Of the many Lepidopteran pokemon, Vivillon have proved by far the most successful, having spread from Kalos to virtually every region of the world. In doing so, they have become among the most varied of known pokemon species, with a diversity of form matching that of Arceus. This was once believed to be an example of clinal variation, with different varieties having evolved separately to adapt their beautiful patterns to provide camouflage from the poles to the tropics, and many old science textbooks use these pokemon as a demonstration of evolution.
Yet Vivillon in recent years have finally been successfully bred in captivity, with results that turned the traditional understanding of this pokemon on it's head. A Vivillon's colors do not necessarily emulate either parent, but are chosen at birth to best camouflage themselves within the region where they hatched. Scatterbug and Spewpa from abroad will evolve into their foreign color, but the children of foreign Vivillon will inevitably assimilate into the coloration of the natives.
What Vivillon have evolved is not an example of how pokemon within a common species can differ in color based on geographic barriers, like a more dramatic parallel to Shellos or Man, but an ability to adapt to their habitat on an individual level which far succeeds anything ordinary biological evolution can muster. Since this discovery, researchers have begun to study the Vivillon intensely, in the hopes of unlocking the secret to this ability – one which offers to enhance science's understanding of color, and allow a far greater self-customization ability for humans and pokemon alike than even the marvelous, varied fashions of Kalos can allow. And perhaps even more importantly, it should allow us to analyze climate through the ages, for Vivillon patterns have not been wholly static even during Man's limited written history.