ScienceBlogs Channel : Brain & Behavior

Wolves Are Smart, but Dogs Look Back [The Thoughtful Animal]

Jason G. Goldman none@example.com — Tue, 31 Aug 2010 11:30:00 -0500

Dogs are pretty smart. They can have huge vocabularies, they can infer meaning in the growls of other dogs, and they can effortlessly figure out if other dogs want to play or fight with them. But their intelligence might be limited to the social domain; indeed, while they outperform chimpanzees in social tasks, chimpanzees outperform them in many other tasks. And they might have developed their impressive social skills as merely an accident of natural and artificial selection.

Previous research has shown that dogs can use lots of different forms of human communicative signals to find food, and they can also inform humans of the location of hidden food, by looking back and forth between that human and a second location. But what is it about dogs that allows them to comprehend and invoke human social communication?

Hungarian canine cognition researcher Adam Miklosi has written that "the genetic divergence of the dog from its ancestor was [presumably] accompanied by important behavioral changes that could have a genetic basis because of a selection pressure for dogs that were able to adapt better to the human social setting." If that was the case (and it probably is), then it follows that while some natural variation in performance on a given task requiring the use of human social communicative cues may be seen in wolves, it should be a lot stronger in dogs. Comparing wolves and dogs is the obvious way to address this question, but wolves and dogs differ both in genetics as well as in environment. While most dogs are raised in houses as pets, most wolves live in the wild, or in zoos, or occasionally in conservation parks. Adam Miklosi and colleagues, of Eotvos University in Budapest, took advantage of a very unique situation. Thirteen wolves were hand-raised and socialized in human homes, just as dogs would be. By raising both dogs and wolves similar contexts, the effects of rearing environment can be minimized, allowing the researchers to infer that differences in behavior are more likely due to genetic differences.

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Editor's Selections: Psychedelic Drugs, Narcissism, Cephalopods, and Friendship [The Thoughtful Animal]

Jason G. Goldman none@example.com — Tue, 31 Aug 2010 11:05:00 -0500

Here are my Research Blogging Editor's Selections for this week:

"Distorted perceptions and an altered state of mind: two reasons why psychedelics have always attracted not only fascination, but also controversy for decades." Noah Gray at Nature Blogs has curated a mini-carnival of sorts centering around a new paper called "The neurobiology of psychedelic drugs: implications for the treatment of mood disorders." Included are posts by Mo at Neurophilosophy, the Neuroskeptic, the Neurocritic, and Vaughan of Mind Hacks. (Note: Only Neuroskeptic's and Neurocritic's posts are indexed by Research Blogging, but all are being included for completeness.)
John M. Grohol at World of Psychology tells us that Narcissistic College Students Spend More Time on Facebook.
Mike Lisieski of Cephalove concluded a short series about octopodes with The Case for Cephalopod Consciousness.
At the Mind Matters blog, David Berreby explains Why A Good Friend Has the Same Effect As a Warm Fire.

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The secret history of psychedelic psychiatry [Neurophilosophy]

Mo none@example.com — Mon, 30 Aug 2010 12:45:44 -0500

This post is part of a Nature Blog Focus on hallucinogenic drugs in medicine and mental health, inspired by a recent Nature Reviews Neuroscience paper, The neurobiology of psychedelic drugs: implications for the treatment of mood disorders, by Franz Vollenweider & Michael Kometer. This article will be freely available, with registration, until September 23. See the Table of Contents for more information on this Blog Focus, and read the other blog posts:

Update: I summarize all four posts in this article for The Guardian, and there's more coverage of the Blog Focus at 3 Quarks Daily, The Atlantic, Boing Boing and The Great Beyond.

___________________________

ON August 15th, 1951, an outbreak of hallucinations, panic attacks and psychotic episodes swept through the town of Saint-Pont-Esprit in southern France, hospitalizing dozens of its inhabitants and leaving five people dead. Doctors concluded that the incident occurred because bread in one of the town's bakeries had been contaminated with ergot, a toxic fungus that grows on rye. But according to investigative journalist Hank Albarelli, the CIA had actually dosed the bread with d-lysergic acid diethylamide-25 (LSD), an extremely potent hallucinogenic drug derived from ergot, as part of a mind control research project.

