I have noticed a very small hummingbird sucking nectar from a basket of wishbone flowers near my back door. Watching it closely, I realized that it was not a bird but a type of hawk moth, Macroglossum stellatarum, or a hummingbird hawk moth. Because it has a long proboscis and hovers near blossoms, making a definite humming sound, it is easily mistaken for a tiny bird.
Hummingbird hawk moths have brown wings with black striations in the front, and orange wings outlined with black in the back. Its body has more depth and breadth than is common to an insect, another feature that makes it appear bird-like. Its wingspan is less than two inches, and the wings move at such a speed as to appear nearly invisible.
Entomologists have studied the visual acuity of these moths extensively. Apparently, the hummingbird hawk moth shows the ability to learn colors. They can be seen flying anytime of the day. Once they discover a flower bed or hanging basket, they will return to it at the same time each day.