The Importance of Evolutionary Theory: Insights and Implications
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“Life's grandeur is reflected in its diversity, which was initially instilled by the Creator into a few or perhaps a single form; as the Earth has revolved under the unwavering law of gravity, countless beautiful and extraordinary forms have evolved from such a simple origin.” — Charles Darwin, On the Origin of Species (1859)
“To all who aspire to a universal ethics.”
This quote serves as the dedication in David Sloan Wilson's This View of Life. I will frequently reference this book throughout this article series, as I consider it one of the most significant works I’ve encountered recently, alongside Sapiens.
What does it mean to establish a global ethics? It involves creating a moral framework that transcends specific nations, regions, or demographics, aiming for inclusivity across the entire planet. How can we begin to conceptualize such a comprehensive morality?
One key insight from This View of Life is that we should ground our understanding in evolutionary theory. So, what exactly is evolutionary theory? We'll delve into that soon.
First, let’s briefly discuss the nature of theories in general.
The Significance of Theories
Wilson emphasizes repeatedly, “the theory determines what we can observe.” Let’s take a moment to unpack this.
What constitutes a theory? There are many definitions out there. For this discussion, I’ll focus specifically on a scientific theory, a more defined philosophical concept, though I believe this reasoning applies broadly to various aspects of life.
Most of the world is beyond our direct experience; we infer its nature based on our observations. Thus, we create heuristics that suggest we understand more about the world than we actually do. This is the fundamental role of scientific theories: they provide models to help us interpret our surroundings and predict future outcomes. But what occurs when a theory is flawed? A historical case from physics illustrates this point.
A Brief Note on Special Relativity: The Importance of Theories
At the close of the 19th century, physicists were notably confident. They had developed a sophisticated set of four equations (Maxwell’s Equations) that explained electricity and magnetism, thermodynamics was progressing well, and gravity had long been understood thanks to Isaac Newton. Physics seemed nearly complete.
Light was perceived as a wave (an electromagnetic wave described by Maxwell’s Equations), and like other waves — whether on a string, in water, or in air — it was assumed that light must travel through a medium. This hypothetical medium, known as the luminiferous aether, was thought to be a static, massless field that filled space, through which celestial bodies moved. Therefore, it was presumed that Earth was traveling through this aether as it orbited the sun.
When moving relative to a wave source, the observed wave speed changes depending on whether one is moving toward or away from the source (the Doppler Effect). Picture swimming in a wave pool, where moving with the waves feels different from swimming against them. The same principle applies to sound waves, such as those from a siren or a passing train.
A precise experiment, the Michelson-Morley experiment, was conducted to measure light's speed in two perpendicular directions. Given that Earth was moving through the aether, one would expect to find differing light speeds in the direction of its orbit versus perpendicular to it.
However, the results showed no difference. The experiment found that light's speed remained constant, regardless of direction or position in Earth's orbit. The inability to detect a difference baffled scientists, who were convinced the outcome would be clear.
As a result, attempts to rationalize the null result through existing theories fell short. Then, in 1905, Albert Einstein introduced Special Relativity, utilizing a novel mathematical framework to redefine space, time, motion, and light. Einstein’s fundamental assumption was that light’s speed is constant, always the same regardless of circumstances. This counterintuitive idea proved accurate, revealing that light requires no medium to travel; the luminiferous aether was a mere figment of imagination.
This example demonstrates a broader principle: if a theory is incorrect, it leads to misinterpretations and missed insights, causing confusion over seemingly unsolvable problems. The history of science, and indeed human history, is filled with such instances.
Evolution: The Valid Theory Based on Truth
Pre-Darwinian explanations of life’s existence and evolution failed because they were fundamentally flawed, lacking alignment with observable evidence. Darwin was the first to articulate what now seems evident: life evolves, and without external influences (like human intervention), this evolution is driven by the survival and reproduction of the "fittest" — a process known as natural selection.
We often hear the phrase, “evolution is just a theory.” While true, the same applies to relativity and gravity. Theories can be incorrect. In science, we adopt those theories that seem most valid, as they align with empirical evidence and can yield predictive insights.
Today, a wealth of evidence supports the idea that evolution serves as the correct framework for understanding biology. Evolution refers to the changes in species over time, observable in both laboratory and natural settings through human guidance.
Mathematically, evolution can be demonstrated through reproductive rates and probabilities, notably illustrated by the case of the black and peppered moths during early industrial England.
Moreover, dogs serve as a tangible example of evolution in our daily lives. They evolved from wolves, but not through natural selection; humans effectively conducted genetic engineering by leveraging natural variability. By replacing the wolves’ natural selective pressures with our own, we transformed wolves into dogs.
In terms of evidence for evolution via natural selection — the driving force in the absence of human influence — there is an abundance, though many prominent evolutionary thinkers (like Richard Dawkins and Edward O. Wilson) do not often focus on justifying these theories.
A notable book that addresses this is Why Evolution Is True, which integrates contemporary findings from genetics, paleontology, geology, molecular biology, and anatomy, affirming the processes first suggested by Darwin. It dispels common misconceptions surrounding evolution and reinforces its status as a scientific fact.
I will refrain from further justifying evolution, except to state that the evidence supporting Darwinian evolution is as compelling as that for the roughly spherical Earth, the heliocentric solar system, relativity, or even quantum mechanics. If evolution seems implausible, just wait until you explore the intricacies of quantum mechanics or relativity.
Darwin's Groundbreaking Insight
The revelations presented by Charles Darwin were as revolutionary as Einstein’s theories of relativity or quantum mechanics, yet their implications have taken time to resonate beyond biology. Darwin's natural selection theory carries profound philosophical consequences and even theoretical backing from fundamental principles of thermodynamics.
Darwin was the first to articulate a critical insight: biological evolution occurs through natural selection, where environmental pressures determine which organisms endure, allowing them to pass their traits to subsequent generations.
Despite lacking knowledge of DNA and Gregor Mendel's foundational work with pea plants — which illustrated genetic inheritance — Darwin transformed humanity’s understanding of the forces shaping biology and, by extension, all human endeavors.
Darwin recognized that his theory had far-reaching applications. He contemplated applying this analytical framework to human psychology, culture, economics, and politics. Unfortunately, he lacked the tools for significant advancement in these areas.
I believe economics should have emulated biology rather than physics, as I’ve discussed elsewhere. Had this occurred, historical developments could have unfolded differently. Progress is being made, albeit slowly, as seen in the work of Robert Frank and others at organizations like the Evolution Institute.
Since Darwin's groundbreaking contributions, evolutionary theory has become the cornerstone of biology — “Nothing in biology makes sense except in the light of evolution,” noted Theodosius Dobzhansky in 1973. With modern analytical tools, evolutionary theory is finally permeating other fields. My aim in this series of articles is to elucidate some of these intersections.
It's been suggested that Charles Darwin is to economics what Albert Einstein is to physics; the world simply hasn’t recognized it yet. I believe this notion extends even further, as Darwin's insights have implications that span all fields of study. Evolutionary theory offers insights with potentially cosmic ramifications, should humanity endure long enough to venture beyond our solar system or if life exists elsewhere. Should we encounter extraterrestrial life, it may be radically distinct from our own, as DNA is likely not the sole method for encoding life’s information. Other forms of life, shaped by different chemistries and energy sources, could exist in our galaxy, all having evolved through natural selection.
In Part 2, I will introduce the foundational concepts of Darwinian evolution and provide examples of evolution in action.