Veille Scientifique

Abstract Aggressive behaviour in fishes, particularly in territorial species, is a common trait used to defend resources such as food or mates. Territorial males of the Mediterranean parrotfish Sparisoma cretense have been described to chase away conspecifics yet other aggressive behaviour repertoire has not been reported for this species. We describe, for the first time, an extreme aggressive behaviour between two male Mediterranean parrotfish which includes biting and prolonged mouth locking.

Ethology, EarlyView.

Ethology, EarlyView.

Abstract Eastern gray squirrels (Sciurus carolinensis) exhibit a variety of color morphs, including black. In the USA and UK, a common folk belief is that black squirrels are more aggressive than squirrels of other colors. We tested the biological basis of that belief using data from the 2018 Central Park squirrel census. Contrary to the belief, black squirrels do not chase other squirrels more often than do conspecifics of other colors. Black and non-black squirrels were equally likely to approach people for food and to display indifference to human presence, but black squirrels were more likely than non-black squirrels to

Abstract Many plant species have seeds embedded in their fleshy pulp to attract frugivores, which enhances the chance of seed dispersal. However, some tropical plants are evolved with sharp spines ...

Abstract The midsession reversal paradigm confronts an animal with a two-choice discrimination task where the reward contingencies are reversed at the midpoint of the session. Species react to the reversal with either win-stay/lose-shift, using local information of reinforcement, or reversal estimation, using global information, e.g. time, to estimate the point of reversal. Besides pigeons, only mammalian species were tested in this paradigm so far and analyses were conducted on pooled data, not considering possible individually different responses. We tested twelve kea parrots with a 40-trial midsession reversal test and additional shifted reversal tests with a variable point of reversal. Birds

Ethology, EarlyView.

Abstract Species of scorpionfly (Mecoptera) in the family Panorpidae perform wing-waving behaviors, whereby they rotate their front and rear wings at the same time. Previous studies have suggested that a ...

Abstract We trained eight pigeons (Columba livia) on a stagewise go/no-go visual discrimination task. A total of 16 visual stimuli were created from all possible combinations of four binary dimensions: brightness (dark/bright), size (large/small), line orientation (vertical/horizontal), and shape (circle/square). In the first stage, we presented S + and four S– stimuli: sharing one (brightness), two (brightness and orientation), three (brightness, orientation, and size), or no dimensional values with S + . In the second stage, all 16 stimuli were presented. In the first stage, stimulus discrimination was controlled by the number of dimensional disparities between non-rewarded stimuli and a rewarded one rather than

Abstract Responses to mirrors vary in non-human animals. Many species respond socially to mirrors with relatively few species demonstrating self-recognition in mirrors. In this study, we investigated the responses of ferrets to mirrors. Six adult ferrets (3 males, 3 females, all over a year old) were exposed to mirrors and their responses were investigated over three experimental conditions (baseline, mirror preference, mark test) in a repeated measures design. Upon initial presentation, the ferrets showed more approach and sniffing behaviour toward the mirror than the non-reflective surface. The ferrets also showed a preference for the mirror and spent more time in