"I did not come from a monkey!" is a frequent sentiment among creationists. They feel that they have been created "in God's image", and are simply superior to animals in every conceivable way. We have something they lack: a soul. I find it extremely ironic that it is among those less educated that this attitude of supreme pride is most prevalent. Scientists seem to have no problem accepting that we thinking apes (not monkeys, which are a different branch of the primate family). We are, quite simply, animals.
Even among the general more well educated population, there seems to be a prevailing perception that humans are fundamentally and orders of magnitude smarter and different from other primates. There is a memorable quote, I wish I could remember who said it or exactly how it was said. It says that humans and chimpanzees share 97% the same DNA. But in the 3%, you get language, art, music, literature... in short: civilization.
Do we really? I this where it comes from? Is it just genetics that make this seemingly gaping chasm of difference between us and chimps? Is that 3% (or 1% I think is now the more correct understanding), really what makes the difference between an animal and us? And is the difference as big as we conceive it is? Let's disregard the question of the presence or absence of a soul for the moment and instead focus on nature versus nurture.
Consider two pieces of evidence: Feral Children. Intelligence, tool use, and cultural transmission among chimps.
Numerous examples exist of children who were raised isolated from other humans. Some were living alone in the wild. Some were being cared for by other animals. Some were neglected and abused by parents and never taught even to speak. Without the benefit of learning from other humans, these children lacked all culturally transmitted knowledge and behavior. They lacked language. Most did not walk upright, or not exclusively upright. They didn't dress themselves. They behaved like animals, often mimicking the behaviors of the animals they interacted with.
Chimps live in social groups. They have social structures and culturally transmitted learned behaviors. They plan ahead. They make and use a variety of primitive tools. They excel at intelligence tests and there are even areas where they surpass humans. They resemble, to a great degree, what we know of prehistoric anatomically modern humans.
Humans have been physiologically "modern" for tens of thousands of years, possibly as long as 200,000. This means that these past humans, if they had had the benefit of being brought up in modern society, would likely have been not much different from you or I, if at all. We have had the capacity for language, art, culture and such for a very long time, but it took many many generations of transmitting learned behaviors and knowledge and developing new behaviors before we even began to evolve what we now call civilization. The examples of the feral children show us that without standing on the shoulders of our inherited cultural knowledge, we would be primitive and animal like, much like modern chimps and prehistoric modern humans. I hypothesize that if a population of humans were raised as feral children, without being taught any language or other skills, and allowed to simply live "naturally," and breed and exist for generations without any interaction with any "civilized" humans, it would take them many hundreds of generations to begin to approach a level of cultural sophistication beyond what we see in chimps. It would obviously be unethical in the extreme to carry out such an experiment. But as a thought experiment, it is rather intriguing, and would probably make an excellent sci-fi novel.
Conversely, the examples of apes learning sign language and other complex behaviors shows us just how small the gap between humans and our closest relatives is. The fundamental difference between us is, to a large degree, a matter of circumstance. Given the right environmental stimulation and enough generations, perhaps other apes could evolve civilization as well. We already know there were other branches of the human family tree that had made significant advancements along that path, such as the Neanderthals.
If, as I am suggesting, the difference between us and other apes has much more to do with the transmission of accumulated knowledge from generation to generation, than to do with genetics, or the presence of a soul this should bring us to two important realizations. Firstly, we should be proud. We should look with awe on the incredible achievements of humanity that all rest on one fundamental behavior: teaching our children. Secondly, we should be humbled. We should recognize how close we still are to our animal selves. In this lies the promise of evolutionary psychology: by looking at the behaviors of our closest cousins and knowing how we have behaved through history, we can better understand ourselves. Thirdly, we should look forward. Recognizing we are cultural animals, and not divinely created beings. Recognizing we are a young civilization only beginning to understand our own nature, not the end product of evolution. Recognizing that our history, our cultures, values and the conflicts that go with them are not a fundamental part of our nature, but learned behaviors and ideas. We can reinvent ourselves. We can do away with historical shackles. We can accept those aspects of our animal nature that are good, and control those that are harmful. We can shape the future of our species. This is of course, much easier said than done. But it can be done if we do one simple thing: teach our children. Teach them not to cling to past traditions and accepted "wisdom", but to boldly question and seek always the best answers, supported by evidence and reason.