Archive for July, 2010
Next time you think about leaving your dog in the car on a hot day consider this:
While baking cookies in your car on a hat day may be cool in a weirdly nerdy sort of way, doing the same thing to your dog is not.
That whiff of a buddy’s just-back-from-lunch garlic, onion, tomato, salami and beer breath may kill your appetite, but to a mouse it provides a powerful incentive to grab a pizza and beer for himself.
As reported last week at Science News:
For rodents, any food smell combined with breath odor sends an irresistible “eat this” message to the brain, ScienceNews.org reported Thursday.
Carbon disulfide, a metabolic byproduct found in the breath of many mammals, stimulates specialized cells in the mouse nose, scientists report in the journal Current Biology.
These cells send a signal to specialized structures within the mouse brain that links an incoming odor with food that’s safe to eat, researchers said.
Olfaction arises from the interaction of several astonishingly complex subsystems. And they do a lot more than just detect odors. While some receptor systems help animals detect and decode a wide range of chemosensory input others affect and regulate specific kinds of behavior.
GC-D cells are a set of neurons in the main olfactory epithelium that detect specific hormones and urinary stimuli. Although GC-D cells were first identified back in the 1980’s, there’s no evidence that they play a role in odor recognition. So why are they present in some mammalian noses?
According to Science News:
Special nasal cells, called GC-D cells, seem to respond to the CS2 in rodent breath, experiments by Munger and his colleagues reveal. A mouse that smells cinnamon on a buddy’s breath will choose cinnamon-scented food over any other flavor, the researchers found. And it doesn’t even have to be another mouse: Cotton balls laced with a food odor and CS2 did the trick. But mice without working GC-D cells lost the ability to interpret this chemical message and they didn’t copy their compatriots’ food choices, the team reports.
The new work provides a molecular explanation for how these rodents learn what’s OK to eat, says neuroscientist Emily Liman of the University of Southern California in Los Angeles. For people and other primates, food preferences are mostly learned visually (or compelled via threats of no dessert). But for nocturnal creatures such as rodents, visual cues are limited. So it makes sense that there’s a scent signal, Liman says.
This safe-to-eat signal is so powerful that a mouse who has eaten poison will return for more if it catches a whiff of the poison on another mouse’s breath, says behavioral scientist Bennett Galef of McMaster University in Hamilton, Canada. “The strength of this social learning on food choice is huge,” says Galef, whose research revealed that mixing CS2 with rat poison drew four times as many rodents to the bait.
Humans and most other primates lack GC-D cells. Our eyes are as important as our noses in helping us decide what to eat. GC-D cells are present in dogs and many other mammals and, if mice are an accurate model, their noses play an important role in determining their food preferences.
We’ve known that carbon disulfide was important in helping mice and rats identify food sources for a long time but their link to the GC-D cells is a new discovery. Bennett Galef’s earlier research on carbon disulfide led to its widespread use as an attractant in rat poison. He wrote:
By signalling “safety,” CS2 increases the attractiveness of materials to which it is applied.
Carbon disulfide may increase the effectiveness of poison baits in ways that extend beyond simple enhancement of initial intake. Results of 4 recent sets of experiments indicate that experience with the smell of a diet, either on the breath of a conspecific, or in association with CS2, interferes with rats’ ability to acquire a subsequent aversion (bait-shyness) towards that diet.
The GC-D cells’ influence on food preference could help explain why every time a new pup or foster dog who eats poop stays at our place the rest of the pack starts eating poop again too.
The use of carbon disulfide as an attractant in rat poison may explain why dogs are attracted to eating it.
It could also explain why my dogs have no interest in a new Nylabone until I spit on it, and why Audie likes to sniff our breath after we eat.
And – because humans lack GC-D cells, it may also help explain why we don’t understand dogs’ great interest in sniffing urine, stale breath and feces.
