Some! The one at the end seems to be the master god-figure, if I'm not mistaken. Most of the other Pokémon seem to have some sort of origin that involves being created, or having some sort of ancestor that they descended from. Arceus, on the other hand, supposedly came from an egg that was formed out of the chaos that existed before the universe was created - sort of like the Big Bang, if you're familiar with the concept, but instead of the universe resulting from it, a Pokémon was created, and then that Pokémon created everything else.