Summary of Our Improbable Universe
Chapter 8: Madonna and Child
The evolution of the energy of the Big Bang into the complex matter of our solar system took more than five billion years. The evolution of that matter into our complex biosphere took another four billion years. The evolution of the biosphere into the ecosphere of mind, that dominates our reality today, took a half billion years. The process began with the first worms that possess a nervous system. Modern worms have several hundred nerve cells that make a total of about five thousand connections to each other. Our nervous system has over a billion neurons with a total of a trillion connections. Despite this huge improvement in mental capacity, an individual human would never be able to create the huge body of knowledge, art, wisdom and individual personality that is humanity today. This sphere of mind is a collective phenomena. It depends on the union of individuals for its existence. Our ability to unity and communicate has its routes in the love between a mother and child that began more than a hundred million years ago.
The evolution of mammals from reptiles began a quarter billion years ago. At first our ancestors crudely regulated their body temperature with the aid of a fin on their backs that was rich in blood vessels. If they wanted to heat up fast, they would turn sideward to the sun to catch its rays. If they needed to cool off, they would face the sun and let the breeze cool their blood. Regulation of body temperature was a key advantage over their cold blooded competitors because it gave them mobility when the rest of the world was dormant. It also provided an environment in which a complex nervous system could work well.
Later on these reptiles evolved the ability to generate body heat by burning excess calories. This produced a host of evolutionary adaptations. The fin disappeared and hair was evolved to conserve heat. The higher rate of metabolic activity forced the evolution of improvements in teeth, digestion, and lungs. The need of babies for large amounts of food drove the evolution of instincts to care for the young. The warm blooded reptile that did not do this were not competitive because their young did not survive as well. In the jargon of evolutionary biology, love had an adaptive advantage.
True mammals are distinguished by the ability of the mother to nurse the young from the mammary gland. This ability evolved early. Its existence is intimately tied to a caring parent child relationship. The bond between mother and child was further enhanced by the evolution of live birth a hundred million years ago. Prior to that time all land animals, including mammals, laid eggs in nests. This inhibited mobility and created a huge vulnerability to predation of the young. These disadvantages were more costly to mammals because they had to make a comparatively large investment of effort in the rearing of off spring. The marsupials, like the kangaroo, develop the ability to retain and nourish the fetus in their womb. It stayed there until the immune reaction of the mother, against the dissimilar fetal cells, required that it migrate to a pouch where it could safely nurse. The placental mammals, like ourselves, evolved a barrier to the immune rejection of the fetus. They were therefore able to retain the fetus in the womb until it was fully developed. When it emerged, hormones and other instinctual mechanisms established a strong mother/child bond of love.
The loving relationship between mother and child quickly evolved beyond nursing and protection. The wisdom of the mother, that was acquired through life experiences, became available to the children through example. Behavior was no longer exclusively based on instinct and personnel experience. Received wisdom, personality traits, and culture became of increasing importance in the total repertoire of behaviors. After a hundred million years of evolution, it assumed a dominant roll for us. Behavior was no longer tied to the slow evolution of genetic being. Learned behaviors could adapt and evolve far better and more rapidly than instinctual behaviors. The third part in the trilogy of life had begun. Evolution now occurs in a new medium. The collectivity of minds of advanced creatures is now where the real action is.