A recent blog post by Jesse Bering over at Scientific American caught my eye today. Bering looks at a study published by Monique Udell, Nicole Dorey and Clive Wynne earlier this year in the journal Animal Behavior. Udell et al. claim to have demonstrated that stray dogs think about human social behavior and intentions in a fundamentally different way than our pet dogs do.
Bering recently returned from a trip to Sofia, Bulgaria and writes that:
Stray dogs are about common as squirrels there, and from what I saw, most of Sofia’s human population also has about as much interest in strays as Americans in the suburbs have in the squirrels living in their backyards. A June, 2010 estimate placed the figures at around 9,500 dogs running loose in the Sofia confines. So when you’ve got that many animals—even man’s best friend—in a relatively small, concentrated city (not to mention one with its own human homeless problems in the form of the ostracized Romanian Roma, or “gypsies”), mass desensitization is sadly inevitable. But this human-dog indifference is even more striking because it appears to be mutual.
I watched incredulously as the Sofia strays ambled casually down the sidewalks like proper Bulgarian citizens. They stepped aside politely for human pedestrians before continuing on their way, stopped patiently to look both ways before loping across frantically organized, crowded freeways, mingled with one another at storefronts and had their mangy coats tousled by the whooshing tires of passing commercial trucks while in the midday heat they slept quietly in tree-shaded gutters mere inches from the road. Most of these animals are multigenerational strays, which means that they are the offspring of strays who were the offspring of strays and so on, and on, for many breeding generations. Natural selection must work quickly indeed under such conditions: these are the descendents of the craftiest ancestral dogs of yesteryear Sofia, those who survived puppyhood without being crushed by some juggernaut and who managed to live long enough to pass on their wily natures to their offspring. Too much reliance on humans or interest in human behavior may well be maladaptive to these dogs’ overall genetic interests within this selective context, given the situation. I love my dogs, Gulliver and Uma, and they’re pretty smart as far as dogs go. But they wouldn’t last two minutes on the streets of Sofia.
The ability to read and correctly interpret human behavior is a vital skill if you’re a stray dog who wants to survive in an urban environment. The hordes of people who surround him are boon and a threat at the same time. A stray dog has to be able to judge whether a strange human’s intent is aggressive or benign in a nanosecond.
But while domestic dogs have been the focus of several studies on social cognition, feral dogs remain a resource for information that’s rarely been mined. Until recently, that is.
I wasn’t able to pull up a free copy of Udell et al.’s study and I’m too cheap to buy one, but Bering writes that:
Udell and her group in Florida, however, say that these impressive social cognitive abilities in dogs may not represent the “default” canine cognitive system. In their review of this literature on dog social cognition, the authors point out that:
The currently available data suggest that populations of dogs differing in [breeding] and in environmental and lifetime pressures might display different behavioral responses to the actions of humans. Despite this fact, the great majority of subjects in studies of the origins of domestic dogs’ human-compatible social cognition have been pet dogs living in human homes, with human-oriented working dogs representing the remainder of the subject pool.
In other words, Udell and her coauthors’ contention is similar to arguments made by many researchers studying human psychological evolution—that our ability to make claims about “human nature” are seriously limited by the fact that the data upon which such claims are made are derived almost entirely from middleclass American undergraduate students between 18-22 years of age and recruited from a psychology department subject pool. She’s basically arguing that existing social cognition research on Canis lupus familiaris has largely neglected large demographic swells of the species and therefore does not necessarily paint an entirely accurate portrait of this species’ natural (default) psychological stance.
Comparing feral dogs to pet dogs is a lot like comparing undergraduates to middle-aged suburban housewives – but… I think Udell et al. made a bigger mistake if they extrapolated data collected from truly feral dogs living in shelter environments to those living free on the street or, for that matter, to dogs in general. Feral dogs in shelter environments are like early Native Americans forced into confinement camps. Trapped in an alien environment they have little or not control over, they won’t respond in a way that’s normal for them, much less the species in general. While they may be an interesting group to study, their behavior is not characteristic of the population at large.
