According to the Backyard Brains website, the Longfin Inshore has "three different chromatophore colors: brown, red, and yellow. Each chromatophore has tiny muscles along the circumference of the cell that can contract to reveal the pigment underneath."
And the best way to demonstrate the changing colors: hip-hop. The researchers attached the cephalopod to an electrode hooked up to an iPod nano, and let rip the Cypress Hill tune "Insane in the Brain."
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