Wednesday, 20 February 2013

Study Finds Dolphins Mimic Calls of Social Group

(BBC News, 20, Feb 2013) - Dolphins mimic the distinct whistles of their closest companions as a way of tracking them, according to researchers.

A team of marine biologists from the University of St Andrews studied the vocal signatures of the mammals.

Their findings suggested that dolphins mimic those they are close to and want to be reunited with.

It was already known that dolphins develop their own individual whistle which describes their identity.

The team of Scottish and American scientists analysed recordings from wild and captive dolphins to identify which animals copy one another's signature whistle.

The St Andrews researchers, working with scientists at the Walt Disney World Resort in Florida, found the mimicking was only present in mothers and their offspring, as well as in adult males who copied those they had long-term associations with.

The research involved a group of dolphins in Sarasota Bay, which has been studied since the 1970s. The animals are brought into captivity for medical tests once a year, which allowed the marine biologists to record and study their calls.

Dr Stephanie King, from St Andrews University, said: "Interestingly, this mimicking only occurs in animals who have strong social bonds.”

"It also only occurs when they are separated from each other, and this supports the idea that they want to reunite with the other animals.

"The next step is to do some experiments to play back their own calls and whistles to see if they can identify them."

The study also found that dolphins introduce slight changes into copies, avoiding confusion for the listener.

While vocal mimicking is found in other animals like song birds, the team believes dolphin calls offer an insight into the way complex language structures evolve.

Dr King said: "It is something we see in ourselves, but not in other animals.

"This could give us a real insight into how certain traits in language and communication have evolved."

Tuesday, 19 February 2013

Why Do Radiologists Miss Dancing Gorillas? - [News]

It's terminal I'm afraid.
Yes, seriously. 
You will slowly turn into a tiny dancing gorilla
(BBC Health, 16, Feb 2013) - There is something odd about this scan of a patient's lung. Have you spotted it yet? How about the dancing gorilla on the right?

It is not an everyday finding for radiologists, who are skilled at searching scans for tiny anomalies with potentially life-threatening consequences.

But in one study, more than three-quarters of specialist tumour spotters were caught out by the greatest anomaly of their career.

The out-of-place image was the brainchild of Dr Trafton Drew, a psychologist at Harvard medical school. He spent hours watching radiologists flicking through CT chest images and marvelled at their ability to detect tiny indicators of lung cancer.
"When I first saw radiologists searching through these images, they go through so fast and they detect these things that to me looked completely invisible and I just wondered how in the world are they doing this?"

He was inspired by a classic experiment from the 1990s, in which observers of a basketball practice failed to see a man in a gorilla suit walk across the screen. Dr Drew believed that radiologists, "the best searchers in the world", were good at detecting cancers but wondered what else they might be missing.
When we focus our attention on a narrow task we tend to miss other things and this effect, termed inattentional blindness, is exactly what the basketball observers were demonstrating. It turns out that there's a big difference between looking at something and perceiving it.

He asked radiologists to inspect CT chest scans for abnormalities called nodules, which could indicate lung cancer. Unknown to them, he had boldly superimposed a matchbox-sized image of a gorilla into some of the scans. When asked afterwards if they had seen a gorilla, more than 80% of radiologists and 100% of unskilled observers, said they had seen nothing - this despite the fact that the eye-tracking monitor showed that half the radiologists who did not see the gorilla had actually looked right at it for about half a second.
"Part of the reason that radiologists are so good at what they do is that they are very good at narrowly focusing their attention on these lung nodules. And the cost of that is that they're subject to missing other things, even really obvious large things like a gorilla."

Prof Daniel Simons, author of the original invisible gorilla study, explained that this effect is not unique to radiologists and reflects the way our attention system works.
"We're aware of only a small subset of our visual world at any time. We focus attention on those aspects of the world that we want to see.

"By focusing attention, we can filter out distractions. But in limiting our attention to just those aspects of our world we are trying to see, we tend not to notice unexpected objects or events."
It sounds dangerous that these expert radiologists might fail to spot something as obvious as a gorilla in your lung scan. But the radiologists were asked to search for lung cancer nodules alone and nothing else. Dr Drew thinks that if they had been asked to say more generally if there was anything wrong with the scans they would have been much more likely to find the gorilla.

"It shouldn't terrify you because they're looking for cancer and not gorillas," he said.
“Because attention is a finite quantity you have to make a decision going into the search about what's most important to you. “And for the radiologists in this experiment the gorilla is very different from the nodules they were told to search for. Dr Drew suggests that more of them might have detected an albino gorilla or, counter-intuitively, a smaller gorilla, closer to the size of the target nodules.

And it is not just gorillas. Drivers looking for cars at a junction can be blinded to cyclists, and baggage screeners at airports find it easier to focus on looking just for explosives or knives rather than trying to spot both.
Prof Nillie Lavie, an expert in attention at University College London, agrees. "On one hand it's worrying but on the other hand there are some mitigating circumstances. They were trained to look for particular features - size and colour. So it does not reflect at all on the radiologists' ability to report nodules. It reflects on their ability to report something unexpected. And that is something that could be trained."

