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- INTRODUCTION
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- Social communication among primates is a
biological phenomenon and, like any other
biological process, presents us with several
major questions: (1) What is its structure? (2)
How does it function? (3) What is its underlying
causation? (4) How does it develop
ontogenetically? (5) What is its adaptive
significance? (6) How did it evolve? As with
other biological processes descriptions of what
we may call the "anatomy" or "structure" of
communication are bound to be a primary focus of
research attention during this early stage in
work on primate behavior. Indeed, our ability
adequately to answer the remaining questions
will depend upon an understanding of the
structure of communication. The special nature
of such a structure lies in this: it is a
structure not of objects but of events.
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- Addressed (Directed) Messages
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- Closely related to the distinctions between
broadcast vs. narrow-band transmission and
directional vs. nondirectional reception is the
fact that some messages are directed toward
particular individuals or groups, whereas others
are to-whom-it-may-concern messages. Undirected,
to-whom-it-may-concern messages do occur among
primates, particularly in their predator-alarm
calls and in their group-cohesion calls, both of
which have been reported in many primates.
However, most of the social signals of primates
seem to consist of directed displays.
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- Messages may be directed in several ways.
One way is to restrict the channel of
transmission (for example, by using a quiet
vocalization or a tactile message), so that the
message is received only by certain individuals.
Another is to use a private code or language
known to some but not all of the recipients. A
third way is to add to the message an ancillary
component that indicates to whom the message is
being directed.
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- Those components of a message that serve to
direct it may be referred to as the address of
the message. Note that addresses are,
themselves, messages. They are communication
about communication, that is, metacommunication
(Bateson 1955). (Eavesdropping is the example
par excellence of responding to messages that
are directed toward someone else.) Itani (1963),
in discussing Japanese macaque vocalizations
that form his Group A, most of which are used in
the coordination of group movements, writes,
"few of them are directed at an individual. Some
sounds are so low that they do not reach except
a short distance, and others are loud and big
enough to reach the whole troop. It is clear,
however, judging from the manner and the line of
gaze of the utterers, that generally they are
not calling to a special individual."
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- Among primates-and doubtless among many
other animals-facing and looking at the
addressee is probably the most common means by
which social messages are directed. (Doubtless,
the efficiency of this technique is to some
extent dependent upon the fact that for an
animal with extensive binocular vision the
position of the two eyes on the front of the
face makes it fairly clear to other members of
the group just who is being looked at.) Even
when females present their hindquarters to a
male, an act which in itself has conspicuous
cues about who is the addressee, there is often
visual contact or, at least, facing (Plate
17.2). Thus, one interpretation of avoiding
visual contact-which has been described in
rhesus (Altmann 1962a, Hinde and Roweil 1962),
baboons (Hall 1962, DeVore 1962), bonnet
macaques (Simonds 1965), gorillas (Schaller
1963)-is that it is a means of avoiding
interactions. Not surprisingly, this behavior is
usually given by the subordinate member of a
pair, and its converse, direct staring, is
usually a form of threat. Note that in such
situations organs that are fundamentally
receptors have come to subserve a transmitting
function; according to Bateson and Jackson
(1964), this is a common development in animal
communication.
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- Particularly striking is the fact that
messages may be directed toward the appropriate
sense organ of the social partner. In our
studies of baboons, this was not observed in
vocal signals-which is not surprising, in view
of crookedline transmission of sound waves
(property 7). It was, however, conspicuous in
many visual and olfactory displays (Plate 17.2).
Adolescent males, at an age when they first
began to make use of the mouth-gape or
"yawn" as a threat were very poor at
directing these displays (Plate 17.3).
Gradually, however, they became more skilled at
directing these displays toward the face, and
hence eyes, of the females whom they harassed.
This gradual perfecting of the technique of
directing these displays may have developed out
of repeated experience with the relative
communicative impact of displays that varied in
the extent to which they were directed toward
the relevant sense organs.
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- This last case points up the fact that the
directing components of a message may follow a
different maturational pattern than the displays
themselves. Jay (1962), describing the Indian
langur, Presbytis entellus, writes, "in the late
infant-1 stage the young langur produces the
earliest recognizable forms of gestures and
vocalizations which will be characteristic of
its adult behavior.
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- Improved coordination makes it possible to
direct movements towards objects and other
monkeys . . . ."
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- In sothe cases, the presence or absence of
addressing components may determine whether a
particular display is communicative. Jay (1962)
indicates that undirected grimaces, which are
given by young langurs in play, are of no
communicative significance, whereas directed
grimaces outside of the play situation are. In
baboons, directed mouth-gaping, or
"yawning," is a powerful threat; in
contrast, undirected yawns are of little
or no communicative significance.
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- The directing or addressing component of a
message may have a "pointing" function. When a
monkey in an agonistic situation attempts to
enlist aggression from a third party, and
particularly when such a third party draws near
(for example, when a female comes to the aid of
one of her offspring), the monkey often gives
agonistic displays toward the opponent with
exaggerated addressing components, thereby
singling out the adversary; we have observed
this in rhesus macaques and savannah baboons.
Itani (1963) indicates that Macaca fuscata may
communicate the location of a concealed invader
to the troop through "triangulation" of the
directing components; an alarm call and various
threat gestures are given repeatedly by a monkey
from 5 to 15 m from the invader, and as the
monkey continues his call incessantly, using
trees and rocks as a shield, he jumps about,
covering a half circle in which the invader is
the center.
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- The concept of directed messages enables one
to translate into verifiable form many
statements about intent. For example, "The male
intended to strike the female" might be reworded
"The male directed his strike at the female (but
missed)." In some cases, this may clarify the
empirical basis for the impression that we know
the subjective state of the organism.
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- A peculiar form of directed behavior has
been observed in rhesus, bonnet, and Japanese
macaques (Altmann 1962a, Simonds 1965, Itani
1963) and probably occurs in other primates as
well. A behavior may be directed at nobody. This
is not the same as undirected behavior. For
example, a rhesus female sometimes will, while
presenting to a male, direct a threat toward
some fixed position that is not occupied by
anybody. This seems to be a particularly strong
stimulus to mounting. The behavior of a female
in these situations appears to be
indistinguishable from that in which she
presents to a male while threatening an actual
third party. Itani (1963) writes of the Japanese
macaque:
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- An individual is attacked by a superior
individual. He tries to direct the attack by
uttering these sounds to a third individual
nearby who has no connection with the trouble.
When he finds no available third person about
there, he utters these sounds toward an entirely
false direction, that is, to an imaginary
object, so that he can sometimes escape from his
situation of being attacked.
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