| Summary: | The way in which most animals sense and interpret the environment around them differs from species to species. Even two closely related species such as the red-crowned parakeet (Cyanoramphus novaezelandiae) and the Antipodes Island parakeet (C. unicolor) may respond to the same stimulus in very different ways. Individual birds can also show different personality traits or temperament phenotypes when presented with a novel environment. Despite being closely related, the two species used in this study have evolved in different natural habitats and use different foraging strategies. The Antipodes Island parakeets are naturally found on a group of sub-Antarctic islands known as the Antipodes Islands where they live in the tussock and sledge fields that cover the large islands and feed on the grasses and other vegetation. The red-crowned parakeets can be found on the small remnants of podocarp forests around New Zealand where they can be seen living in the canopy and on the forest floor, where they feed on mostly fruits, flowers and berries with a small proportion of invertebrates. I postulated that the evolutionary selection pressures on these two species will have resulted in differing behaviour and sensory physiology that could be measured in an experimental setting. Five individuals from each species was presented with four options in four different sensory experiments (sound, taste, colour and smell). The four different options were presented on top of a metal pole that was placed in each corner within a 1m3 perspex box. The behaviours shown by the birds over each 20-minute testing period was recorded and analysed in terms of both sensory preferences and personality traits. Each sensory experiment was repeated four times with each of the 10 birds. This mean that each bird was tested a total of 16 times (four repeats for each of the four sensory tests). The Antipodes Island parakeets showed interest in all four sensory experiments and spent time investigating all of the options presented to them, but showed the ...
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