Like many others settling in for a Friday night movie with a side of snacks, I opted for Doritos chips. My perception of Doritos has always been associated with quality, but after reading the long list of ingredients for one particular flavor (Bold Barbeque), I completely lost my appetite. The flavor, which I expected to be a premium product, was instead loaded with foreign ingredients that seemed out of place. Among them, I identified at least two food coloring agents, but a third one caught me off guard – Indigotine. Intrigued by the word itself, I knew instinctually that it had something to do with color indigo, so I did some more research.

My initial hunch connecting it to the color indigo turned out to be accurate; indigotine (shown be ...

Bats have an uncanny ability to track and eat insects on the fly with incredible accuracy. But some moths make these agile mammals miss their mark. Tiger moths (left), for example, emit ultrasonic clicks that jam bat radar. Now, scientists have shown that hawk moths (right) and other species have also evolved this behavior. The nocturnal insects - which are toxic to bats - issue an ultrasonic "warning" whenever a bat is near. After a few nibbles, the bat learns to avoid the noxious species altogether. Interestingly, the sound-producing apparatus is typically located at the tip of the moth's genitals. ...