You can find The Thoughtful Animal over at the new Scientific American Blogging Network!

Please remember to add or change the link to my blog in your blogrolls. The new URL is:
http://blogs.scientificamerican.com/thoughtful-animal/

If you use an RSS reader, such as Google Reader, the new feed is: http://rss.sciam.com/thoughtful-animal/feed/

In March 2010, I was invited to leave behind the relative obscurity of my wordpress blog for the warm community (and increased visibility) of ScienceBlogs. What a tremendous honor and opportunity that was!

But there comes a time in the life of every blogger when one must say goodbye to one’s current home, and move across town. Today is that day. Several months ago, when my friend and mentor Bora Zivkovic officially invited me to join the new Scientific American Blog Network, I simply could not refuse the offer.

So, starting today, you can find The Thoughtful Animal over at the new Scientific American Blogging Network!

Please remember to add or change the link to my blog in your blogrolls. The new URL is:
http://blogs.scientificamerican.com/thoughtful-animal/

If you use an RSS reader, such as Google Reader, the new feed is: http://rss.sciam.com/thoughtful-animal/feed (though it might be a day or so before this is operational)

As always, you can also follow me on twitter and Google+

So head on over, check out my intro post, and say hello.

And do be sure to check out the entire network as well! See you on the other side.

Update: Here is a link to the official press release.

Image: A white-bearded wildebeest running across edge of shallow Lake Makat, Ngorongoro Crater. Flickr/davidbygott.

Unfortunately, it was very, very hazy. The light was bad, everything was very washed out, and it was hard to get any real color. Luckily, I’ve gotten better and better (and had some good advice from friends) on doing some digital post-processing. The key, it seems, is to play to the strengths of the photo. Too hazy? Perfect for black and white.

Here is the before shot, as it was taken.

And here is the after shot, following some serious processing. I really like it – I think it evokes a feeling of New England, or of Herman Melville.

See the rest of the photoset on Flickr.

After a couple days of playing with it, I haven’t quite identified what it is for, or at least how I’m going to use it differently from twitter or facebook, but so far I am generally impressed – it’s easy, intuitive, and fast. It also allows you a level of selective privacy that – while possible to achieve – is very clunky on Facebook. It only took me 10 minutes on the web interface and another 10 minutes after downloading the Android app to figure out how it all worked. And Google+ is already far better integrated into the mobile user experience than Facebook is (though this is to be expected for a phone that runs Android).

The Huddle feature alone is worth the price of admission – which basically allows for group SMS. The Hangout feature is interesting as well – it is an amped up version of video-chatting, which uses your webcam and microphone to allow you to chat with up to 10 people at once. This is still limited by your own bandwidth – using my DSL connection at home, it was a bit choppy, but using a cable connection at a friend’s place, the feed was relatively smooth. I think there’s a lot of room for growth with Hangout, so while it isn’t particularly useful to me at the moment, I think it certainly could be. Leveraged properly, the tools available in Google+ could be extremely useful to bloggers. For example, by increasing the number of users from 10, but allowing the “host” to set certain users as “audience” or “participant,” Google Hangout could become something more like ustream; imagine bloggers being able to host live video podcasts, where viewers could participate via chat. With the proper tools to record the video, splice it together, and upload it to Youtube, Google Hangout could also allow people to create something similar to what bloggingheads does.

For the researcher, it is easy to imagine the convenience of being able to videoconference with collaborators, for example, while simultaneously editing a Google doc. Or private conversations conducted within a particular “circle” including only labmates or collaborators. If a member of a lab is out in the field, he or she could “call in” to a lab meeting using Hangout and share his or her latest findings, or to check in with the PI. I once gave a guest lecture to a class halfway across the country using Skype – while it was okay, there were still some technological limitations. If Google+ had been available at the time, those problems would have been trivial.

Beyond creative ways to use the tools, I remain unclear in terms of how exactly I’m going to use it on a day-to-day basis. To curate content (I do this with Google Reader already)? To engage with the wider sciblogosphere (I do this with twitter)? To keep up with old high school and college friends (I do this with facebook)? To be witty in more than 140 characters? With time, perhaps its use will become a bit clearer – after all, the product is only two days old. Given that Google+ is still in “field testing” operation, it will be interesting to see what they roll out in the coming days, weeks, and months.

