Gamefreak never cared for consistency ow world building. Most often there's contradictions between the dex entries and the game mechanics, or one dex entry and another dex entry, or a dex entry and basic common sense, like:
>Kangaskhan is hatched in adult form with the baby in its pouch
>Every single cubone has a dead mother
>Magneton is 10 times heavier than magnemite even though it's just three magnemite

Post as many instances of this as you can, just for the fun of it.