We’ll get back to that point later. Meanwhile, back at the lab Udell et al. administered two different pointing comprehension tests to dogs at an animal shelter. The goal of the study was to assess the relative importance of a dog’s life experience in shaping his ability to understand human pointing gestures. The use and interpretation of pointing and other indicative gestures are important because they can tell us a lot about an animal’s higher cognitive abilities.
Index finger pointing is an innate skill in humans but it’s not the only way we send and receive directional and attentional cues. We also do it by shifting our gaze, turning our heads and re-orienting the position of our bodies. Dogs don’t have fingers so they may need to learn to interpret finger pointing gestures. I believe, however, that dogs do have some innate skills in using and understanding other types of pointing gestures.
And indeed there is strong evidence they do. Bering writes:
Several years ago, Duke University psychologist Brian Hare and his colleagues reported some striking evidence showing that domestic dogs performed above chance on a variety of human-guided selection tasks—including studies in which human experimenters pointed to different objects in the room. At the time, these data were interpreted as showing that dogs have human-like social cognition allowing them to understand cooperative intent in humans. In fact, whereas tame wolves fail to score above chance in such studies, domestic dogs even outperform chimpanzees on similar pointing tests, suggesting that we may have more in common psychologically with dogs than with species for which we’re taxonomically (much) more closely related. This prompted Hare to argue that the co-evolution of humans and the domestic dog had created in the latter a genuine ability to reason about human mental states.
Some of our human understanding of pointing gestures develops over time. In very young children (babies and toddlers) pointing is used primarily as a request. These kinds of declarative pointing gestures are the human equivalent of what I refer to as the “That! That!” point in my dogs. It’s the nose and gaze aimed with laser beam intensity at an object of desire that is literally or culturally out of a dog’s reach. In a declarative point a dog will stare fixedly at the object for long periods of time. If the dog thinks his dimwit owner has missed (or is ignoring) the gesture, he may turn and give her a brief inquisitive (please?) or cross (hey dimwit, over HERE!) look before returning his attention to the object.
As a human child matures she will start to use pointing gestures to guide your attention to things she thinks you may find interesting. The indicative or “Hey, look at That” point is seen as a sign of an increased cognitive maturity in a child because its use indicates that the child is able to understand when others are and are not aware of something. That she has developed a theory of mind.
I believe that dogs (at least some of them) use indicative pointing gestures too. When Audie notices that one of our hens has escaped the back yard fence he’ll run to me with a very alert posture and work to catch my eye while stepping, dancing or making short darts to and then away from me. This “Timmy’s in the well!” attitude contrasts sharply with the still, fixated postures characteristic of a dog’s declarative pointing gestures.
Once he gets my attention Audie will lead me to the place where he found the lost hen (or dead raccoon or some other Thing of Vital Import) and use animated body postures combined with quick back and forth glances to direct my attention appropriately. The ability to use indicative and declarative gestures would imply that dogs have some ability to understand them as well.
Udell et al. wondered whether or not this ability to understand human pointing gestures is innate in dogs. Their thesis was that if stray dogs performed as well as pet dogs on pointing tests it would indicate the ability is innate. If they did not, some form of experiential learning is required to develop the skill.
The most significant findings from Udell’s studies were these. Although the strays performed above chance when the experimenter was kneeling on the floor and the tip of the experimenter’s finger was rigidly held 10 cm from the target can, unlike the domestic dogs in prior studies these strays failed to respond correctly to the pointing gesture when such an obvious physical cue was removed. On pointing trials in which the experimenter’s finger was 50 cm from the closest edge of the target container at full extension and then her arm was retracted back to a neutral position before the subject was allowed to make a choice, the strays’ performance fell to chance levels. This distinction is critical for the debate over whether domestic dogs have some semblance of theory of mind, because in the first instance at least, dogs may be using a simple behavioral heuristic such as “pick-the-box-closest-to-the-hand” that does not require human-like social cognition in which they are inferring cooperative intent.