For more:
Sheril Kirshenbaum’s review
Razib Khan’s review
Enrique Gutierrez’s review (recommended)

• To start us off this week, Neuroskeptic discusses a new study that attempted to use a computer to translate therapists’ notes into psychiatric diagnoses. Could it be that certain language used by therapists or their clients could predict the severity or duration of a mental illness? The study has problems, but it’s an interesting idea to consider, more generally. Machine-Readable Psychiatry.
• It is well known, according to Daniel Ocampo Daza of the Ego Sum Daniel blog, that “smokers tend to have a lower body-mass than non-smokers, and that smokers who quit have a tendency to gain weight.” Until recently, the mechanism behind the relationship of body-mass and nicotine addiction was unknown, but some new studies shed some light. Nicotine, Appetite, and the Brain.
• Here’s the next in our continuing coverage of new proposals for DSM-5. Dirk Hanson at Addiction Inbox discusses the proposal for the inclusion of a “problem gambling” diagnosis.

That’s it for this week… Check back next week for more great psychology and neuroscience blogging!

The LA Zoo wasn’t always in as nice a facility as it is now. The “old” LA zoo was built in 1912 and was in use until 1965, when it moved to its current location just a couple miles away in a different area of Griffith Park. It’s open to check out, and is adjacent to a picnic area. There are fenced off areas, but all the fences have giant people-sized holes in them. We thought of it more as: “enter at your own risk.”

From the picnic area you can actually approach and walk around what used to be the public viewing area of the bear enclosure.

There is also some sort of old barn, with what I think may have been enclosures for small primates in front of it.

We had about two hours of sun for some fantastic pictures, and then it got dark. And when it got dark, it got delightfully creepy – though, as my friend Enrique wrote, “Alas, sometimes, even the eeriest photos can’t capture just how wicked a place feels when you’re standing in the middle of it.”

For the rest of the photoset, here’s a slideshow, or just head over to my Flickr photostream.

You can check out Enrique’s as well – his photoset focuses a bit more on the heavy feeling of “urban decay” as you explore the abandoned zoo.

In my photoset, you can pretty much see all the structures that are left to see (there was a fire in the area that occurred well after the zoo was abandoned, that took out a few other structures), but there is definitely more there to photograph, so more visits are in order. But first: this old abandoned hospital.

If you’d like to go check out the old LA zoo, there are some decent directions in the user comments on its Yelp page.

Most animals, at some point in their day-to-day lives, face the same problem. After they’ve gone out in search of food, they need to find their way home. But some of the places where these critters live lack any real visual landmarks – like the open ocean or wide expanses of desert. Instead of relying on vision, some animals have developed the ability to use olfactory (scent-related) cues to aid in navigation. Seabirds can detect subtle changes in the smell of plankton in the air over hundreds of kilometers, and pigeons seem to use olfactory cues for finding their way home. It is known that some insects follow their noses (so to speak) to find food or a suitable mate. But Kathrin Steck, Marcus Knaden, and Bill S. Hansson of the Max-Planck Institute for Chemical Ecology wondered if the desert ants of Tunisia might use olfactory cues for homing.

It turns out that despite the visually featureless landscape, the salt pans of Tunisia actually have scent-related features. Variations in soil composition, breaks in the salt, and dead plants, all contribute different odors to the landscape. Do ants use the olfactory information in finding their way back to the entrance of their nests?

The researchers isolated four odor-producing compounds from various objects found in the vicinity of the ants nest. The first order of business was to verify that the odors were not particularly repulsive or attractive to the ants. The ants were then trained to forage for food in an 8 meter long trough, with the end of the trough that had been baited with food always downwind from the nest’s entrance. The experimenters applied one of the odors to the floor at the nest entrance, and re-applied the odor every 20 minutes, to ensure that the scent remained stable over time.

Would the ants learn to associate the specific odor with their nests? They tested them in troughs that contained (1) the same odor, (2) a different odor, (3) a mixture of four odors including the trained one, and (4) no odor at all.

