Perception and discrimination of movement and biological motion patterns in fish

Abstract

Vision is of primary importance for many fish species, as is the recognition of movement. With the exception of one study, assessing the influence of conspecific movement on shoaling behaviour, the perception of biological motion in fish had not been studied in a cognitive context. The aim of the present study was therefore to assess the discrimination abilities of two teleost species in regard to simple and complex movement patterns of dots and objects, including biological motion patterns using point and point-light displays (PDs and PLDs). In two-alternative forced-choice experiments, in which choosing the designated positive stimulus was food-reinforced, fish were first tested in their ability to distinguish the video of a stationary black dot on a light background from the video of a moving black dot presented at different frequencies and amplitudes. While all fish succeeded in learning the task, performance declined with decreases in either or both parameters. In subsequent tests, cichlids and damselfish distinguished successfully between the videos of two dots moving at different speeds and amplitudes, between two moving dot patterns (sinus vs. expiring sinus) and between animated videos of two moving organisms (trout vs. eel). Transfer tests following the training of the latter showed that fish were unable to identify the positive stimulus (trout) by means of its PD alone, thereby indicating that the ability of humans to spontaneously recognize an organism based on its biological motion may not be present in fish. All participating individuals successfully discriminated between two PDs and two PLDs after a short period of training, indicating that biological motions presented in form of PLDs are perceived and can be distinguished. Results were the same for the presentation of dark dots on a light background and light dots on a dark background.

Visual Discrimination of Geometric and Complex 2D Shapes in Goldfish (Carassius auratus)

“…We should use caution in interpreting results from few subjects because within-species differences between fish can occur (Gierszewski et al, 2013;Lucon-Xiccato, Dadda, & Bisazza, 2016;Miletto Petrazzini & Agrillo, 2016;Schluessel et al, 2012Schluessel et al, , 2015Siebeck et al, 2009;Wyzisk & Neumeyer, 2007). However, other studies have utilized two to five goldfish per experiment or test (Douglas, Eva, & Guttridge, 1988;Freche et al, 2012;Neumeyer, 1992Neumeyer, , 2003Wyzisk & Neumeyer, 2007).…”

“…We used a series of geometric and complex shapes similar to stimuli used by Siebeck et al (2009) to test shape learning and discrimination in the reef damselfish Pomacentrus amboinensis. It is uncommon to see the performance of more than one fish species compared on the same task using the same stimuli (cf, McAroe, Craig, & Holland, 2016;Schluessel, Kortekamp, Ortiz Cortes, Klein, & Bleckmann, 2015). Past studies have used different methods to test fish, including the 'correction method' (Mackintosh & Sutherland, 1963, Wysik & Neumeyer, 2007 and the 'non-correction method' (Experiment 5 in Siebeck et al, 2009;Sovrano & Bisazza, 2008).…”

Behavioral color vision in a cichlid fish: Metriaclima benetos

“…Cichlids are quite adaptable and several species seem amenable to training under laboratory conditions. Cichlids have shown that they are able to recognize facial cues between conspecifics (Satoh et al, 2016), and Lake Malawi Metriaclima species have been used for shape discrimination, object categorization and symmetry perception tasks (Schluessel et al, 2012(Schluessel et al, , 2014(Schluessel et al, , 2015.…”

Determining the Role of Hand Feeding Practices in Accidental Shark Bites on Scuba Divers

“…In addition, feeders often attract the attention of the shark by shaking the hand holding the food. In two alternative forced-choice experiments, in which choosing the designated positive stimulus was food-reinforced, it was recently shown that fish are able to distinguish biological motion patterns [23]. Therefore, the hand shaking associated with food reward can be considered as a strong visual stimulus for the sharks.…”