Quantity discrimination in the eastern water skink (Eulamprus quoyii)

Quantity discrimination is a cognitive ability that allows vertebrates to process discrete and continuous numerical information. Amphibians and non-avian reptiles have long been underestimated regarding studies of cognition and, as a result, have limited studies investigating their quantity discrimination abilities. This thesis contains two chapters: a systematic literature review chapter and a data chapter. The systematic literature review summarises the currently published literature about quantity discrimination in amphibians and non-avian reptiles. Within this chapter, I discuss the literature on quantity discrimination in amphibians and non-avian reptiles and compare this to other vertebrates. I also identify gaps in our knowledge and suggest future avenues for research. The data chapter focuses on a binary choice experiment to investigate how the eastern water skink uses quantity discrimination. I used images of crickets displayed on an iPad screen that varied in number or size to determine if the skinks could discriminate between different ratios. I found that the skinks could only discriminate treatments with the lowest ratio of 0.25. However, these results show that they can perform quantity discrimination and demonstrate a novel approach to studying quantity discrimination in non-avian reptiles through the use of digital stimuli.