El libro plantea que la teoría de la evolución sigue presentando vacíos que no han sido explicados y propone la física de sistemas complejos (el conjunto tiene propiedades que no poseen ninguno de sus elementos) como posible explicación.
So by the late twentieth century, we have a theory of natural selection which says that mutations arise
spontaneously in genes, that the environment favors the mutations that are beneficial, and out of this selection process evolution occurs. It’s simple and straightforward. God is not at work. No higher organizing principle involved.
Problemas a esa teoría:
1. Escala temporal
there are problems with that idea,” Malcolm said. “First of all, there’s a time problem. A single bacterium—the earliest form of life—has two thousand enzymes. Scientists have estimated how long it would take to randomly assemble those enzymes from a primordial soup. Estimates run from forty billion years to one hundred billion years. But the earth is only four billion years old. So, chance alone seems too slow. Particularly since we know bacteria actually appeared only four hundred million years after the earth began. Life appeared very fast—which is why some scientists have decided life on earth must be of extraterrestrial origin.
2. Evolución coordinada
“Second, there’s the coordination problem. Many things must evolve. Bats need a specialized apparatus to make sounds, they need specialized ears to hear echoes, they need specialized brains to interpret the sounds, and they need specialized bodies to dive and swoop and catch insects. If all these things don’t evolve simultaneously, there’s no advantage.
3. No afecta a todos los organismos por igual
“Next problem. Evolution doesn’t always act like a blind force should. Certain environmental niches don’t get filled. Certain plants don’t get eaten. And certain animals don’t evolve much. Sharks haven’t changed for a hundred and sixty million years. Opossums haven’t changed since dinosaurs became extinct, sixty-five million years ago. The environments for these animals have changed dramatically, but the animals have remained almost the same. Not exactly the same, but almost. In other words, it appears they haven’t responded to their environment.”
Creacionismo por supuesto no es una opción
“Are you saying evolution is directed?” “No,” Malcolm said. “That’s Creationism and it’s wrong. Just plain wrong. But I am saying that natural selection acting on genes is probably not the whole story.
¿Es, por tanto, la física de lo complejo una opción?
we know the sequence of amino acids that make up hemoglobin. But we don’t know how to fold it. Fortunately, we don’t need to know that, because if you make the molecule, it folds all by itself. It organizes itself. And it turns out, again and again, that living things seem to have a self-organizing quality. Proteins fold. Enzymes interact. Cells arrange themselves to form organs and the organs arrange themselves to form a coherent individual. Individuals organize themselves to make a population. And populations organize themselves to make a coherent biosphere. From complexity theory, we’re starting to have a sense of how this self-organization may happen, and what it means. And it implies a major change in how we view evolution.”
Aparte, sobre el desarrollo intelectual del ser humano:
As time went on, our ape ancestors developed more complex tools. That stimulated their brains to grow in size and complexity. It began a spiral: more complex tools provoked more complex brains which provoked more complex tools. And our brains literally exploded, in evolutionary terms. Our brains more than doubled in size in about a million years. And that caused problems for us.” “Like what?” “Like getting born, for one thing. Big brains can’t pass through the birth canal—which means that both mother and child die in childbirth. That’s no good. What’s the evolutionary response? To make human infants born very early in development, when their brains are still small enough to pass through the pelvis. It’s the marsupial solution—most of the growth occurs outside the mother’s body. A human child’s brain doubles during the first year of life. [...] good solution to the problem of birth, but it creates other problems. It means that human children will be helpless long after birth. The infants of many mammals can walk minutes after they’re born. Others walk in a few days, or weeks. But human infants can’t walk for a full year. They can’t feed themselves for even longer. So one price of big brains was that our ancestors had to evolve new, stable social organizations to permit long-term child care, lasting many years. These big-brained, totally helpless children changed society. Being born in an immature state means that human infants have unformed brains. They don’t arrive with a lot of built-in, instinctive behavior. Instinctively, a newborn infant can suck and grasp, but that’s about all. Complex human behavior is not instinctive at all. So human societies had to develop education to train the brains of their children. To teach them how to act. Every human society expends tremendous time and energy teaching its children the right way to behave.
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