Mood Bugs: Beetle changes color in fluid fashion

Color-changing animals, such as chameleons and squid, typically alter their hues when nerve signals or hormones spur pigment cells in their skin to expand or shrink.

COLOR ME BEETLE. The 8-millimeter-long golden tortoise beetle uses shell structures, rather than pigmented cells, to dramatically change color. Main image and top inset show reflective-gold state, which progresses to matte red at bottom.