The two most recent posts have focused on Nikolaas Tinbergen because he was one of the scientists who contributed most to the earliest theories about ethology, which eventually led to matters often discussed by Dr. Pretlow, like displacement behavior.
Tinbergen asked questions about animal behavior that no one else had thought about. Most academics at the time were in the habit of doing research at their own convenience, on animals who had been removed from natural environments and sequestered in labs, in utterly foreign and uncongenial circumstances. But what could be the value of knowledge gained from subjects in captivity, deprived of every vestige of their accustomed lives?
In the field
Particularly fascinated by birds and insects, Tinbergen reckoned he would learn more by going out to where the animals were, living the way nature intended. Rather than ripping creatures from their supportive environments and traumatizing them into abnormal states, his concept of a reasonable experiment was to change a single factor and see what happened.
His observations, although made in the natural setting, were nonetheless systemic and even elegant. Although less rigid than those of by-the-book investigators, his methods paradoxically managed to tease out truths that had been either ignored or deprecated. This paragraph is typical of the things written about him:
One set of (now well-known) field experiments there was aimed at the analysis of the pecking response gull chicks directed at their parents’ bills (thus eliciting food regurgitation): which colors, bill shapes, and movements could make the chicks peck. It was published in Behaviour in 1950; it could be criticized in its methods, but the innovative approach opened new avenues in biology.
In 1936 Tinbergen met up with Konrad Lorenz, who was destined to become another giant in the area of ethology:
Lorenz’s early scientific contributions dealt with the nature of instinctive behavioral acts, particularly how such acts come about and the source of nervous energy for their performance. He also investigated how behavior may result from two or more basic drives that are activated simultaneously in an animal.
Together they experimented with…
[…] cardboard models that were pulled overhead over young goslings and turkeys… The models resembled a bird of prey (short neck, long tail) when pulled in one direction, and a duck when pulled in the other. The goslings responded as the investigators expected, reinforcing the idea of a very simple set of stimuli that directs behavior.
In 1942, Tinbergen published “An Objectivistic Study of the Innate Behaviour of Animals,” which suggested that the internal and external causes of animal behavior can be ranked in a hierarchical fashion. For instance, the reproductive drive is at the top, and then splits into sub-drives like nest-building, courting, or fighting. In this scheme, different drives were seen to be mutually exclusive:
All such behavior patterns would be inherited and innate, and he referred to them as “stereotyped movements” (later “fixed action patterns”), each set off by a release mechanism that was triggered by a specific stimulus.
(To be continued…)
Your responses and feedback are welcome!
Source: “Tinbergen, Nikolaas (Niko),” Encyclopedia.com, 06/27/18
Source: “The Study of Instinct — work by Tinbergen,” Britannica.com, undated
Image by Brian Ralphs/CC BY 2.0