Although we may never learn the truth behind the events at Saint-Pont-Esprit, it is now well known that the United States Army experimented with LSD on willing and unwilling military personnel and civilians. Less well known is the work of a group of psychiatrists working in the Canadian province of Saskatchewan, who pioneered the use of LSD as a treatment for alcoholism, and claimed that it produced unprecedented rates of recovery. Their findings were soon brushed under the carpet, however, and research into the potential therapeutic effects of psychedelics was abruptly halted in the late 1960s, leaving a promising avenue of research unexplored for some 40 years.

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Nobody Ever Remembers Being a Cow [Uncertain Principles]

Chad Orzel none@example.com — Mon, 30 Aug 2010 10:40:02 -0500

There was a deeply silly New York Times article about "Past Life Regression" over the weekend:

In one of his past lives, Dr. Paul DeBell believes, he was a caveman. The gray-haired Cornell-trained psychiatrist has a gentle, serious manner, and his appearance, together with the generic shrink décor of his office -- leather couch, granite-topped coffee table -- makes this pronouncement seem particularly jarring.

In that earlier incarnation, "I was going along, going along, going along, and I got eaten," said Dr. DeBell, who has a private practice on the Upper East Side where he specializes in hypnotizing those hoping to retrieve memories of past lives. Dr. DeBell likes to reflect on how previous lives can alter one's sense of self. He, for example, is more than a psychiatrist in 21st-century Manhattan; he believes he is an eternal soul who also inhabited the body of a Tibetan monk and a conscientious German who refused to betray his Jewish neighbors in the Holocaust.

At least this is in the Style section, aka "Stuff Wealthy White People in the Northeast Like," (the hook here is that well-to-do doctors in Manhattan have gotten into this stuff) but still, this is a bit much. As silly as it is, though, this at least represents a small amount of progress in dippy New Age thinking-- they don't quote anybody "remembering" being somebody famous in a past life. At the same time, though, nobody "remembers" a past life where they were anything disreputable.

Which is kind of remarkable, given how this is supposed to work.

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Extra, Extra [The Thoughtful Animal]

Jason G. Goldman none@example.com — Sat, 28 Aug 2010 11:30:00 -0500

Welcome to the weekly linkfest, August 28 edition.

Science
Brian Switek writes about one of the fastest mammals on earth, the pronghorn, and the complex ecology it lives in. Of Pronghorns and Predators. It's an interesting look into the predator-prey relationships between wolves, coyotes, and pronghorns.

Another great post from Brian, in which he tells us about the mystery of the missing brontosaurus head.

Yet another human falls prey to the illusion of attention. The guys at The Invisible Gorilla explain why there is just no safe way to text while driving.

The dog-human connection in evolution. A long post, but well-worth the read, in which the author argues that "animal domestication is one manifestation of a larger distinctive trait of our species, the 'animal connection,' which unites and underwrites a number of the most important evolutionary advances of our hominin ancestors."

Some really cool videos of cephalopods from Mike Lisieski of the Cephalove blog.

Jump behind the fold for the rest!

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Silver Spoon Hyenas: Maternal Social Status Affects Male Reproductive Success [The Thoughtful Animal]

Jason G. Goldman none@example.com — Fri, 27 Aug 2010 11:00:00 -0500

Figure 1: A mother hyena with her cubs.

Early developmental experiences can have significant implications for the growth, behavior, survival, and reproductive success of an individual. In many species, one of the most important factors that affects an individual's early development is the maternal environment. However, mothers not only provide an environment for their offspring, but also half of their genes, making it difficult to separate the effects of nature and nurture when investigating developmental outcomes in the offspring. Moreover, because male mammals usually disperse from the social groups into which they were born, it is difficult to determine how the maternal environment might influence the reproductive success of sons.

