Incredulity alert.
Given that the cosmos has had 14 billion years and is inconceivably vast in extent, I'd pretty much expect that every combination and configuration of matter that were possible would emerge sooner or later, somewhere or other. Any neuroanatomist will further confirm the human brain is a prime exemplar of incremental evolution suggesting stages of development in the past with new areas of cortex being added to deal with novel conditions.
Contrast that with the idea of a creator god, far more complex than any human brain, just existing out of nowhere with no context with no provenance with no derivation, now that is way more implausible than a complexity that emerges slowly over billions of years.
An interesting final argument described I believe as Dawkins finest but this wouldn't be your morning stroll without some kind of challenge, so here we go.
1: Nobody need pose an unevolved God given that God has an eternity as opposed to a measly 14 billion years.
2: We cannot say what constitutes life. I borrowed that from a big hitting antitheist refuting a theist but can't remember the link.
3: It is a firmly materialist argument with all the problematic baggage that entails.
4: The multiverse as suggested by mathematics might negate or modify gradualism.
5: The unreasonable efficacy of mathematics and the maths based universe.
6: The complexity of maths and its independence of physical influence. In other words the same maths is always available now or 14 million years ago.