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bioRxiv · 10.1101/2021.02.15.431186

Rapid active-reflection display on dorsal stripes of Atherinomorus lacunosus

Iwasaka, M.
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Abstract

A large number of living creatures are able to use environmental light effectively as a biological display. The biological structural colors are very attractive not only within the coloring species but also to humans. However, the detailed function of bio-reflectors, which constitute the structural color with respect to communication, remains unknown. Atherinomorus lacunosus has alignments of iridophore spots on its dorsal part. Here it is found that a spot with a diameter of approximately 0.1 mm causes a rhythmic blinking of light owing to rapid reflection changes in iridophores existing inside the spot. The iridophores contain reflecting particles which show similar rotational responses to magnetic field under a light exposure. The speed of the intensity change of light at a frequency of approximately 1 Hz is proposed to be controlled by the nervous system of A. lacunosus. This kind of passive illumination may contribute to the development of a new optical device with low energy consumption.

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Iwasaka, M.. 2021-02-16. Rapid active-reflection display on dorsal stripes of Atherinomorus lacunosus. https://doi.org/10.1101/2021.02.15.431186

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