In species with marked sexual dimorphism, such as the red deer (Cervus elaphus), male fitness is related to overall body size and fighting ability. In this case, it is somewhat obvious that a mother of high social status who is able to provide her sons with more resources will result in larger, stronger males. However, in species with less sexual dimorphism, in which male reproductive success is not determined on the basis of body size or fighting ability, it is not clear whether the social status of the mother provides any real benefit to the son, in terms of his future reproductive success. The spotted hyena (Crocuta crocuta) is one such species.

The spotted hyena is a large carnivorous species that lives in "highly structured, female-dominated social groups called clans," in which access to resources is determined on the basis of social status. For that reason, females of high status have higher reproductive value and success than low-status females. In these clans, females generally spend their lives in the group into which they were born, which daughters acquiring a position in the dominance hierarchy close to and below that of their mother. They retain their social status into adulthood, as long as they retain the support of a close female relative. By contrast, male offspring typically leave the clan into which they were born after some time, and immigrate into another clan. However, they do not bring their social status with them. Instead, they must start at the bottom of the social ladder, and as higher-ranking males emigrate to other clans, or die, their social status can increase.

While female reproductive success is ultimately based on the social status of the mother, male reproductive success is dependent on how well the males conform to the preferences of the females. Indeed, females have complete control over who gets to mate with them.

Given the particular features of the social structure of these hyenas, the mechanism by which maternal social status affects the reproductive status of the daughters is quite clear. However, what is less clear is whether the social status of the mother can affect the reproductive status of her sons, especially since his privileged status does not transfer with him to his new clan upon emigration. Previous research of juvenile hyenas raised by adoptive mothers found no evidence of direct maternal genetic effects on the social rank of adopted offspring at adulthood. If a hyena was adopted by a high-ranking mother, he or she retained the high status of the mother irrespective of genetics. Thus, direct genetic effects were ruled out, and the researchers turned to environmental mechanisms.

Using data from a fourteen year study of all members of eight hyena clans resident in the Ngorongoro Crater in Tanzania, a group of researchers from Germany and the UK tested whether maternal social status influenced a number of factors: (1) the growth rate of the suns during infancy and early childhood, (2) their likelihood of immigration into the optimal clan in terms of potential reproductive success, (3) their age at first reproduction, and (4) the duration of residency in the new clan after immigration. They also investigated whether females preferred to mate with sons of high-ranking mothers. Their overall finding was that maternal social status did significantly contribute to the reproductive success of sons. But how?

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Silver Spoon Hyenas? [The Thoughtful Animal]

Jason G. Goldman none@example.com — Thu, 26 Aug 2010 11:00:00 -0500

A fascinating new paper just came out in Nature Communications and I intend to blog it in the usual manner, but I thought I'd try something new first. Check it out:

The Research Question

...According to life history theory, mothers should invest in their offspring if this enhances offspring survival and fitness, and if the fitness benefit to mothers from increased offspring fitness exceeds the cost of their investment. Whether the maternal environment influences the fitness and reproductive value of sons is unknown in most mammals because male mammals usually disperse and, thus, few studies have matched maternal quality to the fitness and reproductive value of sons after dispersal. In the red deer (Cervus elaphus), a species with pronounced sexual dimorphism, in which male fitness is linked to body size and fighting ability, a privileged upbringing by a mother of high social status provides sons with fitness benefits during adulthood. Whether a privileged upbringing also provides fitness benefits to sons in multifemale multimale mammal societies in which male fitness depends on how well males conform to female mate-choice preferences rather than a male's fighting ability or body size is currently unknown.

The Main Finding
The reproductive success and evolutionary fitness of male spotted hyenas is affected by the social status of his mother.

What do you think could explain this finding?

