“Biology is the study of complicated things that give the appearance of having been designed for a purpose.”
To say that biological systems are complicated is an understatement.
When I was in college, I had some friends who avoided taking courses in the life sciences because of the complexity of biological systems. On the other hand, I found the complexity alluring. It’s what drew me to biochemistry. I love to immerse myself in the seemingly never-ending intricacies of biomolecular systems and try to make sense of them.
Perhaps nothing exemplifies the daunting complexity of biochemistry more than intermediary metabolism.
Order in the Midst of Biochemical Complexity
I remember a conversation I had years ago with a first-year graduate student who worked in the same lab as me when I was a postdoc at the University of Virginia. He was complaining about all the memorization he had to do for the course he was taking on intermediary metabolism. How else was he going to become conversant with all the different metabolic routes in the cell?
I told him that he was approaching his classwork in the wrong way. Despite the complexity and chemical diversity of the metabolic pathways in the cell, a set of principles exists that dictates the architecture and operation of metabolic routes. I encouraged my lab mate to learn these principles because, once he did, he would be able to use them to write out all of the metabolic routes with minimal memorization.
These principles make sense of the complexity of intermediary metabolism. Are there similar rules that make sense of biological diversity and complexity?
Rules Govern Biological Systems
As it turns out, the insight I offered my lab mate may well have been prescient.
The idea that a simple set of principles—rules, if you will—accounts for the complexity and diversity of biological systems may be more widespread than life scientists fully appreciate. At least it appears this way based on work carried out recently by researchers from Duke University.1 These investigators discovered a simple rule that predicts the behavior of mutually beneficial symbiotic relationships (mutualism) in ecosystems. Mutualistic interactions play an important and dominant role in ecosystem stability.
The Duke University scientists’ accomplishment represents a significant milestone. Lingchong You, one of the study’s authors, points out the difficulty of finding rules that govern all biological systems:
“In a perfect world, you’d be able to follow a simple set of molecular rules to understand how every biological system operated. But, in reality, it’s difficult to establish rules that encompass the immense diversity and complexity of biological systems. Even when we do establish general rules, it’s still challenging to use them to explain and quantify various physical properties.”2
Yet, You and his collaborators have done just that for mutualism. Their insight moves biology closer to physics and chemistry where simple rules can account for the physical world. Their work holds the potential to open up new vistas in the life sciences that can lead to a deeper, more fundamental understanding of biological systems.
In fact, the researchers think that simple rules dictating the operation of biological systems may not be an unusual feature of mutualistic interactions but may apply more broadly. They write, “Beyond establishing another simple rule . . . we also demonstrated that one can purposefully seek an appropriate abstraction level where a simple unifying rule emerges over system diversity.”3
If the Duke University scientists’ insight generally applies to biological systems, it has interesting theological implications. If biological systems do, indeed, conform to a simple set of rules, it becomes more reasonable to think that a Creator played a role in the origin, history, and design of life.
I’ll explain how in a moment, but first let’s take a look at some details of the Duke University investigators’ work.
Mutualism and Ecosystem Stability
Biological organisms often form symbiotic relationships. When these relationships benefit all of the organisms involved, it is called mutualism. These mutualistic relationships are vital to ecosystems and they directly and indirectly benefit humanity. For example, coral reefs depend on mutualistic interactions between coral and algae. In turn, reefs provide habitats for a diverse ensemble of organisms that support human life and flourishing.
Unfortunately, mutualistic systems can collapse when one or more of the partners experiences stress or disappears from the ecosystem. A disruption in a relationship can lead to the loss of other members of the ecosystem, thereby altering the ecosystem’s composition and opening up niches for invading organisms. Sadly, this type of collapse is happening in coral reefs around the world today.
Mutualism Can Be Explained by a Simple Rule
To gain insight into the rules that dictate ecosystem stability and predict collapse (due to a loss of mutualistic relationships), the Duke University researchers sought to develop a framework that would allow them to determine the outcome of mutualistic interactions. For the predictive framework, the scientists wrote 52 mathematical equations, each one specifically describing one of the various forms of mutualism. These equations were based on a simple biological logic; namely, mutualism consists of two or more populations of organisms that produce a benefit (B) for all the organisms that reduces the stress (S) they experience at a cost (C).
