行動の適応と進化　宇宙に進出した人類は？

抄録

Human nature is a product of human brain activity, and human brain is an organ which functions to assess environmental information and to make decision about what to do next. Many aspects of human nature must be the results of evolution through natural selection in which favorable genes were selected under the environmental stress. Now, we live in civilized societies based on highly developed technology, using computers, contemplating about the relativity theory, mastering the calculus etc. However, this was not an environment where our basic human nature evolved. That environment was the one which surrounded our ancestors. Humans lived as hunter-gatherers in most of the time during evolution, and the human brain evolved to solve those problems confronted at those times. The resulting decision-making algorithms were so flexible that we can now deal with novel problems of our time using the same old decision-making algorithm. The evolution of behavior is a very complex process and no one gene is controlling any particular behavior. Genes are indeed involved in producing adaptive behavior but a behavior is produced through many other pathways as well, such as learning. We have evolved a huge brain which is capable of producing culture. Culture is a human creation but at the same time, culture has become our environment to which we have to adapt. Thus gene-culture coevolution has been a very important process in human evolution. After we have acquired language, perhaps we have acquired an almost unlimited cognitive power. Many of our cultural invention is the results of our cognitive activity and these things have become parts of our environment. However, cognition is only a small part of the workings of our brain. Human nature is also under control of emotion. Emotional processes are mostly subconscious and have changed little through evolutionary time. In the future, misfits between our cognitive products and emotional process may create many difficult problems which we have never experiences so far.