IRENAUS EIBL-EIBESFELDT 67 



The distinction between innate and acquired behaviour patterns, there- 

 fore, is not at all an artificial one. If a male salticid spider needed to learn 

 by trial and error his complicated courtship display, which enables him 

 to approach the cannibalistic female, he woulci get eaten before copula- 

 tion. A newborn baby, unable to suckle, would starve before having 

 learned the complicated pattern of movements. On the Galapagos 

 Islands no carnivorous land mammal exists and therefore many of the 

 endemic birds have lost their escape reaction. They are tame, with just a 

 few exceptions. One such exception is the little endemic Galapagos Dove 

 [Ncsopclia (^alapai^ociisis) which shows 'injury feigning'. As soon as one 

 approaches a nest with nestlings, the adult bird flutters from the nest to 

 the ground. There it runs away from the nest, fluttering its widespread 

 wings. This "injury feigning' is well known in birds of other countries, 

 where its function is to attract the attention of a predator and to lead him 

 from the nest. But on Galapagos there arc no carnivorous mammals, 

 and the behaviour pattern is normally not used. It seems rather difficult, 

 therefore, to explain this behaviour on the basis of the learning hypothesis. 

 From where might the animal have gathered the information about 

 predators, to which its behaviour is adapted ? Since the information could 

 not have been acquired during the ontogeny of the individual, the only 

 remaining possibility is that this information was acquired by the species 

 during the course of evolution, at a time when it was confronted with 

 predators; this 'experience' must have been preserved in the genoma of the 

 species. It appears in the Galapagos Dove as a behavioural relict. 



In the normal behaviour of an animal, innate and acquired patterns are 

 closely linked together into functional units, so that it is very often rather 

 difficult to distinguish the two components from each other. Nevertheless, 

 we can deprive an organism of special information and thereby prove that 

 certain behaviour patterns are innate. Doves (Grohmann, 1939) and 

 swallows (Spalding, 1873) for example have been reared under conditions 

 that made it impossible for them to use their wings and practise flying 

 movements. Upon being released, however, these animals were able to fly 

 as well as their siblings, who had not been deprived of the opportunity to 

 learn flying. 



How independently from learning processes certain behaviour patterns 

 develop, can also be seen in mallards reared in isolation. With the onset of 

 sexual maturity they will show such highly differentiated movements as 

 grunt whistle and head-up-tail-up, without ever having seen another 

 mallard. If we raised a tufted drake or a mandarin drake under identical 

 conditions we should observe them performing their species specific 



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