Today I will explain a little about this terminology that few know, let's begin:
Ethology is the branch of biology and experimental psychology that studies the behavior of animals in the environment in which they are found, either in a situation of freedom or under laboratory conditions, although field studies are better known. When studying especially the behavior in the natural environment, ethological research is distinguished from behavioral research, centered on the artificial or laboratory environment.
The naturalistic approach to the understanding of animal behavior must have a long history or, better said, prehistory, for Paleolithic man and hunter, at least in its utilitarian aspect. The behavior of more or less monstrous or divine animals was also part of several mythologies of antiquity, in which the subjects in question developed such different behaviors as suckling future kings, preying on different heroes and even mating with goddesses, humans and nymphs . However, the very comprehension of animal behavior took a long time for man to seriously consider it. For the majority of the Greco-Latin philosophers, man was an isolated entity and, far from that stellar role, animals were mere comparsas whose behavior did not deserve great attention.
The theological system proposes man as the only being capable of distinguishing good from evil through the use of his reason. Behaving according to this criterion, each human could save or condemn his immortal soul. Since animals would not have a soul and could not, therefore, preserve it after death, the possession by them of the gift of reason would be unnecessary. The animals would be limited to obey mechanically to an instinct donated to each individual by a creator, an instinct that would guarantee their survival.
Darwin (1871, 1872) takes the first steps in coming out of that vicious circle by basing his conclusions mainly on the facts, since for him the behavior, the morphology and the physiology are integrated into the baggage of adaptations that allow individuals survive and reproduce. In addition, when the idea of discontinuity in the evolution of the mind was discarded in the evolutionary proposal, it was not necessary to take man as a reference, since it was also assumed that his behavior was derived from that shown by his animal ancestors. Also, reproductive behavior is an integral part of the process by the formulation of sexual selection, dependent on the competition between males and the choice of these by females. However, the broad field that Darwin opened with his theory of natural selection had no immediate consequences on the understanding of behavior. The first Darwinists did not know how to get rid of the old instinct-reason dichotomy and insisted on looking for instinctive behaviors in man and rational behaviors in animals, thus preventing a development consistent with the idea of continuity implicit in evolutionary theory.
An important nuance to the model of the Innate Triggering Mechanism is that often the signals, although simple, must keep certain spatial relationships, that is, they must function as configurational stimuli as seen in the following image:
On the left we can see models used in the triggering of the attack on the spiny fish. In figure A (fish shape and uniform color) is rarely attacked, while rudimentary models with red bottom (B) are intensely attacked. On the right we have models used to trigger the petition in blackbird chickens (A and B).
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