In all terrestrial organisms, information is transmitted between generations by means of the genetic code; and genetic evolution takes place through natural selection acting on modifications of this code. In human cultural evolution, information is also transmitted between generations by means of language and writing. This second mode of evolution gave our species enormous adaptive advantages. While genetic changes are random and slow, cultural changes are purposeful and rapid. For example, when our ancestors moved out of Africa and spread over Europe and Asia, they did not adapt to the colder climate by growing long fur, but instead invented clothing.
Anachronistic human emotions
Our emotions have an extremely long evolutionary history. Both lust and rage are emotions that we share with many animals. However, with the rapid advance of human cultural evolution, our ancestors began to live together in progressively larger groups, and in these new societies, our inherited emotional nature was often inappropriate. What once was a survival trait became a sin which needed to be suppressed by morality and law.
After the invention of agriculture, roughly 10,000 years ago, humans began to live in societies which were sometimes multi-ethnic. In order to make towns, cities and finally nations function without excessive injustice and violence, both ethical and legal systems were needed.
The very long childhood of humans allows learned behavior to overwrite instinctive behavior.
Humans are capable of tribalistic inter-group atrocities such as genocides and wars, but they also have a genius for cooperation. Cultural evolution implies inter-group exchange of ideas and techniques. It is a cooperative enterprise in which all humans participate. It is cultural evolution that has given our special dominance. But cultural evolution depends on overwriting destructive tribalism with the principles of law, ethics, politeness and kindness. The success of human cultural evolution demonstrates that this is possible. Ethics can overwrite tribalism!
It is no accident that the great historical pioneers of ethics lived at a time when the agricultural revolution had made it possible for humans to abandon their hunter-gather lifestyle and to live in settled communities. Neolithic villages appeared in Europe, India, Egypt, China, and Mesoamerica. As agricultural civilization progresses, the political units that had to be held together by ethics and laws became still larger - cities, and then nations. Our early hunter gatherer ancestors had long practiced fierce inter-tribal warfare as they competed for territory on the grasslands of Africa. However, after the Neolithic agricultural revolution, the settlement of multi-ethnic communities required new ethics to overwrite our anachronistic tribal emotions and behavior patterns. Thus we see the appearance of great social philosophers and religious leaders who developed ethical principles at precisely the time when they were needed.
Science and technology have changed our world
During the initial stages of human cultural evolution, the rate of change was slow enough for genetic adaptation to keep pace. The co-evolution of speech, tool use, and an enlarged brain in hominids took place over a period of several million years, and there was ample time for cultural evolution and genetic adaptation to follow each other. The prolonged childhood that characterizes our species, and the behavior patterns of familial and tribal solidarity, were built into the genomes of our ancestors during the era of slow change, when cultural and genetic evolution moved together in equilibrium. However, as the pace of cultural information accumulation quickened, genetic change could no longer keep up.
Genetically we are almost identical with our Neolithic ancestors; but their world has been replaced by a world of quantum theory, relativity, supercomputers, antibiotics, genetic engineering and space telescopes - unfortunately also a world of nuclear weapons and nerve-gas. Because of the slowness of genetic evolution in comparison to the rapid and constantly-accelerating rate of cultural change, our bodies and emotions are not adapted to our new way of life. They still reflect the way of life of our hunter-gatherer ancestors. Luckily, education in ethical principles is able to overwrite our anachronistic emotions and behavior patterns.
Today we live in a society where global communication is instantaneous, and where countries throughout the world interact economically. We need a global ethical system to match our technologically advanced global society. A society that is technologically advanced, but ethically primitive, will destroy itself. To avert the twin threats of catastrophic climate change and an all-destroying nuclear war, our economic system must be given both an ecological conscience and a social conscience. We must construct a system of international law and governance that is appropriate for a united world. And finally, we need an ethical system in which loyalty to our own family and nation is broadened into loyalty to the large human family that includes all nations and all ethnic groups.
On our small but beautiful Earth - made small by technology, made beautiful by nature - there is room for one group only: the family of humankind.