Fairy wrasses perceive and respond to their deep red fluorescent coloration

Abstract

Fluorescence enables the display of wavelengths that are absent in the natural environment, offering the potential to generate conspicuous colour contrasts. The marine fairy wrasse Cirrhilabrus solorensis displays prominent fluorescence in the deep red range (650–700 nm). This is remarkable because marine fishes are generally assumed to have poor sensitivity in this part of the visual spectrum. Here, we investigated whether C. solorensis males can perceive the fluorescence featured in this species by testing whether the presence or absence of red fluorescence affects male–male interactions under exclusive blue illumination. Given that males respond aggressively towards mirror-image stimuli, we quantified agonistic behaviour against mirrors covered with filters that did or did not absorb long (i.e. red) wavelengths. Males showed significantly fewer agonistic responses when their fluorescent signal was masked, independent of brightness differences. Our results unequivocally show that C. solorensis can see its deep red fluorescent coloration and that this pattern affects male–male interactions. This is the first study to demonstrate that deep red fluorescent body coloration can be perceived and has behavioural significance in a reef fish.

Naturally occurring fluorescence in frogs

“…The identification of additional hyloin analogs was assisted with molecular networking (19), which grouped related parent ions in different clusters based on similarities in MS/MS fragmentation patterns. The resulting clusters allowed the identification of compounds of the homologous series based on systematic fragmentation studies considering the MS/MS spectra of the isolated hyloins ( different lengths (10)(11)(12) and degrees of unsaturation (0−2) of the side chain (Fig. 3D) were detected in crude lymph and epidermal samples (SI Appendix, Fig.…”

Ultraviolet and yellow reflectance but not fluorescence is important for visual discrimination of conspecifics by Heliconius erato

“…Several studies have concluded that fluorescence is an important component of complex signals in aquatic animals because of the contrast between narrow-band down-welling blue light and longwavelength fluorescence (Mazel et al, 2004;Gerlach et al, 2014). However, the evidence that fluorescence contributes to signaling in terrestrial animals, where the illumination spectrum is broadband, is much more limited and somewhat mixed.…”

Method for Determining the Contribution of Fluorescence to an Optical Signature, with Implications for Postulating a Visual Function

“…Much of this has focused on origin and possible ecophysiological roles of the fluorescing proteins in reef corals (Salih et al, 2000;Kelmanson and Matz, 2003;Ugalde et al, 2004;Bou-Abdallah et al, 2006;Palmer et al, 2009;Gittins et al, 2015;Smith et al, 2017), but some studies have touched on possible visual functions in fish and other marine organisms (Mazel et al, 2004;Haddock et al, 2005;Matz et al, 2006;Michiels et al, 2008;Gerlach et al, 2014;Sparks et al, 2014;Haddock and Dunn, 2015;Gruber et al, 2016). A few of these latter have had a strong foundation in measurement and analysis, while others have been more speculative and suggestive, based purely on observation and correlation.…”

“…It can be extremely difficult to set up experimental conditions that eliminate the fluorescence while not affecting other visual factors at the same time but this has been done for several cases (Arnold et al, 2002;Gerlach et al, 2014;Haddock and Dunn, 2015).…”