the lab of evolutionary biologist Brad Shaffer.  Shaffer says the frog’s known range is the New York metro area.

BRAD SHAFFER (University of California, Los Angeles):

As far as we know, it’s the immediate area right around New York City.  The largest population that we know of at this point is on Staten Island, and it’s right in the surrounding areas in New York and New Jersey.

HIRSHON:
The true range may actually be larger.  Shaffer says the frog hid in plain sight because it looks like other leopard frogs.  But he says it’s clearly genetically distinct, and in at least one area, lives among another species of leopard frog without interbreeding. I’m Bob Hirshon for AAAS, the Science Society.

The new, unnamed leopard frog species was discovered in the wilds of Staten Island. (photo courtesy of Rutgers University)