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D.L. Herzing
might favor a combination of mechanisms, that is, a highly horizontal
culture would favor rapid adaptations with some stabilizing reality checks
of vertical learning such as time-honored, tested, and proven traditions.
Social learning would permit rapid evolution (e.g., faster than genetic
changes for mate selection). Oblique transmission is also conducive to utilizing the repository of experience and information available from older,
more experienced individuals in the society.
As we increase our abilities to gain finer detailed information about age
class, gender, individuals, and relationships in a society, we increase our
ability to understand what information is available. Developmental aspects
of categorizing sounds have been documented for primates (Seyfarth and
Cheney 1980) and other terrestrial species. It is likely that such insight into
delphinid societies will yield similarly valuable information. Comprehension of cultural information is thought to be primary to production (SavageRumbaugh et at. 1986). Developmental emphasis on exposure to listening
and feedback of appropriate behavior may be important in a society, that
is, production may occur only when an individual is required by circumstance to lead or communicate an action or intention.
An extended maturational period of development, the period of both
physical and social weaning before sexual maturity, may serve as a time to
refine the decoding of social signals. The focus of juvenile activity beyond
the basic survival issues of foraging, includes play, a high-risk activity yet
one that is acceptable in adult circles and carries a meta-message of signal
use. Societies with cross-generational or even cross-species access to transfer of information are well suited for learning. In many species of openocean delphinids, age classes overlap on a regular basis and in some, mixed
species aggregations are common. In the Bahamas, a complex relationship
between T. truncatus and S. frontalis extends the exposure to cross-species
communication signals. Mimicry, both vocal (Richards et at. 1984) and postural (Xitco 1988; Herzing 1996) has been documented and is a likely mechanism for transmission and learning. Dolphins are reported to hear human
vocalizations above water and adapt and extend their own species signals
to humans (Pryor 1986). Complex informational exchange between species,
including aggression and cooperation, is likely with sympatric species exposure at a young age (Herzing and Johnson 1997).
How might dolphin hearing be intertwined with such transmission mechanisms? Young dolphins must be able to detect, decode, and decipher
signals from the environment in order to react appropriately, both physically and socially. In social contexts it may be difficult for us to observe
signal use and its associated circumstances and behavior. Messages (vocal,
visual, and tactile) can be nonbehavioral, such as age, location in space, and
identification, or behavioral, which allows prediction of social outcomes or
impending behavior (proximal or long-distance). Messages can also be
broad, signaling a general state of arousal by posture or types of signals, or
subtle, where encoded information is specific to an individual's state by such
D.L. Herzing
might favor a combination of mechanisms, that is, a highly horizontal
culture would favor rapid adaptations with some stabilizing reality checks
of vertical learning such as time-honored, tested, and proven traditions.
Social learning would permit rapid evolution (e.g., faster than genetic
changes for mate selection). Oblique transmission is also conducive to utilizing the repository of experience and information available from older,
more experienced individuals in the society.
As we increase our abilities to gain finer detailed information about age
class, gender, individuals, and relationships in a society, we increase our
ability to understand what information is available. Developmental aspects
of categorizing sounds have been documented for primates (Seyfarth and
Cheney 1980) and other terrestrial species. It is likely that such insight into
delphinid societies will yield similarly valuable information. Comprehension of cultural information is thought to be primary to production (SavageRumbaugh et at. 1986). Developmental emphasis on exposure to listening
and feedback of appropriate behavior may be important in a society, that
is, production may occur only when an individual is required by circumstance to lead or communicate an action or intention.
An extended maturational period of development, the period of both
physical and social weaning before sexual maturity, may serve as a time to
refine the decoding of social signals. The focus of juvenile activity beyond
the basic survival issues of foraging, includes play, a high-risk activity yet
one that is acceptable in adult circles and carries a meta-message of signal
use. Societies with cross-generational or even cross-species access to transfer of information are well suited for learning. In many species of openocean delphinids, age classes overlap on a regular basis and in some, mixed
species aggregations are common. In the Bahamas, a complex relationship
between T. truncatus and S. frontalis extends the exposure to cross-species
communication signals. Mimicry, both vocal (Richards et at. 1984) and postural (Xitco 1988; Herzing 1996) has been documented and is a likely mechanism for transmission and learning. Dolphins are reported to hear human
vocalizations above water and adapt and extend their own species signals
to humans (Pryor 1986). Complex informational exchange between species,
including aggression and cooperation, is likely with sympatric species exposure at a young age (Herzing and Johnson 1997).
How might dolphin hearing be intertwined with such transmission mechanisms? Young dolphins must be able to detect, decode, and decipher
signals from the environment in order to react appropriately, both physically and socially. In social contexts it may be difficult for us to observe
signal use and its associated circumstances and behavior. Messages (vocal,
visual, and tactile) can be nonbehavioral, such as age, location in space, and
identification, or behavioral, which allows prediction of social outcomes or
impending behavior (proximal or long-distance). Messages can also be
broad, signaling a general state of arousal by posture or types of signals, or
subtle, where encoded information is specific to an individual's state by such