|Milkweed Tussock cats - Kelly Bigbee|
In the photograph above, a Monarch caterpillar is hanging below the leaf with a Tussock Moth on top. Chris Barnhart noted that the Tussock Moth seems to mimic the Monarch cat in both coloration and size when you account for the mass of hairs.
Since birds tend to avoid Monarchs because of the milkweed toxin in their bodies, could this be a case of Batesian mimicry, using its similar appearance to warn off predators by pretending to be a toxic Monarch cat? Actually it is even more complicated. The Milkweed Tussock Moth also stores the milkweed cardiac glycoside toxins. This is an example of Müllerian mimicry, where two or more insects with the same toxic chemicals display similar color patterns to warn off predators.
|Gregarious Tussock Moth caterpillars stripping a milkweed leaf - Chris Barnhart|
These Tussock Moth caterpillars are gregarious, with multiple individuals feeding on the same leaf. They can afford this exposure because if one of their siblings is eaten, the bird will soon be too busy upchucking to come back for seconds.
|Milkweed Tussock Moth Patrick Coin|
|After eating a monarch butterfly- Dr. Lincoln Brower|
*Observation made by Barb's sister who is a connoisseur of Lutheran potluck suppers.