Philosophers, theologians and atheists have come up with countless arguments they claim prove or disprove the existence of God(s).
For many, it's a black-and-white issues - YES there is a God, or NO, there is no God. But philosophers have explored many angles (e.g. How does one define "God"?).
I just recently listened to a talk by Alan Watts, who commented on intelligence. I don't know how respected Watts is in the philosophical community. I think he was kind of a 60's pop icon; many of the things he said certainly resonated with me.
Anyway, Watts says it's in the nature of apple trees to produce apples, even using the word apple as a verb (apple trees apple). Similarly, he says it's Earth's nature to "people," producing people the way a fruit tree produces fruit.
Although he didn't go into any detail in this particular talk, he said the rocks from which life evolved are "intelligent."
Though it might sound like a stupid idea, it makes some sense (to me, at least).
Are you familiar with the term Gaia, the view of Earth as a living organism?
If you study evolution, you have to be in awe of some of the amazing trends that have continually transformed Earth. If we could travel back in time to the Cambrian Period, we probably couldn't survive on what was essentially an alien planet. Would there even be enough oxygen in the air to breathe?
Yet the evolution of plants modified the atmosphere itself, at the same time stabilizing the land and nurturing the evolution of soils and herbivorous terrestrial creatures. Predators evolved greater intelligence, and their prey similarly became more intelligent in a sort of biological arms race. Some scientists have described plants as intelligent.
For me, this is powerful evidence that one doesn't need a god in order to create intelligence - unless one believes that a prime mover (e.g. "God") was needed to create the cosmos out of a void, setting everything in motion. Others argue that the cosmos itself is God - a god very different from the Christian god.