Do humans have intrinsic value apart from God?

If we look at the world from an atheist point of view, humans are nothing more than highly evolved animals. It is impossible to say that humans have special intrinsic value apart from the fact that we are made in the image of God. We do have unique DNA, but so does a cockroach. We may be the most intelligent, but what if we find an animal that is more intelligent than a person with a mental disability? Would that make the animal more valuable than that human? We all FEEL that we as humans have intrinsic value, but from an atheistic perspective there is simply no reason to think that humans have any value greater than our animal "relatives". The only way we can have intrinsic value is if we were made in the image of God as the Bible suggests.