Without a doubt, humans, chimpanzees, and other organisms share similar features. An early explanation was that these features reflect similar designs because they serve similar purposes. Then evolutionary theory hypothesized that similar features were explained by (and are evidence for) descent from a common ancestor. Which explanation matches the evidence?

Case Study: Common Design vs. Common Ancestry

The history of the debate between whether common design or common ancestry better explains biological similarity is a fascinating case study. It starts at a time before researchers could identify the order of DNA’s building blocks and deals with what each side expected to find when technology became more advanced—either that the building blocks would be similar (common design) or dissimilar (common ancestor).

This is a head-to-head match between the design-based intuitions of creationists and the predictions of the foremost evolutionary theorist, Ernst Mayr. This case study tests the quality of each theory by evaluating the accuracy of its predictions and also shows the value of having an accurate theory so that researchers can think correctly and be on the right track from the outset.

We’ll trace the development of thought by some creationists and intelligent design (ID) advocates from early design-based intuitions to a historical science. This enabled inferences based on design detection and finally led to the bona fide, hypothesis-based theory of biological design (TOBD). ICR is developing the TOBD into a fully operational theory that helps craft detailed research questions and enables specific predictions.¹ Finally, we’ll see how evolutionary predictions made to explain similar features proved instead to be major blunders.

Design-Based Predictions: Common Central Design—Unique Details

As early as 1802, William Paley, a pioneer of design-based explanations, compared living things to human-engineered machines. He postulated that the origins of similar features in diverse creatures could be explained by how man-made machines are copied and uniquely modified for similar—but not identical—uses. He wrote,

Whenever we find a general plan pursued, yet with such variations in it as are, in each case, required by the particular exigency for the subject…we possess, in such a plan and such adaptation…the strongest evidence for intelligence and design….Arkwright’s mill was invented for spinning cotton. We see…such modification of the original principle, such variety of the same plan…to observe it in different applications [for spinning wool, flax, and hemp]….Very much of this reasoning is applicable to what has been called comparative anatomy. In their general economy, in the outlines of the plan, in the construction as well as offices of their principal parts…²

Paley held that similar comparative anatomy was due to similar functions by design. It wasn’t until the mid-twentieth century that links between anatomy and genetic information were better understood. So the different explanations for similarity naturally extended past anatomy to genetics.

In 1975, Dr. Henry Morris claimed there would be common underlying design patterns to explain similar structures. He wrote,

The creative process would have designed similar structures for similar functions and different structures for different functions….In the creation model, the same similarities are predicted on the basis of a common purposive designer.³

The “creative [or engineering design] process” referenced includes a minimum of (1) recognizing the purpose of a design, (2) identifying its constraints, and (3) producing the needed underlying information (specifications, spatial layout and orientation, schedule, etc.) for construction.

This set the stage decades in advance for techniques that could conduct detailed genetic analysis and allow for a rare head-to-head test of ID and evolutionary expectations. While the differing traits of various organisms let them occupy diverse environmental niches, advocates for design-based explanations still expect that similar features fulfilling similar purposes are based on similar information. Extreme multistep, specified regulation over thousands of details produces organisms that are unique but still have similar overall plans.

Evolutionary Predictions: Not Similar Information but Convergent Evolution

All prominent evolutionists reject the common design predictions, but their rationales differ. Darwin’s was theological, doubting “that it has pleased the Creator to construct all the animals and plants in each great class on a uniform plan.”⁴ He derided any hypothesis that claimed similar anatomy and information reflect common design as “not a scientific explanation.”⁴

Ernst Mayr, Harvard’s leading evolutionary theorist, predicted in 1963 that looking for similar DNA between very diverse organisms would be pointless. He explained differences in creatures’ traits by random genetic changes over millions of years that obliterated genetic similarities.

Much that has been learned about gene physiology makes it evident that the search for homologous genes [similar codes due to common ancestry] is quite futile except in very close relatives. If there is only one efficient solution for a certain functional demand, very different gene complexes will come up with the same solution, no matter how different the pathway by which it is achieved. The saying “Many roads lead to Rome” is as true in evolution as in daily affairs.⁵

Since common ancestry does not explain similarities in organisms whose ancestors “diverged” eons ago, new evolutionary explanations have emerged. Now “convergent evolution” is frequently invoked, as denoted in Mayr’s “Many roads lead to Rome” pronouncement.

