lecture 2 - iSites by yurtgc548

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									The Cognitive Dog

Class 2: The Great Debate

Bruce Blumberg & Carolyn Barney
Harvard Extension School
Agenda for class

• Big apology about the reading!!!!!!


• Questions from last week


• Plan for next week


• The Brain Trust, Part 1.


• Great Debate
Plan for next week

• The behavior of wolves and wild canids


• Readings from course pack


  • Packard (2005) Wolf Behavior: Reproductive, Social & Intelligent


  • MacDonald et al (2004) Society
Introducing the Brain Trust, part 1.
The debate: the evolution of human-like social
skills in dogs?
A word to the wise

“we agree with one of our reviewers saying that the present state of this field does
not allow for scientific arguments on social cognition evolution” - Adam Miklosi &
Krisztina Soproni




   Miklosi, A. and K. Soproni (2006). "A comparative understanding of the human pointing gesture." Animal Cognition 9: 81-93.
Another word to the wise

Scientific work almost always needs to be seen through the lens of the
intellectual, social and funding context in which this work was done
Miklosi, A., J. Topal, et al. (2004). "Comparative social cognition: what can dogs teach us?" Animal Behaviour 67(6): 995.




                 A bit of a cottage                                                       Really about the evolution of
                                                                                          social cognition
                           industry                                                       Hungry
                                                                                          UK
Why?

• Evolution of social cognition in humans is a “hot” topic


• The argument is that dogs represent a really interesting animal model


   • Highly social


   • Presumably their behavior has been selected for success in the ecological
     niche of human-dog social groups.


   • Dogs “are enculturated” vs. Chimps who “can be enculturated”


   • Easy to find experimental subjects


• Everybody likes a good dog story
     Hare, B. and M. Tomasello (2005). "Human-like Social Skills in Dogs." Trends in Cognitive Science 9(9): 439-447.



        Using dogs as a model to
understand the evolution of social                                             Why the the funding agencies
                                                                               care
             cognition in humans
Why I/we care...

• What can we learn that will help us understand


   • why the dogs in our households do what they do


   • how to better raise behavorally-healthy dogs


   • how to better train and interact with our dogs


   • how to better ensure that our dogs stay behaviorally healthy.
The big picture

• Do pet dogs use human cues (gestures, gaze, body position, motion, voice) to
  guide their behavior?


  • Well, do they?


  • If so, to what feature are they attending?


  • Why are they using the feature?


  • What mental representation do they build, i.e., is it a ‘simple’ association or
    do they understand the meaning of the cue at some ‘deeper’ level.


  • What larger story does this tell?
In fact there are 4 big
questions to ask...

• Function: how does it enhance
  survival


• Causation: what elicits the
  behavior, and are there learned
  components?


• Development: when does the
  behavior appear and what role
  does development &
  developmental context play?


• Evolution: do you see it in       Niko Tinbergen
  related species how might it
  have arisen via evolution?
Hare, B. and M. Tomasello (2005). "Human-like social skills
in dogs?" Trends in Cognitive Science 9(9): 339-444

                                                              Miklosi, A. and K. Soproni (2006). "A comparative
                                                              understanding of the human pointing gesture."
                                                              Animal Cognition 9: 81-93.




                        Pointing gestures as                           Experiments do try to control for
                                                                       olfactory cues
                                        cues
 Call, J., J. Brauer, et al. (2003). "Domestic Dogs (Canis Familiaris) Are
 Sensitive to the Attentional State of Humans." Journal of Comparative
 Psychology 117(3): 257-263.




Attentional state as                                        Is the dog more likely to grab the
                                                            treat if the person isn’t facing
               cues                                         them?
                                     Viranyi, Z., J. Topal, et al. (2004).
                                     "Dogs respond appropriately to cues of
                                     humans' attentional focus." Behavioural
                                     Processes 66(2): 161.




                            Is the dog sensitive to the
Attentional state as cues   apparent attention of the person?
                  What is the mechanism behind
Words as labels   word use?
                                  Miklosi, A., P. Pongracz, et al. (2005). "A
                                  Comparative Study of the Use of Visual
                                  Communicative Signals in Interactions Between
                                  Dogs (Canis Familiaris) and Humans and Cats
                                  (Felis catus) and Humans." Journal of Comparative
                                  Psychology 119(2): 179-186.




  Experiments generally show
                                 These results are more or less
that dog’s choice is biased by   typical
                gestural cues
Things to note about experiments

• Small number of subjects with repeated trials


• Criteria is statistically different than chance


• Results are typically aggregated


• Typically subjects are adult pet dogs recruited from local training clubs, friends,
  etc.


