Background & Aims

Gentoo penguins (Pygoscelis papua) present four types of single cones containing light sensitive pigments (SWS1, SWS2, RH2 and LWS), however colour vision can be impaired by various factor, such as light intensity and background colouration and can be altered by evolution. Moreover, all penguins species present a non-functional RH2 gene (which is responsible for the green-light sensitive pigments), making them trichromatic. Nevertheless, they present coloured traits, which role is not fully understood, that suggest that colour vision plays a role in their ecology. The present study is the first to behaviourally study colour vision in penguins.