Prioritising what we pay attention to has benefits. It allows us to ignore distractions and focus on the task at hand. But it's important to be aware of our limitations, says Prof Simons.
"I don't think we should be worried about these limits of attention, but we should be aware of them. We assume we will notice. And it's that mistaken belief that is dangerous. If you assume you will notice the gorilla, you won't take steps to make sure that you will."

"By knowing about these limits, we potentially could take steps to avoid them. For example, another radiologist could inspect the same images but without looking for a specific problem. If they don't have a really narrow goal, they might be more likely to spot unexpected problems."

Monday, 18 February 2013

A Monkey That Controls a Robot With Its Thoughts. No, Really. - [Video]

Can we use our brains to directly control machines -- without requiring a body as the middleman? Miguel Nicolelis talks through an astonishing experiment, in which a clever monkey in the US learns to control a monkey avatar, and then a robot arm in Japan, purely with its thoughts. The research has big implications for quadraplegic people -- and maybe for all of us. (Filmed at TEDMED 2012.)

Sneaky Canines: No Longer Out of Sight Out of Mind – [Article]

Om nom nom nom
(University of Portsmouth, 11, Feb 2013) - Domestic dogs are much more likely to steal food when they think nobody can see them, suggesting for the first time they are capable of understanding a human’s point of view.

Many dog owners think their pets are clever or that they understand humans but, until now, this has not been tested by science.

Dr Juliane Kaminski, of the University of Portsmouth’s Department of Psychology, has shown that when a human forbids a dog from taking food, dogs are four times more likely to disobey in a dark room than a lit room, suggesting they take into account what the human can or cannot see.

Dr Kaminski said: “That’s incredible because it implies dogs understand the human can’t see them, meaning they might understand the human perspective.”

This is the first study to examine if dogs differentiate between different levels of light when they are developing strategies on whether to steal food. It is published in the journal Animal Cognition. The research was funded by the Max Planck Society, Dr Kaminski’s former employer.

Dr Kaminski said: “Humans constantly attribute certain qualities and emotions to other living things. We know that our own dog is clever or sensitive, but that’s us thinking, not them.

“These results suggest humans might be right, where dogs are concerned, but we still can’t be completely sure if the results mean dogs have a truly flexible understanding of the mind and others’ minds. It has always been assumed only humans had this ability.”

The research is an incremental step in our understanding of dogs’ ability to think and understand which could, in turn, be of use to those who work with dogs, including the police, the blind and those who use gun dogs, as well as those who keep them as pets.

Dr Kaminski ran a series of experiments in varied light conditions. In each test, a dog was forbidden by a human from taking the food. When the room was dark, the dogs took more food and took it more quickly than when the room was lit.

The tests were complex and involved many variables to rule out that dogs were basing their decisions on simple associative rules, for example, that dark means food.

There is no evidence on how well dogs can see in the dark, but the results of this research show dogs can differentiate between light and dark.

Dr Kaminski said: “The results of these tests suggest that dogs are deciding it’s safer to steal the food when the room is dark because they understand something of the human’s perspective.”

Dogs’ understanding may be limited to the here and now, rather than on any higher understanding, Dr Kaminski said, and more research is needed to identify what mechanisms are controlling dogs’ behaviour.

In total, 42 female and 42 male domestic dogs aged one year or older took part in the tests. They were chosen only if they were comfortable without their owners in the room, even in complete darkness, and if they were interested in food. “Some dogs are more interested in by food than others,” Dr Kaminski said.

Previous studies have shown chimpanzees have a sophisticated understanding and seem to know when someone else can or can’t see them and can also remember what others have seen in the past. It is not known how sophisticated dogs’ understanding is in comparison. Many earlier research papers have found that, for dogs, a human’s eyes are an important signal when deciding how to behave, and that they respond more willingly to attentive humans, than inattentive ones.

Chemistry of Love: Owl Monkeys Shed Light on Evolution of Love - [Article]

(National Geographic, 13, Feb 2013) - It may not seem like monkey business, but emotional bonds in animals such as primates may have evolved into love as we know it.

Take owl monkeys, tiny tropical tree-dwellers that treat every day like it's Valentine's Day. A male and a female stick together as long as possible, never cheat, and never "divorce" their mates—extremely unusual behavior, even among people. (Also see "Male Monkeys Wash With Urine to Attract Females?")

Sometimes, though, young adult owl monkeys that can't find mates—monkeys that scientists call floaters—pick vicious fights with established pairs, eventually kicking one of them out.

Now, new research shows that the monkeys forced to take on new partners have fewer babies than owl monkeys that haven't been broken up, said Eduardo Fernandez-Duque, a biological anthropologist at the University of Pennsylvania in Philadelphia who led a new study on owl monkey relationships.

