Before looking at earlier writings about displacement, there are some interesting points in a relatively recent (1967) assessment of the situation from psychologist/zoologist Juan D. Delius. At the time, it was taken for granted that animal displacement activities arose from three scenarios: “motivational conflict, frustration of consummatory acts and physical thwarting of performance.”
Dr. Delius wrote that “no binding rules exist by which displacement behavior can be recognized.” In general, displacement comes into discussion of “behavior patterns which appear to be out of context with the behavior which closely precedes or follows them…”
Precedes or follows — that covers a lot of ground!
If an enemy threatens, and a bird flies away, it is reasonable to conclude that there is a connection. It is seen as cause and effect, “in context” with the previous event, the perception of a threat. Whether the bird continues to fly for a while, or immediately lands on a branch — wouldn’t either one of those choices be equally in context with what came before — i.e., the flying off?
If an enemy threatens, and a bird starts to preen itself, this is seen by humans as displacement behavior, a way of discharging nervous energy through arbitrary activity, because for some reason flight is not an option, and neither is fighting or other possible actions that might actually be useful in averting the threat.
This may be where unjustified anthropomorphism comes into the picture. Human judgment might cloud the understanding of another, as-yet-unrealized truth. One point is, preening is not the same for birds as for humans. The bird isn’t just checking its teeth for lipstick smears, or tossing a lock of hair aside. Preening is essential maintenance, a combination of cleaning, pest removal, waterproofing, and other necessary chores. If the feathers are not in good order, flying might be impossible — a serious consequence.
Okay, says the human, so it’s not just fiddling, it’s important survival-oriented behavior. But the timing is inappropriate. An enemy is poised to pounce. This failure to defend oneself, or to at least remove oneself from the scene, is looked upon by humans as aberrant.
An open question?
But with what rationale? Maybe the animal has good and sufficient reasons to try out this tactic. Maybe it hears some inner voice: “Pick your battles. Try distraction. Try waiting out the clock. Try hoping that the enemy is so dim, it will forget it was even looking at you.” Many creatures have been getting along for millennia without human opinions, operating on criteria that humans would perhaps condemn as poor judgment. Maybe we don’t know everything about why animals do the things they do.
Dr. Delius said another thing that seems to deserve more attention than perhaps has been granted:
None of the theories on displacement activities gives cogent reasons why particular behavior patterns should be more common than others as displacement activities, apart from stating that the causal agents which usually elicit them in non-displacement situations can also be presumed to be present, if only weakly, in the displacement context, or remarking that these patterns are prepotent in the repertoire of the animal.
The phrase, “the causal agents which usually elicit them in non-displacement situations” seems meaningful, and connected to the idea that preening, for instance, is not just a silly distraction, but an activity that is quite ordinary and vital to the bird’s existence. Just possibly, it is not for humans to judge whether he is doing it at the right time, or not. Possibly, this is what the author meant by saying that “no binding rules exist by which displacement behavior can be recognized.”
Your responses and feedback are welcome!
Source: “Displacement Activities and Arousal,” Nature.com, 06/17/67
Image by Emmy Silvius/CC BY-ND 2.0
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