This is another remarkable photograph—and biology lesson—from Alex Wild’s great website Myrmecos. If you have any interest in nature photography or insects, it will pay you to bookmark it and check the site regularly.
There are many flies—as well as lepidopterans—that have evolved to resemble wasps and bees, fooling predators that have either evolved or learned to avoid that sting-inducing black-and-yellow pattern. Such cases (and you should know this by now) are called Batesian mimicry, after the naturalist H. W. Bates, who first described the phenomenon whereby an edible species (the “mimic”) evolves to resemble a toxic, dangerous, or distasteful “model,” fooling the predator (the “signal receiver”) into avoiding the mimic.
No, not a bee eating a bee. Even better! This is a bee-mimicking robber fly, Laphria, feeding on a honey bee. The fly casually alighted next to me in the garden this afternoon, as though it wanted to be photographed with a trophy kill.
Laphria is an exemplary bumble bee mimic. The flies not only look like bumble bees, they move and sound like them as well.
I was once fooled by a wasp-mimicking moth when I lived in Maryland. Seeing what looked like a stinging insect on the inside of my window, I carefully caught it with my Drosophila net. When I found out it was a mimic and not in the least dangerous, I was embarrassed!
Here’s a clear-winged moth from FotoLog; I’m not sure of the species, nor whether it’s the one I saw in Maryland, but the resemblance between members of two insect orders (Lepidoptera and Hymenoptera) is remarkable—look at those stripes!