Chapter

Evolution of Color Vision in Vertebrates

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  • The International University of Beirut
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Abstract

Color vision provides organisms with important sensory information about their environment. For instance, the ability to distinguish colors allows organisms to detect and recognize two very important objects—food and mates. What colors animals can detect will influence their ability to forage and hunt, avoid predators, and select quality mates. The basic biological mechanisms, on which vertebrate color vision ultimately rests, the cone opsin genes and the photopigments, are highly conserved. Within that constraint, however, the utilization of these basic elements varies in striking ways in that they appear, disappear and emerge in altered form during the course of evolution. These changes, along with other alterations in the visual system, have led to profound variations in the nature and salience of color vision among the vertebrates. In any case, perhaps the major strength of primate color vision comes not just from the keenness of their discrimination abilities, which are considerable, but rather from the fact that primates have evolved a large, agile and plastic brain that allows them to use color information in a multitude of ways generally unavailable to those species with more limited central processing capability. This chapter concerns the evolution of color vision among the mammals, viewing that process in the context of relevant biological mechanisms, of variations in mammalian color vision, and of the utility of color vision.

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... A large number of excellent reviews on the rhodopsin families have been published, many of which we have referred to where appropriate, along with the most relevant early and recent papers. We refrain from presenting many molecular details, and therefore we refer to the following more recent reviews (DeGrip and Rothschild, 2000;Hofmann, 2000;Spudich et al., 2000;Hofmann et al., 2009;Yizhar et al., 2011;Palczewski and Orban, 2013;Ernst et al., 2014;Imamoto and Shichida, 2014;Inoue et al., 2014;Deisseroth, 2015;Hofmann and Palczewski, 2015;Brown and Ernst, 2017;Bando et al., 2019;El Khatib and Atamian, 2019;Dowling, 2020;Kandori, 2020;Kwon et al., 2020;Baillie et al., 2021;Moraes et al., 2021;Rozenberg et al., 2021;Bondar, 2022;Broser, 2022;Brown, 2022;Khelashvili and Menon, 2022;Nagata and Inoue, 2022). ...
... Vertebrate cone pigments cover the entire visible spectrum, and can be divided into four subsets, the longwavelength (LWS, absorbance maximum range 520-640 nm), green (Rh2, 460-530 nm), blue (SWS2, 400-470 nm), and UV (SWS1, 350-450 nm) sensitive pigments (Crescitelli, 1991;Yokoyama and Yokoyama, 2000;Imamoto and Shichida, 2014). This classification is not only based upon spectral sensitivity, but also upon sequence similarity (Nathans, 1987;Hunt and Collin, 2014;Jacobs, 2018;El Khatib and Atamian, 2019). Invertebrate visual pigments are more scattered over the visible region and can range from 340 nm up to 600 nm (Gärtner, 2000;Katz and Minke, 2009;Tsukamoto and Terakita, 2010). ...
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Chapter
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Visual ecology or the relationship between the visual system of an animal and its environment has proven to be a crucial research field for establishing general concepts of adaptation, specialization and evolution. The visual neuroscientist is indeed confronted with a plethora of different visual characteristics, each seemingly optimised for each species' ecological niche, but often without a clear understanding of the evolutionary constraints at play. However, before we are able to fully understand the influence(s) of ecology and phylogeny on visual system design in vertebrates, it is first necessary to understand the basic bauplan of key representatives of each taxa. This review examines photoreception in hagfishes, lampreys, cartilaginous fishes and lungfishes with an eye to their ecology using a range of neurobiological methods including anatomy, microspectrophotometry and molecular genetics. These early vertebrates represent critical stages in evolution and surprisingly possess a level of visual complexity that is almost unrivalled in other vertebrates.
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The organism, a physico-chemical entity, co-exists in delicate balance with its environment. This is manifested not only by external, morphological modifications, but also by structural and physiological changes expressed at tissue and cellular levels. These changes may be divided into two categories:- the first represents a gradual process such as, for example, a unicellular organism evolving into a multicellular one (increase in efficiency); while the second represents a more rapid form of “evolution” whereby an organism adapts to its environment by modifications of preexisting structures (adaptive radiation). With respect to vision, light (radiation) is the single-most important factor contributing to retinal changes. These changes may, in some instances be rapid enough to be manifested during the life time of the organism, although they may be temporary and revert to the original form once the stimulant is removed.
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It is hypothesized that colour vision and opponent processing of colour signals in the visual system evolved as a means of overcoming the extremely unfavourable lighting conditions in the natural environment of early vertebrates. The significant flicker of illumination inherent in the shallow-water environment complicated the visual process in the achromatic case, in particular preventing early detection of enemies. The presence of two spectral classes of photoreceptors and opponent interaction of their signals at a subsequent retinal level allowed elimination of the flicker from the retinal image. This new visual function provided certain advantages concerning reaction times and favoured survival. This assumption explains why the building blocks for colour vision arose so early, i.e. just after the active predatory lifestyle was mastered. The principal functions of colour vision inherent in extant animals required a more complex neural machinery for colour processing and evolved later as the result of a change in visual function favouring colour vision.
Color Perception in a Dichromate
  • Roth Lina
  • Almut Kelber
  • Anna Balkenius
Roth Lina S, Almut Kelber, Anna Balkenius. Color Perception in a Dichromate. The Journal of Experimental Biology. 2007; 210:2795-2800.
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Goldsmith Timothy H. What Birds See. Scientific American. 2006; 294:68-75.
Visual communication based on color signals in aquatic environments
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  • D Meuthen
Rick P, Meuthen D. Visual communication based on color signals in aquatic environments. Institute for Evolutionary Biology and Ecology, University of Bonn, Germany, 2012.