The data shows that the shelter dogs tested displayed inferior skills at interpreting two basic human indicative pointing gestures. This would appear to indicate that there is at least some learned component involved in dogs’ abilities to interpret pointing gestures.
In an article titled “Ontogeny’s impacts on human-dog communication” Clive Wynne, Monique Udell and Katherine Lord discuss how they studied 6 to 24 week old puppies’ skills at interpreting three different human pointing gestures. They report that “In each case, the oldest dogs performed better on each point type than the youngest dogs.”
This provides additional evidence that these skills have an acquired component – but… a study strikingly similar to Wynne et al’s conducted by Tanya Behne, Malinda Carpenter and Michael Tomasello on human toddlers in 2005 produced, well… strikingly similar results. So it appears that we need to learn these skills too.
Udell et al. chose to study stray dogs from American shelters because they were interested in testing a population of dogs who hadn’t had a chance to learn human gestures in a home environment. But Wynne et al.’s work indicates that even spending a few months or even weeks in the company of humans who use pointing gestures meaningfully with them provides puppies with enough exposure to significantly improve their ability to understand these gestures. This leads me to wonder whether the dogs in Udell et al.’s study performed poorly because they were feral – or because there were in a highly stressful shelter environment. (Or maybe just because no human had ever communicated meaningfully with them before.)
Do feral dogs lack the ability to correctly interpret human body language? Perhaps those living in rural areas do, but when I watched the video of stray dogs at large on the streets of Moscow below, the first thing I noticed was how effortlessly they interpreted subtle cues from the people around them.
I also thought it was interesting (and a little depressing) that they displayed far better manners than most pet dogs do.
I think it would be a lot more interesting to test feral dogs at large in their natural environment using different kinds of indicative gestures. Finger pointing, gaze, head / facial orientation and body orientation gestures are used by humans (and dogs) to signal location and intent. Feral dogs need to be brilliant students of human behavior and intent to survive in urban environments and I wouldn’t be surprised if they performed significantly better than pet dogs at interpreting subtle cues – when tested in their natural environment.
It would also be interesting to study how being in the stressful environment of a shelter affects dogs’ performance at these kinds of tasks. The poor performance of the dogs in Udell et al.’s study may have been related more to the stressful environment they were tested in than their level of skill. If this is true it has important implications for shelter dog testing.
I’ve blogged here before about Daniel Pink’s ideas on motivation and how they may relate to dog training. Here’s an excellent video from RSAnimation on Pink’s thesis that treats, financial incentives and other extrinsic rewards are demotivating in tasks that require even rudimentary conceptual efforts.
If we believe that dogs are capable of rudimentary cognitive skills, perhaps it’s time for dog trainers and behaviorists to throw the narrow, outmoded obsession with Skinner’s quadrants – and all the hype and confrontation associated with them – into the recycling bin.
To recap this entire nutty situation, out of the blue the Delta Society (a non-profit organization that organizes and trains dog owners for volunteer visitations to nursing homes, hospitals, and similar) made the decision to ban all Pet Partners (certified pet owner/dog volunteer teams) from feeding their pet a raw meat diet. The decision, according to Delta Society, was based on scientific evidence that a raw meat diet causes the pet to shed (in feces) bacteria (such as Salmonella) that could put patients (those visited by Pet Partner teams) at risk. The Delta Society provided some clinical evidence (emphasizing the word some) to support their decision. Shocked and bewildered existing Pet Partners provided the Delta Society with a vast amount of opposing clinical evidence that showed dogs fed a kibble or can diet as well sheds (in feces) potentially risky bacteria (such as Salmonella). This opposing clinical evidence was ignored by the Delta Society. During the shocked and bewildered stage of this dilemma, it was discovered that a Purina Pet Food executive sits on the board of directors of Delta Society and the same Purina executive is applying for a patent that appears to seek control over all pet businesses involvement with pet charities. The Delta Society, despite the suspected connection, steadfastly denies that Purina Pet Food had any input into their decision to ban Pet Partners from feeding a raw meet diet.