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Editor's Selections: Visual Noise, Aplysia, and Psychopaths [The Thoughtful Animal]

Jason G. Goldman none@example.com — Tue, 24 Aug 2010 11:15:00 -0500

Here are my Research Blogging Editor's Selections for this week:

Livia Blackburne asks what something called "visual noise exclusion" has to do with dyslexia. She classifies the post as "intermediate-advanced," but it's a good concise explanation of this complicated research finding.
People have been studying learning in aplysia, the sea hare, for decades. Bjorn Brembs has studied this critter himself for 10 years, but never saw one in the wild, until a recent trip to San Diego. There may be a reason that aplysia can learn.
Christian Jarrett of BPS Research Digest is hunting successful psychopaths. What is a successful psychopath? "...Thanks to their superior self-control and conscientiousness, rather than landing in prison, they end up as company chief executives, university chancellors and Queen's Council barristers. Well, that's the idea anyway."

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To Hear A Mockingbird: The Plight of the Iguana [The Thoughtful Animal]

Jason G. Goldman none@example.com — Mon, 23 Aug 2010 10:00:00 -0500

Predator-prey interactions are often viewed as evolutionary arms races; while predators improve their hunting behaviors and their ability to sneak up on their prey, the prey improve upon their abilities to detect and escape from their predators. The problem, of course, is that there is a trade-off between maintaining vigilance - the attention necessary to be consistently aware of others in the environment takes quite a bit of physical and mental energy - and doing all the other things that an animal must do, such as finding its own food. As a result of this trade-off, many social species, especially mammalian and avian species, have developed alarm calls. Alarm calls are specific vocalizations that signal the presence of a danger in the environment to nearby conspecifics, and sometimes contain additional information about the type of threat or predator.

As we've discussed before, subsequent to the introduction of predatory birds, howler monkeys on Barro Colorado Island near Panama rapidly developed an alarm call specific for those birds that indicated the presence of an avian predator; something like "danger from above!" That is, they did not merely adapt an already existing alarm call to the new predator, they developed an entirely new one.

In certain cases, prey species have developed the additional ability to eavesdrop on the alarm calls of other species, gaining access to an additional source of information relevant to the presence of danger in the environment. This ability could be the consequence of a learned association between the alarm calls of another species and the presence of the predator, or it could be due to certain auditory properties common to the alarm calls of both species, and innate. More research is required to tease apart these possibilities. However, until recently, it was thought that the ability to identify and react to the alarm calls of other species was only possible in species that already had vocal communication. Several years ago, however, researchers from Princeton University observed this behavior in an unlikely species - a non-vocal reptile - the Galapagos marine iguana (amblyrhynchus cristatus).

Figure 1: The Galapagos Marine Iguana.

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Extra, Extra [The Thoughtful Animal]

Jason G. Goldman none@example.com — Sun, 22 Aug 2010 10:30:00 -0500

Here's your weekly round-up of fun and fascinating:

To start with, I did a 6-part series on numerical cognition and the development of math skills, here and at Child's Play:

1. The Developmental Origins of Numerical Cognition
2. What is Dyscalculia? How Does It Develop?
3. Developmental Dyscalculia Explained: Strategy, Memory, Attention
4. Numbers on the Brain: Neurobiology of Mathematics

For an evolutionary perspective, there were the two companion pieces this week here:

5. What Are The Origins of Large Number Representation?
6. The Origins of Small Number Representation

Science
From Lucas Brouwers, a good explanation of why the term "living fossil" just doesn't make sense.

Why did humans evolve the capacity to imagine alternatives to reality? From the NY Times Opinionator blog.

An awesome time-lapse video of plants. I promise, it's really cool. (via Colin Schultz)

And another time-lapse video, this time of the Perseid meteor shower. Except, there aren't many meteors. But it's really neat to see the stars rotate across the sky, and the planes

Does the status of the pet dog without the family structure depend on where you live? Interesting, but not sure I totally agree.

More behind the fold!