The results show how monogamy helps owl monkeys—and may even shed light on how human relationships evolved, said Fernandez-Duque, who has received funding for his work from National Geographic's Committee for Research and Exploration. (National Geographic News is part of the National Geographic Society.)

"Call it love, call it friendship, call it marriage—there is something in our biology that leads to this enduring, emotional bond between two individuals that is widespread among human societies," Fernandez-Duque said in a statement.

Only about 5 percent of mammals are monogamous, and the phenomenon most often arises when both parents are needed to raise offspring, as in the case of people.

With owl monkeys, fathers take on most of the childcare after a baby is born, relying on the mother only for milk. (See video: "Owl Monkey Fathers Know Best?")

But floaters—which Fernandez-Duque and colleagues first noticed in 2003 in Argentina's Chaco region (map)—can spell trouble in paradise.

Drawing on nearly two decades of observations of 18 owl monkey groups, the team discovered that pairs that stay intact produce 25 percent more babies than monkeys in severed pairs.

The exiled animal from those broken relationships, meanwhile, is usually injured and often dies.

Since the team studied more than 150 animals, "I felt very confident that what he was telling us is a real phenomenon—it's not a flash in the pan," noted Patricia Wright, who was one of the first people to study owl monkeys in the 1980s.

"He had the goods on the animals. I was really excited about that," said Wright, an anthropologist at Stony Brook University in New York.

Wright said she was personally pleased that the study reinforced findings that owl monkeys stay true to one another unless forced to separate.

"I knew that these little monkeys didn't fool around," she said.

Why monkeys that are broken up have fewer babies is unknown, though Fernandez-Duque suspects there's an emotional component. (See more pictures of all-star animal dads.)

Just as a man and a woman need time to get to know each other and form a deep connection, so do owl monkeys. So when a marauding monkey enters into a new relationship, there's a delay in mating—usually about a year, Fernandez-Duque  said.

In fact, pair bonding in monogamous animals, such as owl monkeys, may be "sort of evolutionary antecedent to love in humans," said Larry Young, a behavioral neuroscientist at Emory University in Atlanta and author of the new book The Chemistry Between Us: Love, Sex, and the Science of Attraction.

Young, who studies the brain chemistry of love and emotion, does most of his research on monogamous prairie voles.

Though human love is a rich emotion reflective of our advanced brains, he said, "the foundation of that emotion is very similar to the neuromechanisms that are causing the bond between these two prairie voles."

For instance, experiments have shown that if a vole loses its partner, the "widowed" animal shows depressive symptoms—measured by a lack of willingness to escape a dangerous situation.

According to Young, our brains are in the love seat, so to speak: The organs "have evolved the mechanism to produce an emotional attachment," he said.

That attachment is spurred by oxytocin—produced during intimate contact in both people and animals—and dopamine, which is responsible for feelings of exhilaration and happiness.

So, many splendored as it is, love, he said, "is really the result of a cocktail of chemicals."

Friday, 1 February 2013

Drinking Game Adds to Growing Support for Chimpanzee Culture

(LATimes, 30, January 2012) - Do chimpanzees have culture? It may depend on your definition of that slippery concept, but a new study using juice and soft straws shows that chimpanzees fill a basic requirement: They can learn new behaviours from one another.

Many researchers argue that few species, and perhaps none besides our own, have the capacity for culture – learned behaviours to spread across a population and down through future generations. (For humans, the definition would include things like beliefs, aesthetics, moral codes and knowledge, but given that chimpanzees lack language and can’t be asked about subjective thoughts, observable behaviours will have to do.)

Previous research had shown that wild chimps in separate communities would use sticks in different ways to fish for ants, a sign that such behaviours went beyond instinct. The new paper, published online Wednesday in the journal PLoS ONE, actually catches captive chimps in the act of learning such different tool uses.

The study presents "the first experimental evidence for chimpanzees' social transmission of a more efficient tool-use technique invented by a conspecific group member," according to the authors.

Researchers from Kyoto University in Japan and the University of Kent in England gave two groups of chimpanzees straws and put them in rooms with juice boxes mounted onto the wall. One group started using the 7-inch straws to dip into a hole in the juice box, while the other started using the sucking method (as humans would for a milkshake, or pretty much any other drink). 

Sucking juice through a straw was 50 times more efficient: A chimp could down 50 milliliters of juice in 30 seconds, while it would take their dipping peers 10 minutes to pull out a mere 20 milliliters.

When the researchers put a straw-sucker and a straw-dipper in the same room, they found that the dipper would quickly adopt this better, faster method if they closely observed it in action.

The demonstrating chimps didn’t seem to mind this up-close-and-personal style of learning. One video of the experiment shows a curious chimpanzee putting his face right up in the face of another chimp who was sucking the juice through a straw, then grabbing a straw of his own to try out this new, better method.

"Chimpanzees switch technique when not satisfied with their own," the study authors write. "Hence, necessity and opportunity appear to act as key prerequisites for cumulative cultural evolution."