Pokemon Fans Are Still Debating the Venomoth and Butterfree 'Swapped' Theory

gamerant.com:

Countless obscure details and fun pieces of trivia left over from the Gen 1 Pokemon games have fueled fan theories for nearly three decades now, with one popular theory regarding a certain evolutionary line still being subject to debate from fans to this day. While quite a few of the creature designs seen throughout the Pokemon series have sparked the idea of them originally being designed to fit into a different evolution family altogether, there's one particular example that stands out.

Pokemon evolution has been observed since the concepts of these creatures and the Pokemon world in general were first introduced. The vast majority of Pokemon species are able to evolve, often drastically changing their appearance and stats by doing so. The evolutionary links between some Pokemon species aren't immediately obvious though, and while it's fairly easy to recognize that Charmander is related to Charmeleon, for example, other species such as Magikarp would likely take newer fans of the franchise by complete surprise when it evolves into the vicious sea serpent that is Gyarados.

With there now being more than 1,000 unique species of Pokemon altogether, some creatures invariably end up sporting features that look like they've been adapted from other species. This is an especially crucial detail to keep in mind when considering the design constraints and typically simple appearances of most Pokemon, but even so, many longtime fans of the franchise have likely heard of the theory that suggests Butterfree and Venomoth are «swapped» evolutions — or in other words, that Venomoth was originally designed to evolve from Metapod, and Butterfree was supposed to evolve from Venonat. An infographic post shared online by the user invertposting helps to demonstrate the similarities these Pokemon share.

The mirroring of the coloring, eyes, antennae, mouth, and overall body shape between Venonat and Butterfree has long led fans to believe that these species were meant to share the same