I will always try to get a photograph whenever I see a Monarch Butterfly, as I noted in a recent post, so I immediately set out after this orange and black butterfly when I spotted it on Monday at Occoquan Bay National Wildlife Refuge. When the butterfly landed and I got a closer look, I discovered that it was a Viceroy butterfly (Limenitis archippus), a species considered to be a mimic of the Monarch. The two species share similar color schemes, but the Viceroy is smaller and has a black line across its hind wings that in not present on Monarch wings.
I had learned long ago that Viceroys used a type of defensive behavior, known as Batesian mimicry, in which a palatable species, the Viceroy, closely resembles unpalatable or toxic species, like the Monarch, to avoid predation. However, some research suggests that the Viceroy is also unpalatable, which would make the Viceroys and Monarchs co-mimics of each other, a phenomenon known as Müllerian mimicry, in which two or more noxious species develop similar appearances as a shared protective device.
In the abstract of his article entitled “Comparative unpalatability of mimetic viceroy butterflies (Limenitis archippus) from four south-eastern United States populations” David Ritland stated, “Viceroy butterflies (Limenitis archippus), long considered palatable mimics of distasteful danaine butterflies, have been shown in studies involving laboratory-reared specimens to be moderately unpalatable to avian predators. This implies that some viceroys are Müllerian co-mimics, rather than defenseless Batesian mimics, of danaines.” (Monarch butterflies (Danaus plexippus) are part of the Daniadae sub-family (“danaine”) that Ritland mentioned.) Ritland tested his hypothesis with wild-caught butterflies and red-winged blackbirds and the results supported his hypothesis that Viceroys are unpalatable.
I have no idea what scientists have concluded about the mimicry question regarding the Viceroy butterfly, but it is fascinating to see the interrelatedness of different species that share this planet. We are all in this together.
© Michael Q. Powell. All rights reserved.
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