Our topic today is the Oriental hornet, Vespa Orentalis. For some time, scientists had know that the workers of this species were most active towards the middle of the day. It was only recently that they confirmed that they are capable of directly harvesting solar power. Under very close examination (on the nanometer scale), the brown segments of the hornet's abdomen are a series of reflective mirrors. They reflect the sun's energy onto structures on the yellow part of the abdomen, which contains a pigment with photoelectric properties, thus turning the light into electrical energy, which the hornets then use for their activities.
Story and picture courtesy of the BBC. Plenty more details, including microscope scans of the hornet's skin.