Drawing on the well-documented preference for natural and highly biodiverse environments in humans, it has been proposed that other animals may also recognise and show interest in natural stimuli. If widespread across animals, such a preference could have important evolutionary and welfare implications. However, we currently lack investigations of this preference outside humans. To begin filling this gap, we examined whether juvenile guppies (Poecilia reticulata) exhibit a spontaneous preference for natural stimuli. In a dichotomous choice test, guppies were given the opportunity to choose between an environment containing live aquatic plants and one with structurally similar, in shape and size, artificial plants. After habituation to the testing apparatus, guppies spent significantly more time in the environment with live plants, suggesting a preference for natural stimuli. This supports the idea that, beyond humans, other animals may also be capable of recognizing and responding to natural stimuli.
Varracchio et al. (Thu,) studied this question.