In 1861, Henry Bates first offered a theory that insects use mimicry to fool predators. He noticed that some edible insects shared the same coloration as other unpalatable species. Because predators learned to avoid insects with these color patterns, he argued, the mimics gained protection by displaying the same warning colors. This form of mimicry came to be called Batesian mimicry.
Almost 20 years later, German naturalist Fritz Müller offered a different example of insects using mimicry. He observed communities of similarly colored insects, all unpalatable to predators, and theorized that these insects all gained protection by displaying the same warning colors. Should a predator eat one insect with a certain coloration and find it inedible, it will learn to avoid catching any insects with similar coloration.
Müllerian mimicry rings may arise, in which multiple insect species from different families or orders share common warning colors. When a mimicry ring includes many species, the probability of a predator catching one of the mimics increases. While this may seem disadvantageous, it's actually quite the opposite. The sooner a predator samples one of the unpalatable insects, the sooner it will learn to associate the colors of that insect with a bad experience.
What are some examples of Müllerian mimicry? At least a dozen Heliconius butterflies in South America share similar colors and wing patterns. Each member of this longwing mimicry ring benefits, as predators learn to avoid the group as a whole. If you've ever grown milkweed in your garden, you've probably noticed the surprising number of insects on your milkweed plants that share the same red and black colors. These beetles and true bugs represent another Müllerian mimicry ring.