Colour discrimination and associative learning in hatchling lizards incubated at ‘hot’ and ‘cold’ temperatures
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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.
- Burghardt GM (1977) Learning processes in reptiles. In: Gans C, Tinkle DW (eds) Biology of the Reptilia, vol 7, Ecology and Behaviour A. Academic Press, London, pp 555–681Google Scholar
- Chapillon P, Patin V, Roy V, Vincent A, Caston J (2002) Effects of pre- and postnatal stimulation on developmental, emotional, and cognitive aspects in rodents: A review. Dev Psychobiol 41:373–387Google Scholar
- Coomber P, Crews D, Gonzalez-Lima F (1997) Independent effects of incubation temperature and gonadal sex on the volume and metabolic capacity of brain nuclei in the leopard gecko (Eublepharis macularius), a lizard with temperature-dependent sex determination. J Comp Neurol 380:409–421PubMedCrossRefGoogle Scholar
- Cooper W, Greenberg N (1992) Reptilian coloration and behavior. Biol Reptil 18:298–422Google Scholar
- Halpern M (1992) Nasal chemical senses in reptiles: structure and function. In: Gans C (ed) Biology of the Reptilia: hormones, brain, and behaviour, vol 18, Physiology E. Chicago University Press, Chicago, pp 423–523Google Scholar
- Harlow PS (1996) A harmless technique for sexing hatchling lizards. Herpetol Rev 27:71–72Google Scholar
- Noble DWA, Carazo P, Whiting MJ (2012) Learning outdoors: male lizards show flexible spatial learning under semi-natural conditions. Biol Lett 8:946–948Google Scholar
- Rice D, Barone S Jr (2000) Critical periods of vulnerability for the developing nervous system: evidence from humans and animal models. Environ Health Persp 108(Suppl 3):511–533Google Scholar
- Shettleworth SJ (2009) Cognition, evolution, and behavior. Oxford University Press, New YorkGoogle Scholar
- Shine R (2004a) Incubation regimes of cold-climate reptiles: the thermal consequences of nest-site choice, viviparity and maternal basking. Biol J Linn Soc 83:145–155Google Scholar
- Shine R (2004b) Does viviparity evolve in cold climate reptiles because pregnant females maintain stable (not high) body temperatures? Evolution 58:1809–1818Google Scholar