First of all, we're not brothers. I didn't come from a monkey, I was created by God. Setting that issue aside, let me address some of your 'finer' points....
But my reasons are flawed. And science tells us that it is because our brains evolved to be smart enough to be curious that our intelligent minds came up with God. And this is funny to me because back then our intelligence is what made us come up with God but today I consider anyone who believes in God to be stupid. Also funny is that there are very intelligent people who believe.
So you figure we are SO intelligent that we had to create an imaginary placebo to console our fears of death and the unknown? As you say, this is "funny" in fact, it makes no rational sense whatsoever. Furthermore, that we (being as intelligent as we are) have mysteriously clung to this false belief for our entire existence in spite of knowledge and science.
If these theories of man creating spiritual beliefs to console fears of mortality were true, we'd expect to see evidence in nature of the same thing happening with other species of life. Higher primates like chimps and great apes, would likely be mimicking some semblance of spirituality, trying to grapple with their mortality. Perhaps not to the degree of forming actual "religions" but at least performing ritual ceremonies and customs... we simply see no signs of this. It doesn't seem to be a big nagging and troublesome problem for other species to accept they are mortal.
Rational thought says the reason man has these "fears of mortality" is because they are spiritually aware of something immortal. It is our spiritual connection which causes this fear, not the other way around. There are literally hundreds of thousands of ways humans have invented to comprehend and understand this intrinsic spiritual connection we have. This is the source of all religion. It is not because we "had to invent something" it's because we are intrinsically aware of something.
Likewise, the meme of "man created religion to explain the unexplained" is also without rational basis. Man created SCIENCE to explain the unexplained. He created religion to explain his intrinsic awareness of something greater than self, his spiritual connection.
The validity of a claim, such as the existence of god, is not governed by the intelligence of the minds which hold it. Evidence and reason are the deciding factors.
Precisely, but the "evidence" shows that humans have always had this intrinsic connection to something beyond the physical. Reason tells us there must be a purpose for this. If there were, in fact, nothing to it and it's all in our heads, man would have abandoned it long ago like they have superstitions and mythological beliefs. Science has been around for centuries, explaining away all the great mysteries, but human spirituality has continued to flourish. Even through periods of brutal reprisal and persecution where millions of people have been killed in the name of their spiritual beliefs. It's something that simply cannot be stomped out of the hearts and minds of mankind, no matter how hard it is tried. We remain highly spiritual creatures with 90% of the species still believing in something greater than self. Even the most devout Darwinist would have to conclude there is a fundamental reason for the attribute to exist in humans.