Neuroethologists have commonly followed a “model-systems” approach
to behavior by focusing on species-specific behavior patterns typical of particular groups of animals. This has yielded cohesive “stories” about prominent examples, such as advertisement calling in frogs, singing in birds, and
echolocation in bats. The advantage of the model- systems approach derives
from the fact that, for any particular species, the acoustic stimuli that have
to be considered are well-defined and do not range widely over all possible sounds. An integrated approach to behavior need not be limited to
highly specialized systems, however. The neuroethological perspective
allows insights into both more general and more species-specific physiological mechanisms and evolutionary adaptations. For example, both songbirds and humans can selectively discriminate and attend to specific sounds
of interest within a complex acoustic scene, and they may use similar
acoustic cues to achieve this segregation (Hulse et al. 1997). Neural mechanisms of sound segregation obviously are much more amenable to study
in birds than in humans, even with the advent of noninvasive imaging techniques. Results from neuroethological studies have ranged far beyond
descriptions of unusual or bizarre behaviors in strange organisms with no
relevance to understanding “less specialized” animals. Crucially, some widespread principles of neural organization (combination-sensitive neurons,
distorted tonotopic maps, parallel cortical representations) were first quantified in the brains of highly specialized model systems and then later
observed to operate in the nervous systems of other animals (Suga 1988;
Gentner and Margoliash, Chapter 7). Then, too, in an evolutionary sense,
all communication systems are specialized in that each has evolved in relation to specific ecological niches and selection pressures to emphasize particular types of signals and variability in their parameters.
2. What Is Communication?
Acoustic communication, using speech, is something humans do every day.
Acoustic communication using both simple and complex sounds is also very
common among vertebrate and invertebrate animals. Operational definitions of what we mean by communication are many (see, for example Green
and Marler 1979; Hauser 1997; Bradbury and Vehrencamp 1998). Each set
of authors in this volume provides a short definition of acoustic communication as it has guided their choice of material.
Most broadly, we can define communication as the transfer of information (a message) between a sender and a receiver. Although communication is often thought of as an intragroup interaction among members of the
same species, it need not be restricted in this way. Acoustic signals used for
communication can have widely varying information content and thus
convey either very explicit or very vague messages. For example, signals
might convey a broad message, such as species identity between groups, or
4
A.M. Simmons
to behavior by focusing on species-specific behavior patterns typical of particular groups of animals. This has yielded cohesive “stories” about prominent examples, such as advertisement calling in frogs, singing in birds, and
echolocation in bats. The advantage of the model- systems approach derives
from the fact that, for any particular species, the acoustic stimuli that have
to be considered are well-defined and do not range widely over all possible sounds. An integrated approach to behavior need not be limited to
highly specialized systems, however. The neuroethological perspective
allows insights into both more general and more species-specific physiological mechanisms and evolutionary adaptations. For example, both songbirds and humans can selectively discriminate and attend to specific sounds
of interest within a complex acoustic scene, and they may use similar
acoustic cues to achieve this segregation (Hulse et al. 1997). Neural mechanisms of sound segregation obviously are much more amenable to study
in birds than in humans, even with the advent of noninvasive imaging techniques. Results from neuroethological studies have ranged far beyond
descriptions of unusual or bizarre behaviors in strange organisms with no
relevance to understanding “less specialized” animals. Crucially, some widespread principles of neural organization (combination-sensitive neurons,
distorted tonotopic maps, parallel cortical representations) were first quantified in the brains of highly specialized model systems and then later
observed to operate in the nervous systems of other animals (Suga 1988;
Gentner and Margoliash, Chapter 7). Then, too, in an evolutionary sense,
all communication systems are specialized in that each has evolved in relation to specific ecological niches and selection pressures to emphasize particular types of signals and variability in their parameters.
2. What Is Communication?
Acoustic communication, using speech, is something humans do every day.
Acoustic communication using both simple and complex sounds is also very
common among vertebrate and invertebrate animals. Operational definitions of what we mean by communication are many (see, for example Green
and Marler 1979; Hauser 1997; Bradbury and Vehrencamp 1998). Each set
of authors in this volume provides a short definition of acoustic communication as it has guided their choice of material.
Most broadly, we can define communication as the transfer of information (a message) between a sender and a receiver. Although communication is often thought of as an intragroup interaction among members of the
same species, it need not be restricted in this way. Acoustic signals used for
communication can have widely varying information content and thus
convey either very explicit or very vague messages. For example, signals
might convey a broad message, such as species identity between groups, or
4
A.M. Simmons