高冠三鳍鱼在红色过滤器下呈现红色荧光色（右图），在自然光线下呈现暗灰色（左图）
据美国生活科学网报道，目前，科学家发现许多鱼类喜欢红色调，一些鱼类身体表面真实具有活力色调的荧光色。
负责此项研究的德国图宾根大学尼科·米切尔斯称，到目前为止，许多研究人员都认为水上生物世界中并不是很欢迎红色，海水面上能够直接吸收阳光中的红色波长。根据阳光波长对海水的渗透性，意味着在空气中物体更易成为红色、在浅水中物体更易成为灰色、在33英尺以下的水面物体更易成为黑色。不像红色，蓝绿色光可以渗透至海面以下更深处，这就是为什么海洋看起来很蓝。
但是近期的研究发现显示，鱼类有呈现红色调的独特方法。米切尔斯说，“这项最新研究结果将发表在最新出版的《BMC生态学》杂志上，该研究显示红色荧光普遍存在于海洋鱼类之中。”
米切尔斯在红树林海湾和红海之间潜水时意外地发现一种身体发出红色荧光的鱼，这种鱼被称为“高冠三鳍鱼”(highcrest triplefin fish)，在这片海域他深入分析了如何深红色光渗透进入水中。他戴上潜水镜从而确保自己仅能看到红色光，他发现这种奇特红色荧光鱼有独特之处——其眼圈旁有红色斑点，红色荧光照亮了全部身体或覆盖着鱼鳍。
米切尔斯说，“给人印象最深的就是眼圈周围的红色荧光，它的身体就像是被完全照亮。”他指出，这种红色荧光很可能是一种秘密通信或吸引注意力的信号。但是确切的原因尚未证实。这是由于红色荧光是来自鱼的身体，并非来自经水面过滤后的光线，这种鱼发出的红色荧光在海度深处可清晰地看到，但只有到近距离时才能看清它的真实面目。他告诉美国生活科学网站，“我们确信这是第一次在海域中发现这种红色荧光鱼，现将它作为一种珊瑚鱼类中一个重要的现象特征。”
据悉，许多鱼类都显示出具有蓝色和绿色荧光的能力，2005年，一种水母被确定可散发出红色荧光。散发荧光的现象通常是由于吸收了光线中的一种波长，然后以另一种非常接近的波长释放，这种红色荧光鱼吸收了光线中的蓝绿色波长，再释放出红色波长。
米切尔斯猜测红色荧光在珊瑚和其他鱼类中是一种普遍现象，由于这项首次发现，他还在地中海发现其他多种释放不同颜色荧光的鱼类。（生物谷Bioon.com）
生物谷推荐原始出处：
BMC Ecology 2008, 8:16doi:10.1186/1472-6785-8-16
Red fluorescence in reef fish: a novel signalling mechanism?
Nico K. Michiels , Nils Anthes , Nathan S. Hart , Juergen Herler , Alfred J. Meixner , Frank Schleifenbaum , Gregor Schulte , Ulrike E. Siebeck , Dennis Sprenger and Matthias F. Wucherer
Abstract (provisional)
Background
At depths below 10 m, reefs are dominated by blue-green light because seawater selectively absorbs the longer, 'red' wavelengths beyond 600 nm from the downwelling sunlight. Consequently, the visual pigments of many reef fish are matched to shorter wavelengths, which are transmitted better by water. Combining the typically poor long-wavelength sensitivity of fish eyes with the presumed lack of ambient red light, red light is currently considered irrelevant for reef fish. However, previous studies ignore the fact that several marine organisms, including deep sea fish, produce their own red luminescence and are capable of seeing it.
Results
We here report that at least 32 reef fishes from 16 genera and 5 families show pronounced red fluorescence under natural, daytime conditions at depths where downwelling red light is virtually absent. Fluorescence was confirmed by extensive spectrometry in the laboratory. In most cases peak emission was around 600 nm and fluorescence was associated with guanine crystals, which thus far were known for their light reflecting properties only. Our data indicate that red fluorescence may function in a context of intraspecific communication. Fluorescence patterns were typically associated with the eyes or the head, varying substantially even between species of the same genus. Moreover red fluorescence was particularly strong in fins that are involved in intraspecific signalling. Finally, microspectrometry in one fluorescent goby, Eviota pellucida, showed a long-wave sensitivity that overlapped with its own red fluorescence, indicating that this species is capable of seeing its own fluorescence.
Conclusions
We show that red fluorescence is widespread among marine fishes. Many features indicate that it is used as a private communication mechanism in small, benthic, pair- or group-living fishes. Many of these species show quite cryptic colouration in other parts of the visible spectrum. High inter-specific variation in red fluorescence and its association with structures used in intra-specific signalling further corroborate this view. Our findings challenge the notion that red light is of no importance to marine fish, calling for a reassessment of its role in fish visual ecology in subsurface marine environments.
