eh, their pretty straight forward with mewtwo is mew's clone.
i like the "cubone is a baby kangiskhan" idea.
supposedly kangiskhan was originally supposed to be the evolved of marowak. and that they scraped this idea and rather than delete marowaks evolution data simply moved it to an unused buffer. this buffer is occupied by random unused data known as missingno. supposedly this is why missingno evolves into kangiskhan, cuz it has marowak's old data.
some supporting things i've noticed;
giovanni uses ground type pokemon, except for kangiskhan. almost as if it was supposed to be a ground type.(like marowak)
pokemon gold/silver may be referencing this link by putting cubone, marowak, and kangiskhan all in the same area.

thoughts on this theory?