Just when you think this situation couldn’t become more blatant bought and sold pet charity, I received an email from a former Pet Partner (an intelligent pet owner that made the educated decision to feed their pet a raw diet then ultimately decided the health of her pet was more important to her than her than following Delta Society’s new ban) sharing a nutty piece of information. She informed me that the new Delta Society Pet Partner banner (the harness type clothing that the dogs wear indicating they are a trained volunteer) now includes a Purina Pet Food logo. In other words, every Pet Partner will now be a walking advertisement for Purina Pet Food.
I understand that pets fed a raw (generally noncommercial) diet can shed bacteria such as Salmonella in their feces – but so do pets fed regular kibble diets. I would also hazard a guess that it is not uncommon for humans fed “normal” diets to shed potentially dangerous bacteria in their feces. Last time I checked – this is one of the reasons all hospitals require all staff and volunteers to practice good hygiene.
Given this information, one wonders why Delta has chosen to ban all dogs fed raw meat products from their program. But in an odd bit of inconvenient coincidence we find that Delta’s decision to ban raw diets occurred at about the same time that Purina – a major manufacturer of kibble diets signed on as a major financial sponsor of the group. Purina features an anti-raw diet “public service announcement” on their website. But Delta assures us that this had nothing at all to do with their decision.
Even though all Delta Pet Partners will now sport prominent Purina logos…
If that connection wasn’t eyebrow-raising enough, a new update from The Truth About Pet Food explains that Delta appears to be collaborating with Purina on the design of a particularly sleazy form of subliminal marketing cum social engineering:
Brenda Bax, Marketing Director for Purina Pet Food and Delta Society Board of Directors member has applied for a very unusual patent; “Methods for marketing corporate brands”. The patent Ms. Bax is seeking is basically a means for Big Corporations to work through animal charities (use animal charities) to develop a specific marking plan to pitch their products. Nothing new in marketing really, but what is puzzling and concerning is a pet food company wishing to patent a system where an animal charity works with a corporation for donations.
The Abstract of the patent Ms. Bax of Purina Pet Food…
“Abstract: Business methods are provided for marketing and increasing sales of corporate products or brands by collecting information about one or more animal welfare organizations, collecting information from one or more consumers about animal welfare, and processing the animal welfare organization information and the consumer information to design a marketing program executable by the corporation that enables the consumer to interact with the animal welfare organization.”
I am confused and concerned. Why would Purina Pet Food want to patent a marketing method associated with an Animal Welfare Organization? Is this patent application a concern to all Animal Welfare Organizations that do not currently work with Purina Pet Food? Does this patent provide Purina Pet Food control over all other corporations working with/donating to an Animal Welfare Organization?
Is/was Delta Society their first test market and the “wherein the animal welfare organization must meet a specified requirement to be a part of the marketing program” was the ban of pets fed a raw diet?
Marketing has become such an integral part of our lives that we tune most of it out. So companies with billion dollar budgets are constantly searching for new ways to sneak their message past our protective radar. In a world that is often characterized as being dominated by sleaziness – Purina and Delta appear to have taken things to an incredibly astounding new low.
You may be surprised to discover which is more likely to send you to the hospital…
Today’s post was inspired by a thought-provoking comment on FaceBook from Sarah Wilson who posted that:
Flexi lead has more, longer and more severe warnings for their product than say Glock by an extremely large margin.
This presented such a spectacularly delicious opportunity to pick on my least favorite dog training tool that I figured it couldn’t possibly be true. So I looked both documents up, and by golly she’s right. The Flexi lead’s product safety warning is over 1,400 words long. Glock’s is less than 250.
