So, you think that because you’ve seen one milksnake you’ve seen them all? Think again.
Recent research has identified up to seven distinct species within the genus Lampropeltis. Some milksnakes have tri-color patterns similar to those of venomous coral snakes. Researchers suspect it’s a way to ward off predators by advertising toxic species’ warning signals, a phenomenon known as Batesian mimicry.
But since milksnakes—which inhabit a large geographic region that includes northeast Canada, the United States, Central America, and even parts of Ecuador, Colombia, and Venezuela—have also been found in areas where coral snakes do not occur, researchers have a second hypothesis for their coloring: flicker-fusion.
Brightly banded in reds, blacks, and yellows, these snakes’ distinctive patterns are hard to miss when the animal is motionless. But once it begins to swiftly slither, its bands blend together. The movement creates an optical illusion making the snake hard to spot against the background of its usual natural environment in tall grasses or the forest floor. And when it freezes, for just a moment, it seems to disappear almost completely.
“This theoretically confuses the predators as they lose sight of the position of the snake,” says Frank Burbrink, associate curator in the Museum’s Department of Herpetology. “This may play in tandem with the Batesian mimicry of the venomous snake when the jig is up.”
It’s an adaptation that might even be more efficient than mimicking a more dangerous animal. After all, predators can’t eat you if they can’t see you.
A version of this story originally appeared in the Spring 2018 issue of Rotunda, the Member magazine.