Indeed, the ants learned to associate the specific odor they had been trained on with the nest entrance. They did the best under condition 1. And, they were able to pick out the trained odor from among the collection of four odors in the third condition. They were slightly less successful under condition 3 than condition 1, but way more successful than under conditions 2 or 4. In this figure, the trained odor condition is on the top, then the four odors condition, then the control condition is on the bottom. Each one is statistically significantly different from the others. The closer to the zero-point, the closer to home the ants wound up.

Pretty cool. But we’re not done yet. Oh no. First we put ants on stilts. Then we cut off their legs to create stumps. We blindfolded them and trapped them under boxes. But we have not yet antennectomized the ants. Until now.

What’s an antennectomy, you ask? I’ll tell you. Ants have two antennae. If you cut one (or both) of them off, you have performed an antennectomy. What are antennae used for? Smelling, of course.

So, think of it as a nose job for an ant.

Its a good thing ants don’t care much about their appearance. So much harder to perform a nose job if you’ve got two independent organs. “Doc, my one antenna is LONGER and THICKER than the other, and it’s HUMILIATING!”

So they trained the ants, as before, to forage in an open trough. One of four different odors was placed in each corner of an imaginary square adjacent to the nest entrance (in the figures below, this is represented by the four different letters). Since ants do not antennate the ground while walking, we can be sure that the ants are using their antennae for smell and not for taste.

The food was always aligned downwind from the nest as before, and the nest was never located at a spot of the highest concentration of an odor. Therefore the nest was gradient-specific, not odor-specific. Would the ants be able to use an odor gradient (as opposed to a single odor, as in the previous study) to find the nest? Do they perceive a sort of olfactory landscape? Are unilaterally antennectomized ants (ants with one antenna removed) at any disadvantage compared to intact ants?

In this figure, the little antenna represents the antennectomized ants. The other conditions represent intact ants. The left three conditions represent odor gradients; and the right two conditions are odors at a single spot (“point-source odors” as in the previous study). Going from left to right:
Condition 1: Intact ants on the training array did really well.
Condition 2: Intact ants with a right-left reversed testing array performed significantly worse than in training. This suggests that ants don’t just detect the overall array, but are sensitive to the position and strength of the odors within the array. That is, they track which odors are coming from the right and which from the left.
Condition 3: Antennectomized ants traveled five times longer than intact ants in condition 1, and did significantly worse.
Condition 4: This was basically a replication of the previous study. Intact ants trained to associate the nest with a single point source odor performed well. There was no significant difference between this condition and condition 1.
Condition 5: Antennectomized ants, when trained to associate the nest with a single point source odor performed well also! There wasn’t a statistically significant difference between these ants and the intact ants, when it came to point-source odors.

Taken together, this means that ants that have one antenna removed aren’t completely deprived of using odor cues (as condition 5 indicates). However, they are unable to use odor gradients in an array to locate the nest, as in condition 3. This suggests that ants smell in stereo.

What does it mean to smell in stereo? Well, humans smell in stereo thanks to our two nostrils, but this is hard to perceive. But humans also see in stereo, and this is probably a little more intuitive. Each of your eyes detects a slightly different image, and the visual cortex uses the slight difference between the two retinal images in order to construct a three-dimensional scene in your mind. Close one of your eyes, and you’ll realize that you have no real depth perception to speak of. Humans also hear in stereo, thanks to our two ears. If you covered one of your ears, you would find it very hard to determine the location of a sound. Thanks to the fact that sound waves reach each of your ears at slightly different times, your brain is able to figure out where in space a sound is coming from.

This is, incidentally, what filmmakers capitalize upon to make 3D movies. The projected image is two-dimensional, obviously. However, the projected image is composed of two slightly different versions of the same image. In old school 3D movies, the two images were colorized differently; one lens of the glasses filtered out red light, and the other lens filtered out blue light. The resulting images were projected onto your retina, and your brain put the two images together to construct a 3D image. New-school 3D movies work the same way, but are based on the light’s polarity, rather than color.