I understand that the number of words (or scary pictures) published in a product safety warning isn’t necessarily a fair indication of how dangerous an item is, but since is it’s no secret that I hate the ubiquitous retractable leash I decided to do a little research on accident statistics to see if I could turn up anything interesting.
The results of my search were absolutely jaw-dropping.
According to the Consumer Product Safety Commission (CPSC) 16,564 injuries associated with leashes required hospital treatment in 2007.
While CPSC doesn’t break the leashes involved down by type, based on a couple of decades spent obsessively watching people walk their dogs in all kinds of situations I very strongly suspect that the lion’s share of these injuries were caused by retractable leashes like the Flexi lead. And data provided by Consumer Reports appears to support my suspicion.
According to Consumer Reports:
The most common injuries reported were burns and cuts, usually sustained when the cord came in contact with skin as it rapidly paid out from the handle of a leash. Others occurred when the cord got wrapped around part of the owner or the dog.
The kinds of injuries described by Consumer Reports can only occur with retractable leashes like the Flexi lead. A good old-fashioned six foot long leather lead does not ‘pay out’ from a handle. It won’t give you rope burn and it doesn’t cut your hand when you grab it. The kind of leather leads favored by obedience competitors and skilled dog trainers are not likely to hurt you in day to day use. The same obviously cannot be said for retractable leads.
But how dangerous is a Glock?
The Center for Disease Control’s Web-based Injury Statistics Query and Reporting System (WISQARS) is an interactive database that allows the public to create customized reports of injury-related data. Because I think it is probably safe to assume that only a vanishingly small number of leash injuries are intentionally inflicted (and a quick google news search for garrotings committed with leashes turned up absolutely no results) I decided it would be most accurate to compare leash injuries to unintentional firearm injuries. Running the numbers I discovered that in 2007 15,698 Americans received unintentional non-fatal firearm injuries.
So there you have it. While no one is likely to actually murder you with a Flexi lead, based on 2007 data compiled by the Center for Disease Control – you are more likely to be seriously injured by a leash than by the unintentional discharge of a firearm.
Think about that for a minute.
A tool that millions of pet owners use every single day is as likely be involved in an accident that sends you to the hospital as a gun is.
To take this a step farther, let’s consider how many more unintentional nonfatal injuries might have been caused by Flexi leads than Glocks in 2007.
FlexiUSA reports an annual revenue of about $3,900,000. Leads typically sell for $15-20 each so let’s be conservative and divide that number by $10. That means that approximately 390,000 Flexi leads are sold in the US each year. We’ll assume that each lead lasts an average of five years putting approximately 1,950,000 Flexi leads in American hands.
According to Glock 2,500,000 Glock pistols have been sold in more than 100 countries over the last 20 years. The Small Arms Survey published by Graduate Institute of International and Development Studies in Geneva states that civilians own approximately 650 million firearms worldwide and Americans own some 270 million of them. So if Americans own, on average, 41.5% of all firearms let’s just assume that they also own 41.5% of all brands putting approximately 1,040,000 Glocks in American hands. If accidental gun injury statistics are consistent with brand that would mean that only 6,515 Americans were injured by the accidental discharge of Glock firearms in 2007.
So according to my estimate in 2007: 1,950,000 Flexi leads sent 16,564 people to the hospital (or about 0.85% of all users); and the accidental discharge of 1,040,000 Glocks sent 6,515 people to the hospital (about 0.6% of all users). This means that you are about 50% more likely to be seriously injured by a Flexi lead than an accident involving a Glock!
Of course it’s patently ridiculous to say that a Glock is inherently less dangerous than a Flexi lead. The real problem is that a frightening number of Americans have convinced themselves that mindlessly holding onto a plastic handle attached to a dangerously convenient retractable cord is a perfectly acceptable alternative for mindful dog training.
And thus we end up with a disturbing number of people who are the Flexi lead holding equivalent of this on the street:
To paraphrase Plaxico “If you see a Flexi lead you leave that motha fucka alone! You go get a dog trainer, you go get some training…”