A collaborative research group consisting of Assistant Professor Chihiro Hiramatsu of the Graduate School of Arts and Engineering, University of Kyushu, Assistant Professor Amanda Melin of the Faculty of Anthropology, University of Calgary, and Assistant Professor James Higham of the Faculty of Anthropology, University of New York, has a "three-color color vision" that primates identify colors. For the first time, we have experimentally proved that it is effective for humans to distinguish complexion.
Many primates, including humans, see the world with "three-color color vision" that discriminates the wavelength of light by three pyramidal photoreceptor cells (L, M, and S).This "three-color color vision" is thought to have evolved from the ancestral two-color color vision because it is suitable for finding red fruits and young leaves from the background of green leaves.
However, since there may be situations where "three-color color vision" is effective other than finding fruits, it is necessary to conduct a wide-ranging investigation in light of the behavior and ecological significance of primates. Detection of social signals such as changes in complexion has been cited as a candidate for situations where "three-color color vision" is effective.
Therefore, the collaborative research group decided to experimentally investigate whether the "three-color type color vision" of primates is suitable for detecting complexion changes.Using photographs of rhesus monkeys whose faces turn red during the breeding season, we asked human participants to distinguish between female breeding and non-breeding faces by simulating the appearance of various color visions.As a result, the "three-color type color vision" in which the wavelength sensitivity of the L and M cones possessed by primates is biased to the long wavelength range is suitable for detecting minute differences in red, and changes in complexion are well detected. I found that I could do it.
This result confirms that the detection of social signals is one of the adaptive significances of "three-color color vision", and it is also primates that humans can read emotions from their complexion and detect their health condition. It is thought that it is due to such color vision characteristics that it has.In the future, it is expected to approach the process of adaptive evolution of primate color vision, such as at what stage of primate evolution the change in complexion began to be used as a social signal.
This paper was published in the online version of the academic journal "Bulletin of the Royal Society of the United Kingdom" on June 2017, 6 (British summer time).
Paper information:[Proceedings of the Royal Society of London B] Experimental evidence that primate trichromacy is well suited for detecting primate social color signals