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Harvard found Marc Hauser guilty of misconduct, his lab claims he manipulated data [DrugMonkey]

DrugMonkey none@example.com — Fri, 20 Aug 2010 20:43:31 -0500

The ScienceInsider blog published a letter from Harvard's Dean of Faculty of Arts and Sciences which states that Marc Hauser was indeed found guilty of scientific misconduct under their investigation process.

it is with great sadness that I confirm that Professor Marc Hauser was found solely responsible, after a thorough investigation by a faculty investigating committee, for eight instances of scientific misconduct

None of this pushing it off on the hapless trainee anymore. He was to blame.

The Chronicle of Higher Ed published an accusation supposedly from a former lab member.

The research assistant who analyzed the data and the graduate student decided to review the tapes themselves, without Mr. Hauser's permission, the document says. They each coded the results independently. Their findings concurred with the conclusion that the experiment had failed: The monkeys didn't appear to react to the change in patterns.
They then reviewed Mr. Hauser's coding and, according to the research assistant's statement, discovered that what he had written down bore little relation to what they had actually observed on the videotapes. He would, for instance, mark that a monkey had turned its head when the monkey didn't so much as flinch. It wasn't simply a case of differing interpretations, they believed: His data were just completely wrong.

Certainly the dude was charismatic. And had a good media reputation. And Greg Laden thinks he's a great guy.

But he was also willing to fake data. The odds are good that he is a case of pushing a little too hard to demonstrate what he just "knew" a priori to be true. I saw a comment on him somewhere or other that referred to him as a master experimentalist. He was just sooooo skilled at putting together the experimental conditions in the right way to demonstrate...something. The assumption has to be that this is in contrast to others in his field that had more, shall we say, difficulty. Well, perhaps the reason his experiments were seemingly so brilliant, effortless and beyond the reach of mere mortal primatologists was because Hauser was making up data? Fudging it the whole way?

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The Meta-Aggregator [The Thoughtful Animal]

Jason G. Goldman none@example.com — Fri, 20 Aug 2010 13:18:46 -0500

Two important notes for today - the full link round-up, as per usual, will come over the weekend.

First, the meta-aggregator to end all aggregators. Go check out scienceblogging.org - a fantastic tool built by Anton Zuiker, Blogfather Bora, and Dave Munger. It's not perfect, but the whole thing was put together in just the last few days. So go check it out, and leave suggestions and recommendations on the site blog. Read about its origins and philosophy here.

Second, the first edition of the Carnal Carnival is up at A Blog Around The Clock, and the theme is poop. Also, make sure you're following the official twitter account @carnal_carnival so you can get updates. To see a list of upcoming or previous hosts and themes, go check out the carnival blog and click on the the appropriate tab.

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Illusions of bodily awareness adapted for the pub [Neurophilosophy]

Mo none@example.com — Fri, 20 Aug 2010 10:20:19 -0500

DO you think that you perceive your body and the world around you as they really are? If your answer to that question is "yes", then think again. Our perceptions are little more than the brain's best guess of the nature of reality, constructed from fragments of information it receives through the senses. This is demonstrated by visual illusions, which produce discrepancies between physical reality and what we see of it, and by illusions of bodily awareness, which distort the way we perceive our bodies.

Psychologists and neuroscientists have long used illusions to investigate the mechanisms underlying perception. This is usually done in a laboratory setting, using specially designed equipment and, in the case of visual illusions, sensory stimuli. Some illusions of bodily awareness can, however, be easily induced without an elaborate experimental set-up or complex images. You too can dazzle your friends by perturbing their bodily awareness, using nothing more than the items that are commonly found in pubs and bars. Continue reading to see how...

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The Origins of Small Number Representation [The Thoughtful Animal]

Jason G. Goldman none@example.com — Thu, 19 Aug 2010 10:15:00 -0500

Earlier this week I wrote about the developmental and evolutionary origins of large number representation. A series of studies in human infants, monkeys, rats, and fish demonstrated that animals and humans spontaneously represent large (>4), abstract, approximate numerosities. Animals, human infants, and human adults, show the same ratio signatures (based on Weber's Law). Adult tamarins are on par with 9-month-old human infants. With age or training, discriminability becomes more precise, and the the critical ratio is reduced a bit. There is good evidence that the large number cognitive system is evolutionarily-ancient and non-verbal, and is innate.

