Behaviour 2019
Quantity Discrimination of an Asian Freshwater Turtle (Geoemydidae: Mauremys sinensis)
Feng-Chun Lin1, Pei-Jen Lee Shaner1, Ming-Ying Hsieh2, Si-Min Lin1. 1School of Life Science, National Taiwan Normal University, Taipei, , Taiwan; 2The Thinking Dog Vet Behaviour Service, Taipei, , Taiwan

Quantitative ability plays a key role in foraging, mating, and defense. Diverse fish, birds, and mammals had been proved their numerical abilities; yet there exists a profound gap of this knowledge in reptiles. In this study, we aimed to investigate the numerical capabilities of an Asian freshwater turtle (Mauremys sinensis) by using training procedures. Through a sequential training of increased ratio according to Weber's law, turtles established the "greater than" concept which was further applied on unfamiliar quantities. We then assessed their numerical performance with diverse ratios and differences, and further approached the numerical limitation of this species. Our results demonstrated that turtles successfully discriminate up to 9 versus 10, which is comparable to, and has only been discovered in great apes. The numerical performance was affected by the ratio of the two quantities, which supports Weber’s law. This is one of the first study using training procedure to investigate quantity discrimination across small and large numbers in turtles, providing evident learning ability in in reptiles, and indicating that the intelligence of reptiles is underestimated.