Continuous and discrete quantity discrimination in tortoises

From “sense of number” to “sense of magnitude”: The role of continuous magnitudes in numerical cognition

(2016) Tali Leibovich et al.   BEHAVIORAL AND BRAIN SCIENCES

Numerosity representations in crows obey the Weber–Fechner law

(2016) Helen M. Ditz et al.   PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES

Quantity discrimination by zebrafish (Danio rerio).

(2015) Davide Potrich et al.   JOURNAL OF COMPARATIVE PSYCHOLOGY

Numerical discrimination by frogs (Bombina orientalis)

(2014) G. Stancher et al.   ANIMAL COGNITION

Bears ‘count’ too: quantity estimation and comparison in black bears, Ursus americanus

(2012) Jennifer Vonk et al.   ANIMAL BEHAVIOUR

Evidence for Two Numerical Systems That Are Similar in Humans and Guppies

(2012) Christian Agrillo et al.   PLoS One

Visual and response-based navigation in the tortoise (Geochelone carbonaria)

(2009) Anna Wilkinson et al.   ANIMAL COGNITION

Arithmetic in newborn chicks

(2009) R. Rugani et al.   PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES