An Exception To The Rule
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I’ve been featuring a lot of images lately of animals that survive in our desert in part because they are so well camouflaged. It seems as if the majority of species has, through trial, error, and evolution, hit upon the cloak of invisibility as a survival strategy. I assure you, there will be more of these in days to come.
Tonight, however, I’m going to take a break from the camouflage artists and show a species that is an exception to the rule that camouflage is essential for survival. Indeed, this species has adopted the opposite strategy, relying on its brilliant coloration to ward off predators. This is the Pipevine Swallowtail Butterfly.
Pipevine Swallowtails are among the showiest creatures that we see in our desert. Their brilliant cobalt blue bodies patterned with white spots are a signature for this species, as are the bright orange and white circular marking on the underside of these butterflies’ wings (the upper wings are cobalt blue). It’s almost as if these insects are trying to advertise something to would-be predators.
Indeed, they are. Pipevine Swallowtails get their name from the fact that their larvae feed exclusively on the vegetation of the Pipevine plant and related species. These plants are highly toxic. The Pipevine caterpillars and adult butterflies are immune to the plants’ toxins and the caterpillars can happily munch away on Pipevines with impunity. However, the plant toxins permeate the tissues of the caterpillars and the adult butterflies and these insects wind up becoming as toxic as are the plants that the caterpillars feed on.
So, the brilliant colors sported by the adult butterfly are a way of asserting: “don’t mess with me, I’m poisonous.” Predators eat this species at their peril.
Photo taken with a Canon 5Diii, 180 f3.5 L Macro Lens assisted by Canon 600EX-RT Speedlite, ISO 125, f18 @ 1/160.