Mate choice and body pattern variations in the Crown Butterfly fish Chaetodon paucifasciatus (Chaetodontidae)

Abstract

Mate choice is an important ecological behavior in fish, and is often based on visual cues of body patterns. The Crown Butterfly fish Chaetodon paucifasciatus (Chaetodontidae) is a monogamist, territorial species; it swims in close proximity to its partner throughout most of its life. This species is characterized by a pattern of 6–8 vertical black stripes on a white background, on both sides of its body. Our aim was to define spatial features (variations) in body patterns by evaluating the level of dissimilarity between both sides of each individual fish, and the level of dissimilarity between patterns of different individuals. In addition, we tested whether the fish are attracted to or reject specific features of the body patterns. Features were defined and counted using photographs of body patterns. Attraction to or rejection of specific features were tested behaviorally using a dual-choice experiment of video animations of individuals swimming over a coral-reef background. We found that the patterns of each fish and sides of the body were no less dissimilar, compared intraspecificly to other fish, and that each side pattern was unique and distinguishable. Variations in the patterns occurred mostly in the last three posterior stripes. Individuals were mainly attracted to conspecifics with multiple crossing patterns (two or more consecutive crossings), and rejected patterns with holes. Our results suggest that in this species the unique body pattern of each fish is used for conspecific identification of mates and intruders.

Three-dimensional computer graphic animations for studying social approach behaviour in medaka fish: Effects of systematic manipulation of morphological and motion cues

“…For example, body pattern features of the crown butterfly fish [51] and zebrafish [39] can be used for conspecific identification of mates. The shape of the tail fin affects behavioural response to conspecifics in swordtail fish [52] and bettas [53].…”

A computer vision for animal ecology

“…For example, to correctly outline a flying bird, algorithms might look for the areas where the wings intersect with the sky (Atanbori, Duan, Murray, Appiah, & Dickinson, 2016). Image features have been primarily used to study the evolutionary ecology of animal coloration (Stoddard, Kilner, & Town, 2014), shape (Lavy et al, 2015) and patterning (Levy, Lerner, & Shashar, 2014). Compared to human review, computer vision provides a more consistent way to score animal appearance across images by using non-RBG colour spaces, such as HSV or YChCr, which are less sensitive to changes in illumination and other image artefacts (Kühl & Burghardt, 2013;Troscianko, Skelhorn, & Stevens, 2017).…”

Modifying twisted nematic LCD screens to create dichromatic visual stimuli with LEDs

“…The use of computers to present animations/videos in the study of visually guided behaviours has been instrumental in understanding the interaction of complex traits and behaviour, for instance through the manipulation of the morphology and movement patterns of computer generated animals (Chouinard‐Thuly et al, ; Clark, Kizer Zeeff, Karson, Roberts, & Uetz, ; Hebets & Uetz, ). Typically, these stimuli are presented to animals using LCD screens (How, Pignatelli, Temple, Marshall, & Hemmi, ; Levy, Lerner, & Shashar, ; Stewart, Kinoshita, & Arikawa, ; Van Hamme, Wasserman, & Biederman, ), which are able to create a wide array of colours using mixtures of three differently coloured lights (Red, Green, Blue [RGB]). The relative intensity required to produce a specific colour is based on extensive psychophysical experimentation in humans (Richardson, ).…”