• Class 11 we will revisit methodology because it is often problematic
Hare 2002 - 2005
                                                                    9 out of 11 dogs
                                                                    used cue vs. 2
                                                                    out of 11 for
                                                                    chimps




Hare, B., M. Brown, et al. (2002). "The domestication of social
cognition in dogs." Science 298: 1634-1636.




                                                    The difference between dogs &
               Hare 2002                            chimps was startling, and the
                                                    question was why?
Hare’s Three Hypotheses (2002)

• “Canids in general are unusually flexible in the types of social information they
  can exploit”


• “Domestic dogs ... have learned their skills during their individual ontogenies”


• “Selection pressure on dogs during process of domestication for specific skills
  of social cognition and communication with humans”
                                                                            No wolf performed above
                                                                            chance using any cue. 7
                                                                            dogs used GPT, 5 used GP,
                                                                            4 used P to find food above
                                                                            chance. 3 dogs used all 3
                                                                            cues, 3 dogs used 2, and 1
                                                                            dog used just one.




                   Gaze,          Gaze,         Point           Control
                   point,         point
                   touch


          Hare, B., M. Brown, et al. (2002). "The domestication of social
          cognition in dogs." Science 298: 1634-1636.




Dogs performed differently                                 This suggested to Hare that it
                                                           wasn’t an ability common to
  than ‘socialized’ wolves                                 canids
                                                                            Differences aren’t
                                                                            significant, but interesting
                                                                            that litter-reared did
                                                                            better than family raised.




          Hare, B., M. Brown, et al. (2002). "The domestication of social
          cognition in dogs." Science 298: 1634-1636.




Litter raised pups did the
                                                          This suggested to Hare that it
    same as family raised                                 wasn’t developmental
                     pups
9-12 week pups did as
                        This suggested to Hare that there
   well as 17-24 week   wasn’t a learned component
                 pups
Hare’s big conclusion

• “These findings suggest that during the process of domestication, dogs have
  been selected for a set of social-cognitive abilities that enable them to
  communicate with humans in unique ways.”
Things to think about...

• Are there flaws with the experimental design and analysis?


• There is an assumption that socialized wolves are the same as socialized dogs.
  Is this valid?


• There is an assumption that extensive contact with humans prior to 8-12 weeks
  is required for pups to preferentially attend to humans. Is this valid?


• There is an assumption that social learning doesn’t occur prior to 8-12 weeks. Is
  this valid?


• There is an assumption that you can describe a generic pet dog, and that one
  can generalize across breeds. Is this valid?
Hare 2005

• Hare’s statement: “dogs have an unusual ability for reading human
  communicative gestures... seems to have evolved during domestication”


• Hare’s question: “unclear whether this evolution occurred as a result of direct
  selection for this ability... or as a correlated by-product of selection against fear
  and aggression toward humans”


• Decided to test hypothesis using domesticated foxes that were explicitly bred to
  have reduced fear and aggression toward humans




             Hare, B., I. Plyusnina, et al. (2005). "Social Cognitive Evolution in Captive Foxes Is a
             Correlated By-Product of Experimental Domestication." Current Biology 15: 226-230.
Trut, L. (1999). Early Canid Domestication: The Farm Fox Experiment. American Scientist. 87: 160-169




                                                                       we will keep coming back to Dr.
                 Belyaev’s foxes...                                    Belyaev & his foxes
Belyaev’s Fox experiment...

• Initial goal was to produce tamer foxes


• Started with a population of 465 foxes


   • 30% extremely aggressive (threatening?)


   • 40% moderately aggressive (threatening?)


   • 20% fearful


   • 10% quiet & exploratory
Belyaev’s Fox
experiment...

• Criteria for breeding


   • Flee threshold


   • Flee distance


   • later generations, willing to
     approach


• After 18 generations they had
  produced foxes that had some
  ‘dog-like’ behavioral and
  morphological characteristics...
      Trut, L. (1999). Early Canid Domestication: The Farm Fox Experiment. American Scientist. 87: 160-169




Significant change in timing of                                              We definitely will be coming back
                                                                             to this one
    developmental milestones
Pups & fox kits
between 8-16
   weeks




                  Hare, B., I. Plyusnina, et al. (2005). "Social Cognitive Evolution in Captive Foxes Is a
                  Correlated By-Product of Experimental Domestication." Current Biology 15: 226-230.




   Pups & domesticated fox kits                                                     This suggested to Hare that this
                                                                                    skill was a by product of selection
            performed similarly                                                     for tameness
           Hare, B., I. Plyusnina, et al. (2005). "Social Cognitive Evolution in
           Captive Foxes Is a Correlated By-Product of Experimental
           Domestication." Current Biology 15: 226-230.




