2025-06-26 カリフォルニア大学アーバイン校(UCI)
Digital camera images of the entire body (top left) and dorsal mantle (top right) of a squid show the splotches’ blue, green, yellow, orange and red iridescent (angle-dependent) colors. An individual splotch (bottom, from left) transitions from transparent to red to orange to green at 0, 60, 90 and 120 seconds, respectively, when subjected to chemical and neurophysiological stimuli. Gorodetsky lab / UC Irvine
<関連情報>
- https://news.uci.edu/2025/06/26/uc-irvine-led-team-uncovers-cell-structures-that-squids-use-to-change-their-appearance/
- https://www.science.org/doi/10.1126/science.adn1570
勾配屈折率がイカの構造色を可能にし、マルチスペクトル材料にインスピレーションを与える Gradient refractive indices enable squid structural color and inspire multispectral materials
Georgii Bogdanov, Aleksandra Anna Strzelecka, Nikhil Kaimal, Stephen L. Senft, […] , and Alon A. Gorodetsky
Science Published:26 Jun 2025
DOI:https://doi.org/10.1126/science.adn1570
Editor’s summary
Squids and octopuses are known for their rapid adaptive coloration, an ability that enables them to effectively camouflage and that is also used for communication. Bogdanov et al. performed a detailed examination of the cells (iridophores) and cell clusters (splotches) that produce these colors (see the Perspective by Shawkey). There was a complex distribution of cells and other components that exhibit gradient refractive indices arising from their constituent winding platelet columns, resulting in structural color. Computational modeling of this system supported the design of artificially fabricated nanostructures that show tunable visible and infrared spectral responses. The authors implemented these structures in complex materials such as fabric and clothing. —Marc S. Lavine
Abstract
The manipulation of light by means of materials with varying refractive index distributions is widespread among natural systems and modern technologies. However, understanding how animals leverage refractive index differences for dynamic color changes and then translating such insight into tunable optical devices remains challenging. We experimentally and computationally demonstrated that iridescent cells (iridophores) containing Bragg reflectors with sinusoidal-wave (rugate) refractive index profiles enable squid dorsal mantle tissues to reversibly transition between nearly transparent and vibrantly colored states. We then drew inspiration from these findings for the design and development of iridophore-inspired multispectral composite materials with tunable visible and infrared functionalities. Our study provides insight into squid dynamic structural coloration mechanisms and furnishes a technology for camouflage, heat management, display, and sensing applications.
