I'm not sure apes kill each other as much as you seem to think. A great ape will rarely kill a member of its own species. And a gorilla, unlike man, will have to be physically driven away and kept away before leaving his family.

But regardless, monkeys and apes have no need of morals. They have instincts. They kill each other over territory as a means of increasing their chances for perpetuating their species, a biological function of nature. Not for greed. Humans do this as well, except we are intelligent enough to know that we could all live together and help each other, while still perpetuating our own species. That is why there is nothing immoral about apes or monkeys killing each other when needed, it's completely natural. Humans on the other hand also kill each other for greed, hate (often religious based hate), and fun, which are certainly what we would call immoral.

That isn't to say humans lack morals completely. But our morals are also a biological function that existed prior to any recorded religious beliefs. Prior to religion, primitive humans did not just run around killing and stealing. These things were done, but again, as a means to control more resources to survive. When tribes needed to increase their resources due to their tribe growing, they would conquer other tribes. But they would almost never kill a member of the same tribe. Most humans do not want to kill another human. And most feel bad when they hurt another human. This is a part of our biology that is there as a way to help us preserve our species as well.

Man is not an intelligent being. He is an instinctive being, with intelligence. We are driven by our instincts, just like primitive man. Only now we have the intelligence to control our behavior. As that intelligence grew, man began developing more intricate communications, and creating structure and answers to the unknown through stories that became religions. Then those beliefs were expanded on as man became more civilized to include what we always considered "good" behaviors. I would actually say that our natural instincts about hurting each other are the primary source of our most commonly shared religious morals. Not the other way around. Humans get a natural aversion to killing other humans for lots of reasons.

Now, of course in situations like the military, or psychopaths, there are exceptions. When someone believes they are killing in the name of doing the greater good, they can overcome their natural instinct to resist killing. Likewise, biologically, your instinctive mind doesn't know that there are 7 billion people in the world, So if you kill one, it really doesn't matter. It just knows that you are killing another human, and so edging the species closer to extinction, hence the natural feeling of hesistation. Unless, as I stated earlier, you have a mental disorder that keeps you from feeling natural reactions that most humans feel when they do bad things.

Also, believing that you understand the fundamental nature of the universe does not mean you do. I can just as easily say that anyone who believes a deity created the universe and has some purpose for it, is an idiot who doesn't understand the fundamental nature of the universe. An atheist doesn't believe in nothing. They lack the belief that some imaginary being created humans and the universe for a purpose that somehow makes humans more special than anything else in the universe. To me that is just an arrogant and idiotic belief. It doesn't mean that an atheist can't believe in anything because they don't believe in a god of some sort. I equate our knowledge of the universe, to the earth sciences knowledge of primitive man. We don't understand it, so we make up something to make us feel better about being so ignorant.

Sorry, I didn't get a notice you had responded to this...

As I already stated, it does happen. But there is nothing immoral about these killings. The gorillas do this instinctively as a biological function to carry on their bloodline and to assure their genes pass from generation to generation. Likewise with competing over females and ranges. While a human has the capacity to understand these instincts and control them, a gorilla does not. I'm not saying gorillas have no intelligence, but it is enough of a gap that they still act according to instinct, and not reason.

As for sources, they would be varied, and based on what I write you can research if you'd like. But I will try to explain my thoughts on this as best I can, which is really all I can do.

4 million years ago when man first walked erect, we were tribal animals. The only way for man to survive was through tribal cooperation. This, coupled with the fact that man was scarce at this time, lends itself to the conclusion that these people were not killing their own tribe members off. It would lesson their chances to survive predators for one, since we were bi-pedal, so we couldn't outrun or out-climb predators. Man at this time did not hunt, they ran. And second, it would have lessened their numbers such that they may have risked extinction. This goes against every instinctive bone in our bodies, even to today.

During this time, man developed his social drives and instincts. Such instincts as mother-love, compassion, cooperation, curiosity, inventiveness and competitiveness are ancient and embedded in the human. They were all necessary for the survival of the human and pre-human. As these are instincts, they cannot be changed through education. Intellect allows us to train ourselves to overcome instinct, but the instinct itself cannot be changed. One of these instincts, was cooperation for survival. As I said, it would go against our own instincts to kill each other off at this time because of predators and the drive to survive. Likewise, we lacked the intellectual capacity to overcome these instincts. So at this point, man did not kill man simply as a survival mechanism.

This is about how it stayed for roughly 2 million years, until man's brain had grown some and we started getting more intelligent. Then along the next million and a half years or so, man changed a lot. Until at a point, man started creating civilizations. Sumer is often considered the earliest known civilization. It existed around 4000BCE. So we are talking from 2 million years ago, until 6000 years ago, there were no civilizations (that we know of). Now let's take some of the earliest religious evidence. Sumerian religion is obviously pretty old, Sumerian Cuneiform with religious records date back to 3000BCE. Hinduism is probably the oldest religion since Krishna is written about to have lived on Earth from 3228 - 3102 in Sanskrit from the time. However, animism has roots going back 60,000 years to Australian Aboriginal people. Although animism is a part of various religions, it is not considered in itself an organized religion. Animism encompasses the beliefs that there is no separation between the spiritual and physical (or material) world, and souls or spirits exist, not only in humans, but also in all other animals, plants, rocks, natural phenomena such as thunder, geographic features such as mountains or rivers, or other entities of the natural environment. (from Wiki) As such, it incorporates no moral code or recognized universal organization.

So, my point in all of this is to show, that between 2 million years ago, and up to roughly 60,000 years ago (being liberal counting animism as a religion), there is no evidence that man incorporated any religious moral code in his life. He lived off of instinct, and it wasn't until he started developing intelligence that let him overcome this instinct, that he even started to create organized religious beliefs that included a moral code. This is why I believe it is reasonable that when man was developing a moral code, he incorporated our already instinctive social behaviors developed over a few million years into it. It is only when man developed the intelligence to overcome his instinct, that he needed morals. So he created laws which incorporated these already existing behaviors into a now intelligent society, able to ignore them.

I thought that is what I was implying when I said:

I really don't disagree with anything you said above. And I completely agree with this being a great discussion!