Image courtesy of Nanfang Yu, Columbia Engineering
a) Scanning electron microscopy image of the hair coating of Saharan silver ants, which shows the triangular cross section of the hairs. The cross section was produced using focused ion beam milling. The uniquely shaped hair coating strongly reflects sunlight and efficiently dissipates heat through thermal radiation. b) Upper images: Photographs of the abdomen of a silver ant before and after hair removal. Lower image: A graph of the transient temperature of the specimens as a function of time. The data show that the specimen with intact hair coating can maintain a reduced steady-state temperature when exposed to the solar spectrum. The specimen with intact hairs also possesses a smaller time constant for temperature change, which indicates a larger rate of thermal radiation (a larger rate of cooling) due to the presence of the hair coating.