Just to jump into the fray:
Tacit has a keen understanding of evolutionary theory. That said, Ryck has a good point about many things being unknown. There used to be a fad in psychology (behaviorism) that posited that all animal behavior was automaton-like, with no ability to think. That, of course, is pure arrogance on our part. I'm not saying that I agree that animals think about all the consequences of their action, but neither do humans. We all tend to do what is expedient in the interests of survival.
As to the Gaia hypothesis that I referred to in my previous post (i.e., that the earth is similar to a multicellular organism), that was an analogy. On the other hand, our definition of a multicellular organism is constantly evolving. It is now known, for example, that the human body has more bacterial cells than human cells, and we cannot live without these symbionts. They provide digestive enzymes, compete with pathogens (preventing them from establishing themselves) and produce many vitamins. Since this is the case, are we really organisms or small ecosystems? I doubt that humans are unique in this way.
Now, to the question of humans acting responsibly and/or intelligently: I have been on this earth for 67 years and have discovered that my understanding of life is directly dependent upon my experiences, not what I was taught. In my youth, older people tried to tell me about what they had learned but I was unable to understand them. Now, I do. As a famous musician (I forget his name) quipped, "Life can only be understood by looking backward. Unfortunately, we have to live it while looking forward."
Bear in mind that, by the time people get perspective on things, the world is run by younger people who cannot possibly appreciate that experience. In my view, this is one reason why we never seem to learn anything but continue to make the same mistakes. Many older people, of course, never learn and continue their pursuit of money, sex, and power. I also believe that anyone who seeks power should be automatically disqualified from gaining it. Very few want power for altruistic reasons.
