Personality and learning in chicks : Gallus gallus domesticus

Abstract

Det har vært en økende interesse innenfor atferdsøkologien for å studere personlighet hos dyr. Tidligere studier som har undersøkt matsøk og aposematisme hos kyllinger(Gallus gallus domesticus) har vist store individuelle forskjeller i iveren etter å prøve ny mat og neophobia. Jeg ønsket å undersøke dette nærmere ved å teste unge kyllingers læreevne knyttet til mat i tillegg til en rekke personlighetstester som alle måler fryktrespons, med hypotesen om at fryktløse kyllinger har en læringsfordel i forhold til fryktsomme individer.

There has been a growing interest within the field of behavioural ecology for studying animal personality. Previous studies investigating food search and aposematism in chicks of the common chicken (Gallus gallus domesticus) have shown great individual differences in eagerness to try new food and neophobia. I wanted to investigate this further by testing young chicks learning abilities related to food in addition to a number of personality tests that all measure fear response, with the hypothesis that fearless chicks have an advantage in learning compared to fearful individuals. In 8 successive rounds of training 60 two-day old chicks were taught to find tasty mealworms that were hidden under brown roof shaped cardboard pieces, first in pairs to avoid stress, then individually. During the following experimental trials half of the mealworms were taste manipulated with quinine and mustard powder and hidden under either green or yellow (aposematic) cardboard roofs in addition to the brown control roofs. Half the chicks were tested with control and green roofs, the other half with control and yellow roofs, in order to see if aposematism affects their learning. The aim was to test if the chicks were able to learn that yellow or green roofs signalled unpalatability. One experimental trial consisted of four coloured roofs interspersed with four control roofs. After 12 experimental trials the chicks were tested for their capability to re-learn the meaning of green/yellow roofs by hiding palatable mealworms only under the different coloured roofs. After the learning experiment, the chicks were subjected to the following personality tests that all measure the chicks fear response in different situations: Open Field Test, Response To A Bell Test, Hole In The Wall Box Test, and The Foreign Object Test. The aim was to separate „fearful‟ chicks from „brave‟ chicks and test for a correlation with their learning abilities, to test the hypothesis that brave chicks would dare to eat more and thus learn what was palatable and not.