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it is well articulated presentation on visual signal communication. I would like if I have permission from the author to download this particular presentation

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Linguistics 001, Fall 2004 : 

Linguistics 001, Fall 2004 Animal Communication

Basics: 

Basics Following our examination of human language; a look at communication in other species Two components: Language vs. Communication What to look at: What animals do, in their normal environment Attempts to teach human language to non-human species Today: Examine (and review) differences between human language and other systems, and then look at examples of what animals actually do

Properties of language and animal communication: 

Properties of language and animal communication Many of the differences between systems of animal communication and language are centered on properties of language that we have encountered before ]While there may be some points in common between what happens in human language and what happens in (natural) animal communication, there are many differences as well

Signal Set: 

Signal Set Animal communication systems have a limited signal set: the inventory of things that are communicated about is very limited (e.g. food, sex, aggression, predators/threats) Human language, recall, has the ability to incorporate new basic elements (typically words) in a way that is unlike what is found in animals Moreover there is nothing like syntax for generating new ‘utterances’ in the animal kingdom (in some domains linear order is important, however, e.g. birdsong)

Reference: 

Reference Consider a simple example of communication: dog posture. In this case, the dog is communicating that it is ready to play (the following is a game)

Reference, II: 

Reference, II The dog in the example above is communicating something, namely, something about its internal state With reference, we mean roughly what it is that a signal in communication refers to Most animal communication systems are limited in what their signals are capable of referring to; typically, an internal state, or an immediately present stimulus

Displacement: 

Displacement What the reading refers to as situational freedom or displacement involves referring to things that are not immediately present This is an obvious property of human language; but with limited exceptions, this is clearly not the norm in animal communication

Some examples: 

Some examples Two different communication systems; bees and vervet monkeys Vervet Monkeys: different calls for different predators, which trigger appropriate behavior Bees: Communicate distance and location (relative to the hive) of food sources

Vervet Monkeys: 

Vervet Monkeys (multimedia from Hauser’s webpage, http://www.wjh.harvard.edu/~mnkylab/media/vervetcalls.html) Snake Alarm: Hearers stand on hind legs and look on the ground Leopard Alarm: Hearers run to the top of the nearest tree (where leopards can’t go) Eagle Alarm: Vervets run under a bush/cover of tree branches

Function: 

Function The organization of the alarm system makes sense given the living conditions of the vervets The predators are categorized in different ways: in particular, ways that require different responses Categorization is acquired in the first four years of life; young vervets miscategorize, but eventually learn the correct association of calls with predators (without, apparently, any correction)

Comments: 

Comments Note that there are several ways in which to interpret what the different calls might ‘mean’, if we approach it that way ‘Leopard!’ ‘Head for the trees!’ Etc. Even in systems of this type, which show some complexity because of the categorizations involved, we still seem to have calls made in the presence of some stimulus

Bee Dancing: 

Bee Dancing Honeybees forage for food sources and, upon returning from a successful trip (i.e. after finding a food source) they perform a dance This dance is called the waggle dance because it involves this particular motion The waggle dance conveys aspects of the journey the bee has completed– in particular, the location and distance of the food source Other bees that have witnessed the dance then go to the food source (or a lot do, in any case)

The dance: 

The dance The dance proceeds in a figure 8 pattern The orientation of the dance with respect to either vertical or the position of a light indicates the direction (other factors indicate approximate distance)

Orientation: 

Orientation Dances oriented directly to vertical indicate that food is in line with the sun Otherwise, the orientation of the dance indicates the angle of the food from the sun

Competing Hypotheses: 

Competing Hypotheses One possibility with the bee dance is that it does not actually encode information I.e. other factors, such as scent (which bees also use) were thought to be responsible for the fact that bees could find sources after a dance An experiment designed to test this hypothesis versus the communication one involves making a bee ‘lie’ to others

Further facts: 

Further facts The experiment involves a further fact about the bee dance When it is dark in the hive, the dance is oriented towards vertical When there is a light source visible in the hive, the dance is oriented towards the light source This provides the basis for a way to test what the bees witnessing a dance are actually doing

Making bees lie: 

Making bees lie Bees detect overall light with their ocelli, a set of photoreceptors on top of the head Experiments can paint the ocelli of bees, so that bees with painted ocelli behave as if it is dark, whereas bees with unpainted ocelli act as if it is light The experiment involves bees with painted ocelli dancing about the location of a food source; the dance is witnessed by bees with unpainted ocelli

The idea: 

The idea Dancing Bees: The dancing bees orient with respect to vertical Witnessing Bees: The witnessing bees interpret the dance with respect to a light source, which is not at vertical Result: Witnessing bees (the majority) went to the source that was indicated by the dance, not the source actually visited by the dancing bees (who were giving false information) This is consistent with the communication hypothesis, but not the odor-alone hypothesis.

Human language in non-humans: 

Human language in non-humans Another aspect of research on language in animals involves a different methodology than studying communications systems that are natural to non-human species This involves trying to teach non-human animals (typically chimpanzees, bonobos, or e.g. gorillas in the case of Koko) human language

On the methodology: 

On the methodology To some extent, studies of this type capture the popular imagination, often concentrating on the question of whether animals have ‘true language’ The bulkpack reading quotes a paper by Snowdon (1993) with a perspective on this: “…ethologists who study natural communication differ from psychologists who try to teach human language to other species in the same way as anthropologists differ from missionaries. Anthropologists try to understand the natives whereas missionaries try to civilize them.”

Some facets of the program: 

Some facets of the program In most of these cases, the primates were taught some version of sign language, such as with Washoe In a few cases, the primates were taught visual symbols There are some differences as well in the training situation (home, laboratory, etc.)

Basic Results: 

Basic Results In the basic case, it seems clear that the primates are able to associate signs (whether visual or manual) with a ‘meaning’ This is unsurprising given that many species can associate a symbol of some type with something else (consider e.g. dogs) Whether this amounts to the primates having a ‘vocabulary’ is a more difficult question

Harder questions: 

Harder questions An additional question is whether the primates who have been studies are able to use new symbols in new combinations This is, of course, a central facet of human language In many cases, claims for new use of symbols or ‘proto syntax’ are taken from long sessions, and are not always representative For instance, it has been claimed that Lana, upon encountering an orange for the first time, signed: “apple which-is orange-color”

More context: 

More context Tim: What color of this ? Lana: Color of this orange Tim: Yes Lana: Tim give cup which-is red Tim: Yes Lana: Tim give which-is shut ? Shelley give ? Tim: No Shelley Lana: Eye // Tim give which-is orange? Tim: What which-is orange Lana: Tim give apple which-is green ? Tim: No apple which-is green Lana: Tim give apple which-is orange ? Tim: Yes Lana Note the use of fixed expressions and the fact that the trainer introduced color into the conversation

Synopsis: 

Synopsis The idea that human language should be taught to non-humans involves several components One the one hand, it is asking primates to do something that they do not by nature do This seems to relate to a perspective on human language which we have found evidence against before: if language is just general intelligence, then primates and other ‘intelligent’ species should be able to learn some of it Of course, we might learn something about primate intelligence in such projects, but what we learn about human language is limited

Conclusions: 

Conclusions In complex systems of animal communication, there are questions about What animal calls, etc. ‘refer to’ (if they refer) Whether or not they are used to influence the behavior of others, or are simply responses to stimuli Some evidence exists for the encoding of information about stimuli that are not present (bees) It is unclear what can be learned about language per se from experiments that try to teach human language to non-humans