In much the same way, the two antennae of the desert ant (or your two nostrils) each have a slightly different olfactory “viewpoint” of the same olfactory “scene.” If you remove the input to one of your eyes, you don’t completely lose vision, but you lose the ability to perceive three-dimensional depth. Likewise, if you antennectomize the desert ant, it doesn’t completely lose olfaction, but it loses the ability to organize olfactory cues in three dimensions.

Steck, K., Hansson, B., & Knaden, M. (2009). Smells like home: Desert ants, Cataglyphis fortis, use olfactory landmarks to pinpoint the nest Frontiers in Zoology, 6 (1). DOI: 10.1186/1742-9994-6-5

Steck, K., Knaden, M., & Hansson, B. (2010). Do desert ants smell the scenery in stereo? Animal Behaviour. DOI: 10.1016/j.anbehav.2010.01.011

• Social hierarchies are pretty complicated to navigate…so why have them at all? Read about The Status Paradox at Psych Your Mind.
• ADHD well known, but how might an ADHD diagnosis interact with being an athlete? What should practitioners of sports medicine know about it? Bill Yates discusses this at his Brain Posts blog: ADHD and the Athlete.
• Do fish feel pain? It’s not a trivial question, especially if you are aware of what is on the dinner table. At the Fish Addict blog, grad student David discusses a new report on pain and nociception in fish.

That’s it for this week… Check back next week for more great psychology and neuroscience blogging!

You’ve probably had a conversation that goes something like this:
Person A: “My dog is sooooo amazing!”
You: “I mean, dogs are awesome and all, but what’s so amazing about this particular dog?”
Person A: “He just understands me. It’s like he knows what I’m thinking and what I need.”
You: “Do you think he’s just maybe responding contingently do your overt displays of emotion?”
Person A: “Listen, man, I’m telling you: my dog can read my mind!”

No matter on which side of this sort of argument you tend to fall, the question of whether or not domestic dogs can read human minds is an interesting and important one. More specifically, do dogs have a theory of mind? Can they take the perspective of a human?

Dogs show a wide range of “human-like” social behaviors. They respond appropriately to human body language and to verbal commands, and are capable of facilitating joint attention with humans. It some cases, their social skills, at least in terms of communication with humans, surpasses those even of chimpanzees.

Also, impressively, domestic dogs tend to perform particularly well in theory of mind experiments. The problem is that the experimental participants in these studies could potentially be responding to other sorts of contextual social or environmental cues when succeeding at theory of mind tasks, rather than relying on theory of mind skills per se. Ever the empiricists, some also argue that associative learning, rather then an innate theory of mind module, could account for dogs’ apparent theory of mind skills. If either of these sorts of arguments were indeed the case, then theory of mind would not strictly be necessary to explain these sorts of complex behaviors.

The best sorts of experimental designs to use in non-human animal theory of mind tasks derive from what I call the “Hare Task.” The Hare Task was originally designed for chimpanzees, and is in essence a food competition task. Two chimpanzees, one dominant and one subordinate, are placed at opposite ends of the testing area. Between them are two barriers, one clear (like a window), and one opaque. Just behind each of the barriers, on the side of the subordinate chimp, is a piece of food. In typical interactions, the dominant chimp always has first access to the food. However, the dominant individual can only see the food behind the clear barrier, while the subordinate individual can see both pieces of food.

The set-up looks something like this (source):

The idea is that if the subordinate chimpanzee has a theory of mind – if he (1) knows what the dominant individual does and does not see, and (2) assumes that the behavior of the dominant individual will be consistent with that knowledge – then the subordinate chimp should immediately retrieve the food behind the opaque barrier, and leave the food behind the clear barrier to the dominant chimp.

This sort of task can be easily modified to address slightly different questions for different animals, and recently in the journal Learning and Behavior, psychological scientist Monique Udell and colleagues from the University of Florida, Gainesville, have modified the Hare task to ask if domestic dogs can take the visual perspective of humans. Given that domestic dogs tend to do well on theory of mind tasks, Udell wanted to know if their success emerges due to a theory of mind, or whether their success can be explained by learning processes (such as classical or operant conditioning).