Temperament of farm foxes                                     This experiment was consistent
                                                              with Hare’s view that this skill
       may interfere with                                     was a side-effect of breeding for
            performance                                       temperament
Hare’s conclusions...

• 2 alternative explanations for dog’s ability to read human signals


   • Communication hypothesis: this ability was directly selected for during
     domestication


   • Correlated by product hypothesis: this ability is simply a by-product of
     selection for tameness


• He believes his results support correlated by-product hypothesis...


   • Nothing was being selected for other than tameness (e.g., ability to read
     human cues) and yet foxes did as well as pet dog pups
Things to think about...

• At one level, all Hare is saying is that cognition takes place in an emotional
  context. This highlights the central role that emotions and temperament play in
  a dog’s choice of what to attend to, and what to do.


   • This is why we devote so much time to emotion and temperament


• What are the specific mechanisms that make a pet dog emotionally prepared to
  interact & attend to humans?


   • Can we tease apart the complex interplay of genes, development,
     developmental context, & learning?


   • This is why we devote so much time to development
Is this the whole story?
• Hare’s argument: lowered emotional reactivity was selected for, and at a
  minimum, this set the stage.


   • How much more is needed?


• Miklosi’s argument: that is not the whole story, social skills were selected for as
  well...
Kubinyi et al, 2007
Social evolution: from wolf and dogs to humans

• Research question: can we use the presumed evolution of social cognition in
  dogs to say anything about the evolution of social cognition in humans?


• They claim dogs are an interesting model because...


  • “Behavior changed in a way that made them successful in the human social
    environment”


  • “Behavior of dogs’ ancestor species can be reconstructed from the behavior
    of the wolf”


  • “The natural socialization of dogs in the human environment offers a parallel
    between them and children.

              Kubinyi, E., Z. Viranyi, et al. (2007). "Comparative Social Cognition: From wolf and dog
              to humans." Comparative Cognition & Behavior Reviews 2: 26-46.
Unique evolutionary history...

• Dogs were first domesticated animals (when this occurred will be a topic for
  another lecture...)


• Their model


   • subset of wolves adapted to new ecological niche provided by humans


   • traits implicitly/explicitly selected for by humans


   • Explicit selection for behavioral and morphological traits (19th century)
     produced dog breeds.
The family wolf project: if wolves are raised like pet
dogs, do they act like pet dogs?

• They take as a given that dogs and wolves have a very different developmental
  time course...


  • Critical period for socialization seems to begin prior to 10 days in wolves vs.
    3 to 5 weeks in dogs, and in dogs it extends up to 12 weeks.


  • In wolves, 24/7 contact with humans seems to be required


  • In pet dogs, minimal contact/presence seems to be enough to scaffold
    social attraction to another species (such as humans...)


  • Presence/absence of litter-mates seems to have a different effect in wolves
    vs. dogs.


  • Why this should be is the most fascinating question of all to me!!!!!!!!
The family wolf
project

• Its a tough job but somebody
  has to do it :-)


• 13 wolf cubs & 11 pups


• Raised similarly


• Tracked comparative behavior
  over approximately 2 years


• “... intensive early handling
  proved to be an effective means
  of socializing wolves to a level
  comparable to dogs...”
                                     Kubinyi, E., Z. Viranyi, et al. (2007). "Comparative Social
                                     Cognition: From wolf and dog to humans." Comparative
                                     Cognition & Behavior Reviews 2: 26-46.
                                           Kubinyi, E., Z. Viranyi, et al.
                                           (2007). "Comparative Social
                                           Cognition: From wolf and dog to
                                           humans." Comparative Cognition
                                           & Behavior Reviews 2: 26-46.




       Statistically different
                                  Must depend on more than social
performance on attachment         experience...
                        test...
Pet dogs seem to be able to
use pointing gestures more
easily...

• “dog puppies as young as 4
  months old are able to perform
  well... without any special,
  intensive, and early socialization
  to humans”


• Significant difference in
  performance between 4 month
  old wolf cubs and pet dog pups,
  but...


• “After extensive training, wolves
  significantly improved in parallel
  with increased readiness to look
  at the pointing human.”              Kubinyi, E., Z. Viranyi, et al. (2007). "Comparative Social
                                       Cognition: From wolf and dog to humans." Comparative
                                       Cognition & Behavior Reviews 2: 26-46.
Wolves may be less
likely to look at
people

• Tested wolves are significantly less
  likely to look to their handler when
  working on a blocked task, and
  when they do look, spend less time
  looking.


