i disbelieve that cubone is really a baby kangashan.the reason being there are many loop holes in this theory, that i would like to point out.all tho there are many examples that can explain this,i want to pinpoint 3 KEY examples that i think will represent this theory to be flawed.one example of this is cubone is wearing an unknown skull,thats said to be a kangashans a skull. not only its a fact that we don’t even know what kind of pokemon the skull belongs to but the head size and shape of a kagashan is completely different.the skull mask that cubone wears snout, is alot long than that of a kangashan who has a shorter snount/rounder head.
also kangashan doesn’t have horns its ears may look it ,but there just ears.

wear as on the skull that cubone wears there are two long horns-one on each side of its skull that have flat tops at the very top.this shows that kangashans resemblance greatly differs.just to add,im not confirming this,but if you think about it the skull that cubone wears looks a lot similar to that of Aerodactyl could it be?????moving forward,lastly another reason i disbelieve cubone isn’t a kangashan is the story told within the pokemon games red,blue and yellow that mention how cubones mother was killed by team rocket.(probably by trying to protect the breeding grounds and habitat of other cubone and her young). this story in particular bothers me/ confuses me. how can there be many cubones whos mother was killed by the hands of a human.i can see there being one cubone, that particular cubone who morns its mothers death.its possible that other “cubone aka kangashan” died but not in that same way, all sharing the same story like this, it just doesn’t sit right with me.this would make that one “cubone aka kangashan” stand out. just how ashes treekco keeps a small twig in its mouth and shows guts,weres other treekco are different(just to add.)well,in closing.these are the reasons why i fell the cubone/kangashan theory to be flawed.