Mathematical analysis of these equations allowed the researchers to discover a simple inequality that governs the transition from coexistence to collapse. As it turns out, mutualistic interactions remain stable when B > S, and they collapse when this inequality is not observed. Though intuitive, it is still remarkable that this simple relationship dictates the behavior of all types of mutualism.
The researchers learned that determining the value of S is relatively straightforward. On the other hand, quantifying B proves to be a challenge due to the large number of variables such as temperature, nutrient availability, genetic variation, etc., that influence mutualistic interactions. To work around this problem, the researchers developed a machine-learning algorithm that could calculate B using the input of a large number of variables.
This work has obvious importance for ecologists as ecosystems all over the planet face collapse. Beyond that, it has important theological implications when we recognize that a simple mathematical equation governs the behavior of mutualistic relationships among organisms.
Let me explain.
The Case for a Creator
From my vantage point, one of the most intriguing aspects of our universe is its intelligibility and our capacity as human beings to make sense of the world around us—quite often, through the use of simple rules we have discovered. Along these lines, it is even more remarkable that the universe and its phenomena can be described using mathematical relationships, which reflects an underlying rationale to the universe itself.
For most of the history of science, the discovery and exploration of the mathematical nature of the universe has been confined to physics and, to a lesser extent, chemistry. Because of the complexity and diversity of biological systems, many people working in the life sciences have questioned if simple mathematical rules exist in biology and could ever be discovered.
But the discovery of a simple rule that predicts the behavior of mutualistic relationships in ecosystems suggests that mathematical relationships do describe and govern biological phenomena. And, as the researchers point out, their discovery may turn out to be the rule rather than the exception.
From my perspective, a universe governed by mathematical relationships suggests that a deep, underlying rationale undergirds nature, which is precisely what I would expect if a Mind was behind the universe. To put it differently, if a Creator was responsible for the universe, as a Christian, I would expect that mathematical relationships would define the universe’s structure and function. In like manner, if the origin and design of living systems originated from a Creator, it would make sense that biological systems would possess an underlying mathematical structure as well—though it might be hard for us to discern these relationships because of the systems’ complexity.
Figure: The Mathematical Universe. Image credit: Shutterstock.
The mathematical structure of the universe—and maybe even of biology—makes the world around us intelligible. And intelligibility is precisely what we would expect if the universe and everything in it were the products of a Creator—one who desired to make himself known to us through the creation (Romans 1:20). It is also what we would expect if human beings were made in God’s image (as Scripture describes), with the capacity to discern God’s handiwork in the world around us.
A Case against Materialism
But what if humans—including our minds—were cobbled together by evolutionary processes? Why would we expect human beings to be capable of making sense of the world around us? For that matter, why would we expect the universe—including the biological realm—to adhere to mathematical relationships?
In other words, the mathematical undergirding of nature fits better in a theistic conception of reality than one rooted in materialism. And toward that end, the discovery by the Duke University investigators points to God’s role in the origin and design of life.
Is There a Biological Anthropic Principle?
As the Duke University scientists show, the discovery of a simple mathematical relationship describing the behavior of mutualistic interactions in ecosystems suggests that these types of relationships may be more commonplace than most life scientists thought or imagined. (See Biochemical Anthropic Principle in the Resources section.)
This discovery also suggests that a cornerstone feature of ecosystems—mutualistic relationships—is not the haphazard product of evolutionary history. Instead, scientists observe a process fundamentally dictated and constrained by the laws of nature as revealed in the simple mathematical rule that describes the behavior of these systems. We can infer that mutualism within ecosystems may not be the outworking of chance events—the consequence of a historically contingent evolutionary process. Rather, these relationships appear to be fundamentally prescribed by the design of the universe. In other words, mutualism in ecosystems is inevitable in a universe like ours.
For me, it is eerie to think that mutualism, which appears to be specified by the laws of nature, is precisely what is needed to maintain stable ecosystems. The universe appears to be structured in a just-right way so that stable ecosystems result. If the universe was any other way, then mutualism wouldn’t exist nor would ecosystems.
One way to interpret this “coincidence” is to view it as evidence that our universe has been designed for a purpose. And purpose must come from a Mind—namely, God.
The Argument from Math and Beauty
Designed for Discovery
The Biochemical Anthropic Principle
The Design of Intermediary Metabolism