Book Review by Bob Zannelli
Evolution for Everyone: How Darwin’s Theory Can Change the Way We Think About Our Lives
Occasionally a book comes along that gives us nothing less than a paradigm shift. David Sloan Wilson’s ‘Evolution for Everyone’ may be just such a book. Wilson makes a compelling case that in failing to incorporate evolutionary theory in the social-political sciences – including economics – we have faulty models, which are based on an incorrect view of human nature.
For example, Wilson writes that many anthropologists, holding to the dogma of linear social progression, have declared themselves anti-evolutionists; and in psychology, we have behaviorism, which ignores the evolutionary origins of animal behavior. In economics, we have the rational choice theory, which likewise fails to take into account human social behavior as revealed to us by evolutionary theory.
Wilson asserts that while Darwin’s theory is profound, it is also highly accessible to nonscientists, unlike quantum mechanics and general relativity, the two bedrock theories in the physical sciences.
Of particular interest to Wilson are religion and its relationship to Darwin’s theory. One assertion of Wilson that is sure to jar the social science and philosophic communities is the distinction he makes between “practical realism” and “factual real-ism.” Practical realism is the creation of models of reality that are not factually ac-curate but are adaptive in the promotion of more harmonious social groups. Wilson makes no value judgment on this; he reports it as an observation. He asserts that we need to scientifically study religion based on the social role it plays if we are ever going to be able to deal with its negative effects.
Wilson offers what he calls the four principles of evolutionary theory:
The principle of natural selection
This is the assertion that there is an active selection process at work in nature, a process that lacks any purpose or plan. This process of selection operates by chance variations in individual organisms, which can affect reproductive fitness in a given environment.
While most of these random variations decrease the organism’s reproductive fitness, some variations result in the organism becoming more adaptive to its environment. These variations will be preserved via the process of inherited traits, the ability to pass on genetic information to offspring.
Not all successful adaptations are what we would view as good.
Some adaptations are destructive at a larger or longer timescale. For example, cancer is an adaptation of a cell, which greatly in-creases its reproductive success in the short-term. But because of the long-term effect of this adaptation, it decreases the overall long-term fitness of the cancerous cells. The emergence of intelligence may also fall into this category if we are not able to effectively cope with the problems created by our greater ability to effect changes in our own environment.
Inherited traits are complex.
Inherited traits are linked in complex ways due to the structure of the genome. This creates traits that have no reproductive success implications but merely persist because they are linked in the genome with traits that do contribute to reproductive success.
Evolution is a slow process.
The process of evolution is often too slow to react to relatively rapid environmental changes. Because of this, we see periodic extinctions at times of significant environmental upsets. But even for smaller environmental changes, we can often observe what Wilson calls dancing with ghosts – behaviors that are no longer adaptive but persist anyway. The emergence of intelligence is an adaptation that allows organisms to better modify behavior in response to environmental variations, but even here, the adaptive benefits of intelligence are limited.
In the long battle between the advocates of some form of group selection process and those who insist that only individual selection is at work in evolution, Wilson comes down strongly on the side of group selection.
Wilson writes, “It’s groups all the way down,” starting from the simplest organisms. Citing the work of Lynn Margulis, he points out there is evidence that the basic cells, which make up multicellular life (eukaryotes) are them-selves evolved from communities of simpler bacteria cells (prokaryotes). Working even further down the evolutionary ladder, we find that bacteria are social groups of genes, and genes might be considered social groups of DNA strands. From the most basic units of life up to complex societies, the basic story of evolution is the formation of evermore extended group structures. Wilson asserts that while it’s true that the degree of individualism of the constituent parts that make up a given group is greater as the scale of groups increases, group selection is nevertheless a central feature of evolution.
But as Wilson also relates, it’s not all goodness and light. On every scale of group structure, there is a tension for individuals with regard to reproductive success in pursuing a cheating behavior or in pursuing a more altruistic behavioral strategy. This is clearly illustrated by an interesting organism named Dictyostelium discoideum or “Dicty” for short. As an individual, this organism is a solitary ameba but at times when greater mobility is needed to reach food sources, individual amebas collect and form a slime mold, creating a larger organism in which the amebas assume specialized roles. In this “community” of individuals, one can observe all the complexity of any group, from cheating individuals to self-sacrificing altruism.
Wilson believes that this improved and enlarged understanding of the evolutionary process is a corrective to the erroneous ideas usually attributed to Herbert Spencer. In the last few chapters, Wilson applies his views of the evolutionary process to the situation in which humankind finds itself in the 21st century. He asserts we are not fated for violence by our genes. Our bloody past need not foretell our future. Our evolutionary history is not just about ruthless competition, though this is certainly a big part of the story, but also about the emergence of altruism and cooperative behavior starting with the earliest and most primitive forms of life. Given the central role evolution plays in forming our nature – together with Wilson’s fairly radical departure from earlier understandings of the evolutionary process – it seems fair to say that Wilson has written an important book for Humanists to contemplate.