What about for small numbers? Small numbers do not need to be counted or estimated; instead, they are subitized. Upon seeing a scene with a small number of objects you have a sudden, immediate sense of how many objects there are. This happens in parallel rather than serial- you do not need to count the items individually. Therefore, judgments made about displays of 1, 2, 3, or 4 items are rapid, accurate, and confident. As the number of items in the scene increases, judgments are increasingly less accurate and made with less confidence. Response times also increase, with an extra 250-300 milliseconds added for each additional item to be counted beyond four.

Previous work has demonstrated that animals have some pretty sophisticated numerical abilities, but often these experiments depended on a small number of highly trained captive animals, in highly artificial testing situations. What about spontaneous number representation in a population of non-trained free-ranging monkeys? Or human infants?

Cayo Santiago is a small island off the coast of Puerto Rico that is home to approximately 1,000 free-ranging rhesus macaques living socially. The fact that these monkeys are able to thrive in social groups isolated from any natural predators makes them an ideal population to study, and since they are so used to humans on the island, it is relatively easy to approach and work with them.

Figure 1: A rhesus macaque on the beach at Cayo Santiago.

The monkey study had two goals: (1) establish at least one natural context in which number is encoded spontaneously, and (2) establish the limits of this capacity, as a point of comparison for other animal studies, and for studies of human infants.

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Editor's Selections: Apologies, Fish Markets, and Addictions to Video Games and Cocaine [The Thoughtful Animal]

Jason G. Goldman none@example.com — Tue, 17 Aug 2010 17:52:32 -0500

Here are my Research Blogging Editor's Selections for this week!

At BPS Research Digest, Christian Jarrett asks what makes for an effective apology?
Krystal D'Costa of the Urban Ethnographer blog describes an afternoon at a fish market in New York City, and ponders the relationship of smell and memory.
The Neuroskeptic asks "Are you addicted to Starcraft? Do you want to get off Battle.net and on a psychoactive drug?" Is there really a drug that can curb your addiction to video games?
Dirk Hanson of Addiction Inbox discusses the chase for the genes implicated in cocaine addiction.

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What Are The Origins of (Large) Number Representation? [The Thoughtful Animal]

Jason G. Goldman none@example.com — Tue, 17 Aug 2010 09:30:00 -0500

This post considering the evolutionary origins of numerical cognition, specifically in terms of the approximation of large numbers, is meant as a companion to this week's series on the developmental origins of numerical cognition and developmental dyscalculia, at Child's Play.

What are the origins of number representation in the mind? Are there any innate building blocks that contribute to our understanding of mathematics and number, or must everything be learned?

Number is an important domain of human knowledge. Many decisions in life are based on quantitative evidence, sometimes with life or death consequences.

Figure 1: Fight or flight?

By now you probably have come to expect that I'll be arguing that there are several innate "building blocks" of cognition that give rise to more complex mathematics. To start with, what are some of the arguments proposed by the empiricists?
(1) Number knowledge is entirely conceptual - it requires seeing objects as belonging to sets;
(2) Number knowledge is abstract. You need to understand the similarity between 3 people, 3 objects, 3 sounds, 3 smells, 3 dollars, 3 seconds, 3 hours, and 3 years;
(3) It doesn't appear to be cross-culturally universal. Some cultures have more advanced mathematics than others; and
(4) babies and monkeys can't do long division.

Surely, humans have something unique that allows us to do things like multivariate regression and construct geometric proofs, however, but let's start at the beginning. I will hopefully convince you that there is an evolutionarily-ancient non-verbal representational system that computes the number of individuals in a set. That knowledge system is available to human adults and infants (even in cultures that don't have a count list), as well as to monkeys, rats, pigeons, and so forth.