More specifically, some have argued that human-like social skills in dogs are the result of selection through the process of domestication, even if as a correlated by-product of the selection for or against something else. If these social skills are the result of domestication, then they are not simply the result of experience or learning. If this is true, Udell reasoned, then “all healthy populations of domestic dogs should be expected to outperform non-domesticated canids on human attentional-state tasks. Furthermore, this should hold true independent of the age, condition, home environment, or experience level of the dog under test.”

In order to investigate this question, Udell tested the ability of three different groups of canids, each of which varied on evolutionary origins or developmental experiments: pet dogs, shelter dogs, and human-reared wolves. All pets dogs were brought into the lab by their owners. The researchers were careful to exclude any shelter dogs that were owner-surrenders, and only tested strays who were comfortable around humans, but clearly had significantly fewer social experiences. The human-reared wolves were from Wolf Park, in Battle Ground, Indiana.

If dogs’ success at theory of mind tasks is the result of domestication, then both groups of dogs should outperform wolves, regardless of experience. However, if dogs’ success is the result of experience or learning, then the pet dogs should outperform the shelter dogs, and the human-reared wolves might outperform the shelter dogs as well.

In each of four conditions in this experiment, the dog or wolf was allowed to approach one of two researchers holding a piece of food in her hand. One of the researchers was designated the “seer,” while the second one always had her vision obstructed (“blind”). The “blind” researcher could be blind in one of four ways: back turned to the subject, holding a book in front of her face, holding a camera in front of her eyes, or holding a bucket over her head.

In each trial, the wolf or dog was kept 6 meters away from either of the two researchers by a third research assistant, with his or her back to the researchers. Then, in unison, both researchers would call the name of the dog or wolf (or, for the shelter dog, they’d say something like “here, puppy!”). The question was which researcher would the dog or wolf approach? Once the wolf or dog stayed within 1 meter of the chosen researcher for three seconds, the trial was concluded. In addition, the “seer” had to visually track the wolf or dog throughout the trial so that eye-contact could be initiated. If the subject approached the “seer,” he or she was rewarded with the food; if the subject approached the “blind,” even though she always held a piece of food in her hand, the subject was never rewarded.nd on every trial. Each dog participated in only two of the four possible conditions, though the wolves participated in all four experimental conditions (though they were distributed over the course of a year, to minimize the possibility of within-experiment learning). Altogether, each individual completed a total of ten trials.

Pet dogs and wolves had the best performance, with median performance levels of 9 out of 10 trials correct. Shelter dogs had the worst performance, with median performance levels of 7 out of 10 trials correct. For one condition, all three groups of canids performed significantly above chance: the back-turned condition. The results for the more nuanced conditions were, understandbly, more variable. For the book condition, pet dogs performed above chance, and significantly outperformed the shelter dogs and the wolves. While pet dogs performed above chance in the bucket condition, there was no significant group difference, and all three groups did similarly poor in the camera condition (no group performed, on average, above chance levels).

Udell and colleagues’ interpretation of the results is pretty straightforward, and is quite reasonable given the data (emphasis is mine):

The hypothesis that domestication is sufficient for dogs to engage in perspective taking is rendered problematic by the observation that dogs’ performance on these tests depends on the type of occluder used and on the life conditions of the canid. Furthermore, the success of wolves on one condition demonstrates that domestication is not essential for above-chance performance under all conditions. The alternative position is that domestic dogs and other socialized canids are not taking the mental perspective of the seeing or blind individual, but instead making a discriminative choice based on past reinforcement histories, in which certain human actions or orientations served as predictors of reinforcement upon approach. This hypothesis is consistent with the patterns of success and failure found in this study.

