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130 Chapter 9

for its affiliated behavior to become active. Because each releaser is not overly specific
or precise, it is possible to “fool” the animal by devising a mock stimulus that has the
right combination of features to elicit the behavioral response. In general, releasers are
conceptualized to be simple, fast, and just adequate. When engaged in a particular behavior,
the animal tends to only attend to those features that characterize its releaser.
Motivational Contributions
Ethologists have long recognized that an animal’s internal factors contribute to behavioral
relevance. I discussed two examples of motivating factors in chapter 8, namely homeostatic
regulatory mechanisms and emotions. Both serve regulatory functions for the animal to
maintain its state of well-being. The homeostatic mechanisms often work on slower time-
scales and bring the animal into contact with innately specified needs, such as food, shelter,
and water. The emotions operate on faster time-scales and regulate the relation of the
animal with its (often social) environment. An active emotional response can be thought of
as temporarily seizing control of the behavior system to force the activation of a particular
observable response in the absence of other contributing factors. By doing so, the emotion
addresses the antecedent conditions that evoked it. Emotions bring the animal close to things
that benefit its survival, and motivate it to avoid those circumstances that are detrimental to
its well-being. Emotional responses are also highly adaptive, and the animal can learn how
to apply them to new circumstances.
Overall, motivations add richness and complexity to an animal’s behavior, far beyond a
stimulus-response or reflexive sort of behavior that might occur if only perceptual inputs
were considered, or if there were a simple hardwired mapping. Motivations determine the
internal agenda of the animal, which changes over time. As a result, the same perceptual
stimulus may result in a very different behavior. Or conversely, very different perceptual
stimuli may result in an identical behavior given a different motivational state. The motiva-
tional state will also affect the strength of perceptual stimuli required to trigger a behavior. If
the motivations heavily predispose a particular behavior to be active, a weak stimulus might
be sufficient to activate the behavior. Conversely, if the motivations contribute minimally, a
very strong stimulus is required to activate the behavior. Scherer (1994a) discusses the ad-
vantages of having emotions decouple the stimulus from the response in emotive reactions.
For members in a social species, one advantage is the latency this decoupling introduces
between affective expression and ensuing behavioral response. This makes an animal’s
behavior more readable and predictable to the other animals that are in close contact.
Behavior Groups

Up to this point, I have taken a rather simplified view of behavior. In reality, a behavior to
reduce hunger may be composed of collections of related behaviors. Within each group,