There has been plenty of proof. See my other comments. There has not been any proof that they don't exist. If you're making a positive claim you need to add sou

There has been plenty of proof. See my other comments. There has not been any proof that they don't exist. If you're making a positive claim you need to add sources. Otherwise you're getting into a celestial teapot argument. "Can't disprove it so it has to be true."