They reason that all individuals in the study, whether pet dogs, shelter dogs, or human-reared wolves, have experience approach individuals from the front or from the back, and all would have been equally likely to learn that it is statistically more likely to receive food from a human who is facing them than one whose back is to them. They argue that pet dogs would have had experience with humans reading books, and were therefore successful in that condition, while shelter dogs and wolves presumably had less or even no experience with book-reading humans on which to base their behavior. They explain the failure of even the pet dogs to respond appropriately in the camera condition to the possibility that the camera was simply too small of a visual barrier, making it less salient. To their credit, they also note that “on the other hand, humans can and do see through the lens of a camera and may even actively reinforce dogs or wolves for orienting toward them if they are the subject of the photograph. Therefore, the failure to discriminate between experimenters in this condition might even be considered the correct response.” When it comes to the bucket condition, it might seem surprising that even the pet dogs were unable to perform accurately. The researchers argue that each of the three groups of canids were unlikely to have had any experience interaction with humans who had buckets over their heads, and, as with the book, were unlikely to have learned the appropriate behavioral response to that stimulus.

The researchers conclude that domestication is not necessary, nor sufficient, to explain the performance of domestic dogs on theory of mind tasks. This is not all that surprising to me, though I would not take the position of the empiricist, and argue that their performance is more likely the result of learning. Rather, I am simply unsurprised that wolves have at least some rudimentary perspective-taking ability. Domestic dogs’ theory of mind is probably just a little bit sharper, or a little bit more fine-tuned due to experience, than that of wolves.

Further, Udell and colleagues hypothesize that “dogs’ ability to follow human actions stems from a willingness to accept humans as social companions, acquired early in [development], combined with conditioning to follow the limbs and actions of humans to acquire reinforcement.” My main problem with this line of reasoning is that this experiment doesn’t actually involve the movement of limbs, or any human actions. The only change in the body-state of the human researchers in the experiment is the tracking of the dog or wolf by the “seer,” so I’m not clear where any sort of action-related conditioning could enter into the dogs’ mental processing in the first place.

So, I suppose I’m just unconvinced with the larger argument put forth in this paper. Rather, I tend to agree with the notion that domestication has allowed for dogs to engage socially with humans in a way that wolves are not incapable of, but for which they are relatively unprepared. The fact that human-reared wolves had at least minimal success in this experiment does not surprise me, especially since they’re human-reared. The interesting finding, however, is the relative underperformance of pet dogs in the bucket and camera conditions: this is something, I think, that warrants further investigation. Why does performance in this task vary based on how the eyes of a human are occluded? It stands to reason that it ought to vary based on whether a human’s eyes are occluded or not.

It is also possible that some of the failures of the dogs and wolves in this experiment is simply due to the human presence. I’d be interested in seeing what would happen if the dogs and wolves were placed in a more competitive context, similar to the original Hare task. And, while we’re at it, how about comparing domesticated and undomesticated Siberian foxes? Now there are two populations of critters with highly controlled experiences, and precisely defined genetic relatedness.

Udell MA, Dorey NR, & Wynne CD (2011). Can your dog read your mind? Understanding the causes of canine perspective taking. Learning & behavior PMID: 21643852

Hare B, Call J, & Tomasello M (2001). Do chimpanzees know what conspecifics know? Animal behaviour, 61 (1), 139-151 PMID: 11170704

For more:
Wolves Are Smart, But Dogs Look Back
How Specific Are The Social Skills of Dogs?
Did Dogs Get Their Social Intelligence By Accident?

Dog photo by the author.

• “Most neuroscientists would subscribe to the sensorimotor hypothesis, according to which brains mainly evaluate sensory input to compute motor output,” writes Bjorn Brembs. But is it possible that the sensorimotor hypothesis is just the result of some laboratory artifacts?
• “What happens to a pig if it has a gene for autism?” This is the question that Neuroskeptic addressed earlier this week. Do Pigs Get Autism?
• What is it that makes an invasive species so successful at invading a new ecosystem? At NeuroDojo, Zen Faulkes asks if the brain could be involved. “Normally, we think of invaders as being able to turn out lots of babies, or having defenses that natives don’t, or all sorts of other factors. But could invaders be winning because they are smarter?”
• How are OCD behaviors formed? Historically, it was thought that there was no physiological basis for this mental illness, but this week at B Good Science, Ben Good discussed some new research that sheds some light on the biological etiology for OCD.

That’s it for this week… Check back next week for more great psychology and neuroscience blogging!