all pokémon are actually ditto
pokémon are all born as ditto and then they decide what kind of pokémon they want to be but some of them can't pick and so they just floof around as amorphous blobs or whatever suits their mood
i'm samus the inventor of pokémon and this is canon
@onethousandtwentyfour Were there other Pokémon at some point? Otherwise, how do they keep falling into a few hundred district types?
@aschmitz the types are like fashions
they change over time but it's easier for ditto to change into a known form, so they tend to copy each other's styles than just come up with something completely new
however some pokémon, like trubbish, are pretty recent actually