Where does the additional mass come from when a Pokémon evolves? Do they somehow create matter in some bizarre magical process? Is is shunted from another unknown dimension into ours? This isn't evolution, this is spitting on Newton's grave.

The picture is my example. Flareon weighs around 40 pounds more than Eevee. If an Eevee evolved into a Flareon on an unstable surface, wouldn't it just collapse right through it?