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TPO 4 Lecture 1 Biology
Narrator
Listen to part of a lecture in a biology class. The class is discussing animal
behavior.
Professor
Ok, the next kind of animal behavior I want to talk about might be familiar to
you. You may have seen, for example, a bird that’s in the middle of a mating
ritual, and suddenly it stops and preens, you know, takes a few moments to
straighten its feathers, and then returns to the mating ritual. This kind of
behavior, this doing something that seems completely out of place, is what we
call a ‘Displacement Activity’. Displacement activities are activities that
animal’s engaging in when they have conflicting drives. If we take our example
from a minute ago, if the bird is afraid of its mate, it’s conflicted. It wants to mate but it’s also afraid and wants to run away. So, instead, it starts grooming itself. So, the displacement activity, the grooming, the straightening of its feathers, seems to be an irrelevant behavior. So, what do you think another example of a displacement activity might be?
Karl
How about an animal that, um, instead of fighting its enemy or running away, it
attacks a plant or a bush?
Professor
That’s really good suggestion, Karl. But that’s called ‘redirecting’. The animal is redirecting its behavior to another object, in this case, the plant or the bush. But that’s not an irrelevant or inappropriate behavior. The behavior makes sense. It’s appropriate under the circumstances. But what doesn’t make sense is the object the behavior‘s directed towards. Ok, who else? Carol?
Carol
I think I read in another class about an experiment where an object that the
animal was afraid of was put next to its food – next to the animal’s food. And
the animal, it was conflicted between confronting the object and eating the
food, so instead, it just fell asleep. Like that?
Professor
That’s exactly what I mean. Displacement occurs because the animal’s got two
conflicting drives – two competing urges, in this case, fear and hunger. And
what happens is, they inhibit each other, they cancel each other out in a way,
and a third seemingly irrelevant behavior surfaces through a process that we
call ‘Disinhibition’. Now in disinhibition, the basic idea is that two drives that seem to inhibit, to hold back, a third drive. Or, well, they’re getting in a way of each in a… in a conflict situation and somehow lose control, lose their inhibiting effect on that third behavior, which means that the third drive
surfaces, it’s expressed in the animal’s behavior. Now, these displacement
activities can include feeding, drinking, grooming, even sleeping. These are
what we call ‘Comfort Behavior’. So why do you think displacement activities
are so often comfort behaviors, such as grooming?
Karl Maybe because it’s easy for them to do? I mean, grooming is like one of the most accessible things an animal can do. It’s something they do all the time, and they have the stimulus right there on the outside of their bodies in order to do the grooming, or if food is right in front of them. Basically, they don’t have to think very much about those behaviors.
Carol
Professor, isn’t it possible that animals groom because they’ve got messed up
a little from fighting or mating? I mean if a bird’s feathers get ruffled or an
animal’s fur, maybe it’s not so strange for them to stop and tidy themselves up at that point.
Professor
That’s another possible reason although it doesn’t necessarily explain other
behaviors such as eating, drinking or sleeping. What’s interesting is that
studies have been done that suggest that the animal’s environment may play a
part in determining what kind of behavior it displays. For example, there’s a
bird, the ‘wood thrush’, anyway, when the ‘wood thrush’ is in an attack-escape conflict, that is, it’s caught between the two urges to escape from or to attack an enemy, if it’s sitting on a horizontal branch, it’ll wipe its beak on its perch. If it’s sitting on a vertical branch, it’ll groom its breast feathers. The immediate environment of the bird, its immediate, um, its relationship to its immediate environment seems to play a part in which behavior will display.