Because I am a Christian, I see evidence for design in the biological realm. But for me, the converse is also true. Because I see design in the biological realm, I am a Christian. In fact, the elegant designs of biochemical systems convinced me as a graduate student that a Creator must exist and be responsible for life’s origin, paving the way for my conversion to Christianity.
Yet, many skeptics see the features of biological systems very differently than I do. They maintain that life’s origin, design, and diversity are best explained as the outworking of evolutionary processes. As evidence for this view, biologists point to the shared biological and biochemical features (homologies) possessed by organisms that naturally group or cluster together.
Homologous features may perform different functions and superficially appear different, yet they are fundamentally built around the same design. The quintessential example of a biological homology is the vertebrate forelimb—the human hand, the whale’s flipper, a dog’s paw, a bird’s wing, etc. Though these forelimbs are structurally distinct and perform different biological tasks, they are fundamentally built around the same design. The forelimb of every vertebrate consists of a long bone (humerus) in the arm, an elbow, two bones in the forearm (the radius and ulna), wrist bones (carpals), bones in the “hand” (metacarpals), and “fingers” (phalanges).
Image: Homologous structures of the vertebrate forelimb. Image Credit: Wikipedia
Evolutionary biologists interpret homologous structures as evolutionarily derived from ancestral features possessed by the common ancestor of the group. With respect to the vertebrate forelimbs, biologists maintain that the forelimb of the first tetrapods had the same design as all vertebrate forelimbs. However, through the course of evolutionary history, natural selection altered the vertebrate forelimbs to perform a variety of functional roles.
However, as a creationist and a design proponent, I maintain that homologous structures have been designed around an archetypical plan that existed in the Creator’s mind. To put it another way, homologous structures reflect common design, not the outworking of common descent.
My view on shared biological features led my Facebook friend Phil, a skeptic, to ask the following questions:
“Just think about the diverse range of creatures an actual creator could have made. And yet we see creatures appearing like and acting like family cousins instead. What would compel an actual designer with unlimited power to design all creatures with the same template, as if the design was a restriction on the designer? Perhaps it was to make belief more difficult, to make only rebellious (non-credulous) hearts disbelieve?”
Interesting questions, to be certain. This question gets to the core reason why evolutionary biologists reject the arguments for intelligent design. For these many biologists, homologous structures only make sense from within an evolutionary framework.
The View of Biological Homologies before Darwin
Part of the response to my friend Phil’s question can be found in the theoretical work of Sir Richard Owen, a prominent biologist from the UK who predated Darwin. One of the world’s most important anatomists in his day, Owen played a key role in discovering, describing, and interpreting biological homologies. Owen understood homologies from a design perspective. Specifically, Owen saw these mutual features as manifestations of a common blueprint that existed in the Creator’s mind, and, in turn, were physically manifested in the created order.
Archetypes and God’s Creativity
Instead of seeing the concept of the archetype as restricting God’s creativity, Owen regarded the archetype as reflecting teleology of the highest order. In his presentation to the Royal Institution of Great Britain, Owen lectured: “The satisfaction felt by the rightly constituted mind must ever be great in recognizing the fitness of parts for their appropriate functions; but when this fitness is gained as in the great toe of the foot of man or the ostrich, by a structure which at the same time betokens harmonious concord with a common type, the prescient operations of the One Cause of all organization becomes strikingly manifested to our limited intelligence.”1
In other words, Owen marveled at the way the Creator generated so much functional diversity from a single template—for example, the pentadactyl architecture of the vertebrate forelimb.
In fact, the diversity of life on Earth today—even throughout life’s history—built from 30 or so body plans (corresponding to the known animal phyla) is nothing short of mind-boggling. So, apparently creating life on Earth around design templates has done little to limit the Creator. In fact, I would argue—as Owen did— it highlights God’s ingenuity.
Designed for Discovery
There are a few reasons why God would have created life’s diversity using a limited set of templates. But, perhaps the most important reason is discoverability.
The universal nature of biochemistry and the homologous and convergent biological systems allow scientists to generalize what they learn studying one organism to the entirety of the biological realm, in some instances. The universal and homologous designs in biology allow the scientific community to make use of organisms as model systems. For example: by studying DNA replication in bacteria, we have gained key insight that allows us to understand DNA replication in all life on the planet. Studying gene regulation in yeast helps us understand gene regulation in human beings. Studying the developmental pathways of the nematode C. elegans has yielded important knowledge that helps us understand growth and development in many multicellular organisms. Studying genetics in the fruit fly Drosophila has provided key understanding regarding inheritance.
If, as my friend Phil wants, the Creator used a near infinite array of biological designs when he created, it would be virtually impossible for us to know anything about the living realm. The process of discovery in biology would become cumbersome and laborious.
Because the living realm is intelligible, it is possible for human beings to take advantage of God’s provision for us, made available within the creation. As we study and develop an understanding of the living realm, we can deploy that knowledge to benefit humanity—in fact, all life on Earth—through agriculture, medicine, conservation efforts, and emerging biotechnologies.
Ultimately, I believe that God has designed the biological realm for discoverability because He wants us to see, understand, and appreciate his handiwork as a Creator, so through his creation we can know him.
“It is the glory of God to conceal a matter; to search out a matter is the glory of kings.”