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    Ermittlung von Lernkapazität, Generalisationsvermögen und Gedächtnisdauer des Kanadischen Bibers mit Hilfe der simultanen Zweifachwahl (1995)

    Art
    Hochschulschrift
    Autor
    Schroeder, Daniela
    Quelle
    Berlin, 1995 — 119 Seiten
    Kontakt
    Institut für Tierschutz und Tierverhalten

    Königsweg 67
    Gebäude 21, 1. OG
    14163 Berlin
    +49 30 838 62901
    tierschutz@vetmed.fu-berlin.de

    Abstract / Zusammenfassung

    Aim of this study was to judge the efficiency of the beaver brain with the aid of the parameters learning capacity, generalisation ability and memorizing duration. Its performance is compared to that of marsupials" brains Two Canadian beavers were offered patterns in the simultaneous double tat. These patterns corresponded exactly to those used in similar tests on wombats by MICHAEL (1987) The tests were carried out over a span of 12 months. Test animal I learned ten pattern pairs in 3090 trial runs, test animal 2 equally learned ten pattern pairs in 3060 trial runs. The learning behaviour was strongly influenced by the individual motivation. Motivating test animal 2 was very difficult at the beginning of the trials, but it became more concentrated during the course of the tests and was consistent in its learning accomplishments. Test animal I always participated well as it was a very greedy animal, but it was not very concentrated in the final trials. This animal had two litters during the time of the tests, which had to be suckled and can be regarded as external interference factors. When learning the pattern pairs the beavers comprehended shape differentiations to different degrees. Test animal I learned pattern pairs with a strong differentiation in shape more easily than those that differed only slightly in shape. Test animal 2 on the other hand had problems in learning the "bigger - smaller" task (pattren pair 9). Presentation of the pattern pairs in the multiple tests (following the double test, all pattern pairs learned until then mixed but the last pair learned) lead to the result that the animals did not accomplish the 9 times multiple test in 81,1 % (test animal 1) and in 84,4 % (test animal 2) of the cases. With the help of neutral directors the animals were offered just one of the patterns of a pair at atime. This was supposed to show wether the animals had learned the two patterns of a pair separately or just the pair as such. Test animal I had learned the pattern pairs in the combination offered only, test animal 2 can be assumed to have mastered all of the twenty separate patterns. M the patterns according to a horizontal impression. They nsanage ingle components of an original pattern pair, but had problerns recogtii en these had been rotated within the sarne plane (example: "oblique crc erfical ar angement). The thresnold to a high generalization level (3. Ievc ~n according to RENSCH and D?CKER 1959) was reached partly, ization tests took place 20 days after the last generalization test. . ^ offered pattern pairs in 3 Tirnes multiple sirnultaneous tests on tn {s. There was a break of ten days between these tests. Test animal I did ] 1 of significance in any of tne mernorization tests, test animal 2 was alwa al run 1, above the significance level.The results of the generalization tesb lead to the condusion that the beavers differentiated tne patterns according to a horizontal impression. They managed to recognize single components of an original pattern pair, but had problems recoBliizing patterns wben tbese had been rotated within the same plane (exarnple: "oblique cross", squares in vertical arrangement). The tbresbold to a high generalization level (3. level of generahzation according to RENSCH and D?CKER 1959) was reached partly. The memorization tesb took place 20 days atier the last generalization test. The animals were offered pattern pairs in 3 Times rnultiple simultaneous tests on tbree following days. There was a break of ten days between these tests. Test animal I did not reach the level of significance in any of the memorization tests, test anirnal 2 was always, apart from trial run 1, above the significance level. - 112 The results of the generalization ests lead to the conclusion that the beavers differentiated the patterns according to a horizontal impression. They managed to recognize single components of an original pattern pair, but had problems recognizing patterns when these had been rotated within the same plane (example: "oblique cross", squares m vertical arrangement). The threshold to a high generalization level (3. Ievl of generahzation according to RENSCH and D?CKER 1959) was reached partly. The memorrzation tests took place 20 days after the last generalization test. The animals were offered pattern pairs in 3 Times multiple sirnultaneous tests on three following days. There was a break of ten days between these tests. Test animal I did not reach the level of significance in any of the memorization tests, test animal 2 was always, apart from trial run 1, above the significance level.