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Rare Sharing of Data Led to Results on Alzheimer's [Science is Culture]

Adam Bly none@example.com — Mon, 16 Aug 2010 12:20:35 -0500

From the New York Times

The key to the Alzheimer's project was an agreement as ambitious as its goal: not just to raise money, not just to do research on a vast scale, but also to share all the data, making every single finding public immediately, available to anyone with a computer anywhere in the world.
No one would own the data. No one could submit patent applications, though private companies would ultimately profit from any drugs or imaging tests developed as a result of the effort.

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Did Dogs Gain Their Social Intelligence By Accident? [The Thoughtful Animal]

Jason G. Goldman none@example.com — Mon, 16 Aug 2010 07:30:00 -0500

I will be reposting some dog-related posts from the archives in the coming few weeks as I prepare for the course I'm teaching this semester on dog cognition. Please let me know if you find something inaccurate or unclear.

Domesticated dogs seem to have an uncanny ability to understand human communicative gestures (see here). If you point to something the dog zeroes in on the object or location you're pointing to (whether it's a toy, or food, or to get his in-need-of-a-bath butt off your damn bed and back onto his damn bed). Put another way, if your attention is on something, or if your attention is directed to somewhere, dogs seem to be able to turn their attention onto that thing or location as well.

Amazingly, dogs may be better at this than primates (including our nearest cousins, the chimpanzees) and better than their nearest cousins, wild wolves.

And so it was that biological anthropologist Brian Hare, director of the of Duke University Canine Cognition Center wondered: did dogs get so smart because of direct selection for this ability during the domestication of dogs, or did this apparent social intelligence evolve, in a sense, by accident, because of selection against fear and aggression?

Remember the Russian foxes? In that experiment, by selecting for tameness and against fear and aggression, a number of other seemingly unrelated traits began to express themselves in the domesticated foxes. They appeared to enjoy hanging out with humans. They sniffed and licked their caretakers. They wagged their tails when excited (remember this video?). Their tails got curlier and shorter. Their ears got floppier. Their skull-size (relative to body-size) increased. Their fur coloration patterns changed. They also showed evidence of physiological changes, such as in the pituitary-adrenal pathway.

Figure 1: Time for a picture of a dog. Some dogs are clearly smarter than others.

Hare and his colleagues pitted these two hypotheses against eachother. The "Selection for Communication" Hypothesis suggests that predicting and manipulating human behavior by reading human communicative signals (such as eye gaze or arm pointing) was explicitly selected in the domestication of dogs. Those dogs who were most skilled at comprehending such gestures were more likely to survive and reproduce. The "Correlated By-Product" Hypothesis predicts that the ability to read human communicative gestures was not directly selected for during the domestication of dogs. Instead, fear and aggression were selected against (which is the same as saying that tameness was selected), and as a result, those individuals with less stress, who had positive interactions with humans had the highest evolutionary fitness. Moreover, those same dogs, because of the "changes responsible for [their] high levels of tameness... were no longer constrained [by fear or disinterest, for example] in applying previously existing social problem-solving skills to humans" in interactions between the two species.

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Extra, Extra [The Thoughtful Animal]

Jason G. Goldman none@example.com — Sun, 15 Aug 2010 10:15:00 -0500

Science and Science Writing

Colin Schultz has committed science blogging! Science bloggers link more often to original research than do mainstream journalists. Not surprising, but good to know there's empirical research.

Hannah Waters of Culturing Science ponders the place of young science writers in the broader science writing ecosystem.

And in response, some good reminders about the business of blogging for n00b bloggers or journos. (via @edyong209)

As usual, another great piece from Bora in which he considers the relative benefits and consequences of being a part of a blogging cooperative versus a corporate network. A must read for any blogger!

An editorial from Nature: when blogs make sense.

More behind the fold!

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Supertaskers, The Act of Doing Nothing, and Other Recent Papers of Interest [Developing Intelligence]

Chris Chatham none@example.com — Fri, 13 Aug 2010 11:53:58 -0500

There are a few fascinating papers to come out recently that I won't have time to cover in detail, but which people may find interesting. References and abstracts after the jump:

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