Italian

 

Giuseppe Merandino

Liceo Scientifico Enrico Boggio Lera, Catania, Italia

 

In this article I would like to explain how Ethology was influenced by the study of Evolution, without it, in fact, it would have been impossible to formulate those principles that are the basis of this discipline, as the classification of animal species and their adaptation to the environment. We could not use the term Ethology if we did not consider the theses of evolution as the growth factor of this subject; Ethology spread with the Evolution, otherwise Ethology wouldn’t have sense, so it is fundamental.

Ethology is that part of Zoology which studies the behaviour of animals, we can say it provides some answers to certain stresses from the environment, so to whatever stimulus, a new behaviour corresponds performed in a totally mechanical way, without the use of the intellect. The first scientist who gave great contribution to Ethology was Jean Baptiste Lamarck, who studied evolution. He was the first to speculate that animals, including Homo Sapiens, descended from other species; he stated the genetic heredity of acquired characters, so that acquired characteristics were inheritable; for example he thought that a bodybuilder could transmit his musculature to his children. This hypothesis was disassembled by the scientist Charles Darwin who, 50 years later, presented a new Theory on Evolution and on genetic inheritance more reliable than Lamarck’s. Darwin stated that the cause of Evolution did not depend only on environmental adaptation, but it also depended on sometimes random genetic mutations that, in time, determined morphological changes in a species; it was up to nature to select only organisms that could live in

conditions dictated by the environment; this process is called Natural Selection. In the following years there were further discoveries which brought interest for Ethology on higher levels. Skinner formulated a lot of important theories about Ethology; he emphasized that there is a learning mechanism in whatever animal which can be defined as by trial and error; behaviours followed by a prize or by a reward tend to be repeated and retained, while those followed by a punishment, on the contrary, tend to decrease not to be repeated in future. This procedure performed instinctively was called Operating Conditioning. Skinner showed the validity of the term with some tests carried in his laboratory: he inserted some mice inside special cages called Skinner Box built by him, where there was a lever that, when pressed, gave a piece of cheese to the animal. In the first tests the mice acted randomly and moving here and there they accidentally pressed the lever; repeating the tests a number of times, they started to associate the gesture of pressing the lever to the delivery of a reward.

The true initiator of Ethology, also considered as the father of this discipline, is certainly Lorenz Konrad; when he was 6 he had the opportunity to observe that wonderful event of Imprinting, a term coined by himself; it is a learning mode of vertebrate in which the animal concerned is particularly impressionable by the first moving object it sees, coming to associate to the latter a mother figure. Lorenz since young was so attracted by the wild geese that he would have raised one; not given the opportunity, he contented himself with a duck he bought as a chick, it became attached to the scientist who spent long time with it during the period of imprinting or during the 36 hours subsequent the hatching of the egg. Konrad also explained how some animals perform certain actions mechanically; he explained that a wild goose that, whenever one of its egg slid away from the nest, collected it with a precise movement of its beak; this movement also was performed if to completed is the egg was removed during the process.

 

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