• Attention is a prerequisite for
  learning. If wolves are biased
  against, or dogs biased toward
  attending to humans one would
  expect a difference in...


   • Learning to use human
     generated cues


   • Use of those cues to guide
                                         Kubinyi, E., Z. Viranyi, et al. (2007). "Comparative Social
     behavior                            Cognition: From wolf and dog to humans." Comparative
                                         Cognition & Behavior Reviews 2: 26-46.
Miklosi’s interpretation

• Wolves aren’t as good at using human cues as dogs because of “their
  decreased willingness to look at the human”


• Conversely, “preferential looking at the human seems to be a genetic
  predisposition of dogs”...


   • at this is the “foundation on which developmentally canalized complex
     communicative interactions can emerge between man and dog”


• In other words, a genetic bias to look at people was a precursor to the
  coevolution of dog-human communicative skills.



              Miklosi, A., E. Kubinyi, et al. (2003). "A Simple Reason for a Big Difference: Wolves Do
              Not Look Back at Humans, but Dogs Do." Current Biology 13(9): 763.
Miklosi et al call this apparent difference in
attention: “A simple reason for a big difference”

• They suggest 2 processes might have been at work...


   • A bias to attend to people, and all that that brought along with it, may have
     been implicitly or explicitly selected for


      • Natural or artificial selection


   • Lower emotional reactivity in dogs may allow dogs to “tolerate being gazed
     at by humans better than wolves”


• In either case: a genetic bias to look at people may have been a precursor to
  the co-evolution of dog-human communicative skills.
Some things to keep in mind...

• Any bias that exists in dogs...


   • may be to members of an imprinted species rather than limited to humans
     (e.g., live stock guarding dogs raised with sheep).


   • may have a wide variance across individual dogs and across breeds, e.g. a
     border terrier trying to get a rat in a cage doesn’t spend a lot of time looking
     back at its handler either...


   • it may well have arisen as a side-effect of some other difference...


      • There doesn’t need to be, and mostly likely isn’t, a gaze-at-human gene.


      • May not have been directly selected for.
Social learning: from simple cues to selective
imitation
                       Local enhancement: “I think I’ll hang
                       out with Harry. Hmmm, what’s that”




                       Stimulus enhancement: “Hey what’s
                       Harry fooling with. That looks tasty”




                       Observational Conditioning: “Yikes,
                       what is Harry reacting to, I guess I
                       should be scared too”




Three simple types of social        Just because its simple, doesn’t
                                    make it any less useful
                   learning
These previous types of social learning can be
explained via associative learning, but...

• Josep Call postulates 2 alternative mechanisms...


   • The ‘cue-based’ approach. The animal learns to respond to a given stimulus
     in a given way, or learns to predict a given future stimulus based on
     observing another given stimulus.


      • All about correlation, no mental model of causation, and hence little or no
        ability to generalize.


   • The ‘knowledge-based’ approach. Here the animal extracts functional
     features associated with the stimulus, and builds a functional model of
     greater or lessor complexity that it then uses to guide its choice of behavior


      • To the extent that the functional model accurately captures causation, it
        provides a mechanism to generalize.
          Call, J. (2001). "Chimpanzee social cognition." Trends in Cognitive Science 5(9): 388-393.
Selective imitation

• Dogs trained to pull a ring for food via
  mouth and paw


• Control dogs given opportunity to
  solve this problem on their own. 85%
  used their mouth to pull on the rod.


• Experimental dogs watched 8 trials of
  a demonstrator using their paw to
  push down on the rod.


   • One group, demonstrator has ball
     in mouth


   • Other group, demonstrator doesn’t
     have a ball in mouth
                                             Range, F., Z. Viranyi, et al. (2007). "Selective Imitation in
                                             Domestic Dogs." Current Biology 17: 1-5.
          Clear difference in
performance between the two     But why???
                      groups
Possible explanations...

• The dogs really are making the kinds of inferences that I have described on the
  previous pages...


   • If so, this is both quite remarkable and quite unexpected


• Is there some confounding factor that isn’t apparent to us that makes it appear
  as if the dog is making an inference when in fact they are responding to
  something else in the experimental set-up.


• In either case, it is a fascinating question to ponder...
In the end...

• The course will focus on many of the issues that are at the heart of much of the
  work described above.


   • origins of the dog


   • development


   • emotion & temperament


   • social learning


• In class 11 and class 15 we will re-examine the original work with maybe a few
  more answers to the questions, and even more questions
Next week: wolves & wild canids

								
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