Colour discrimination and associative learning in hatchling lizards incubated at ‘hot’ and ‘cold’ temperatures
The ability of an animal to acquire, process and learn from information in their environment is thought to be fundamental to fitness. We currently have a poor understanding of the learning ability of young animals within the first few months of their life, the types of learning they use and the extent of their learning ability. Furthermore, an animal’s developmental environment, such as nest incubation temperature, may profoundly influence motor and cognitive skills. We first tested the ability of hatchling three-lined skinks (Bassiana duperreyi) incubated at ‘hot’ and ‘cold’ temperatures to solve an instrumental (motor) task before assessing their ability to learn colour associations in a multi-stage instrumental task, with a choice reversal. While 53 (88.3 %) lizards successfully completed the training phase, 14 (46.7 %) of the ‘hot’ incubated and none of the ‘cold’ incubated lizards successfully completed the instrumental task. Thirteen of these lizards rapidly learnt to discriminate colours, and this culminated in eight individuals successfully completing a choice reversal. Hatchling B. duperreyi demonstrated surprisingly rapid learning, and these results highlight the potentially important role of cognition during development and ultimately, in fitness.
KeywordsCognition Incubation Choice reversal Motor task
Funding of this study was from Australian Research Council to RS, Natural Sciences and Engineering Research Council of Canada to JJA and DWAN, and a Macquarie University internal grant to BFC and MJW. We thank the reviewers for their constructive criticism of our study.
All work was carried out under the approval of the Animal Ethics Committee of the University of Sydney (ARA 5361) in agreement with the Animal Ethics Committee of Macquarie University.
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