For example, what explains similar parts found in diverse creatures’ eyes? Evolutionists claim similar environments “pressured” the creatures to independently converge upon comparable complex features at least 40 times, and probably as many as 65.⁶ This evolutionary naturalistic explanation counterintuitively posits that millions of years of genetic tinkering propels organisms to diverge into increasingly different classes while simultaneously cobbling their traits to converge upon “the same solution” to problems.⁵

Creationists remain skeptical that highly complex structures independently evolve over and over again. They also characterize the evolutionist’s imagined convergent evolution as a mystical rescuing device to explain biological observations that are contrary to the belief in universal common ancestry.⁷

Evolutionary Predictions Were Spectacularly Wrong

A landmark discovery between 1978 and 1984 identified a common genetic basis prescribing how similar structures can be built across diverse organisms.⁸ One example is Hox genes, whose regulatory and developmental functions are responsible for core basic design patterns in developing embryos.

This astounding find was so opposite evolutionists’ notions that it clearly constituted a spectacular evolutionary blunder. Evolutionary biologist Sean Carroll described the implications of the discovery.

When the sequence of these homeoboxes were examined in detail, the similarities among species were astounding. Over the 60 amino acids of the homeodomain, some mice and frog proteins were identical to the fly sequences at up to 59 out of 60 positions. Such sequence similarity was just stunning. The evolutionary lines that led to flies and mice diverged more than 500 million years ago….No biologist had even the foggiest notion that such similarities could exist between genes of such different animals. The Hox genes were so important that their sequences had been preserved throughout this enormous span of animal evolution.⁹

He continued,

The discovery that the same sets of genes control the formation and pattern of body regions and body parts with similar functions (but very different designs) in insects, vertebrates, and other animals has forced a complete rethinking of animal history, the origins of structures, and the nature of diversity. Comparative and evolutionary biologists had long assumed that different groups of animals, separated by vast amounts of evolutionary time, were constructed and had evolved by entirely different means.¹⁰

Yet evolutionists still won’t consider that these genes may have a common designer. Rather than concede their predictions were greatly mistaken, they’re just “stunned” at the appearance of this supposedly new, unexpected evidence for evolution. The only evidence that Hox genes can be “preserved throughout this enormous span of animal evolution” is the belief that life evolved from a common ancestor.⁹

And what about all of those “sure” claims of convergence? They get promptly but quietly scrapped. Voilà, Hox genes instantly turn into preserved ancient DNA, which is now used—with equivalent certainty—as evidence of common ancestry.

Creationist Expectations of Common Design and Information Confirmed

It is now factually confirmed that similar genetic regulatory information is common to many classes of organisms and aids in achieving similar functional anatomy—many with remarkably similar designs. Sean Carroll again relates the confounding weight of this finding.

It was inescapable. Clusters of Hox genes shaped the development of animals as different as flies and mice, and now we know that includes just about every animal in the kingdom, including humans and elephants. Not even the most ardent advocate of fruit fly research predicted the universal distribution and importance of Hox genes. The implications were stunning. Disparate animals were built using not just the same kinds of tools, but indeed, the very same genes!¹¹

What about the teaching that 40 independent evolutionary events developed eyes? That proved to be another incredible evolutionary blunder and validation of creationists’ design-based expectations. As Carroll candidly continues,

Natural selection has not forged many eyes completely from scratch; there is a common genetic ingredient to making each eye type, as well as to the many types of appendages, hearts, etc.¹²

Hox genes appear to be the “smoking gun” of common design that creationists expected for decades. Eyes as sensors are the common design, and Hox genes are the common information across diverse groups of organisms. In other areas of research, this fact would be ascribed to common engineering instructions.

TOBD Predictions Are More Precise

Dr. Morris’ correct expectations came simply from design-based intuitions. ICR’s theory of biological design is even more useful. It assumes that basic research of biological functions is within the domain of engineering practice and that these functions will be accurately characterized by engineering principles.

A TOBD extends Paley’s 1802 principle that corresponding similar features between different creatures is due to similar function to predict that we will find corresponding elements between human-engineered and biological systems performing similar functions. Thus, analyzing human engineering practices can inform biological predictions.

Scientific predictions will be more precise, and likely more accurate, if science adopts the operational theory of biological design that hypothesizes that the best explanation for why creatures appear so highly engineered is that they are engineered. And the glory will belong to the Master Designer, our Creator Jesus Christ.

References

1. Guliuzza, R. J. 2024. Why Biology Needs a Theory of Biological Design, Parts 1, 2, 3, and 4; Guliuzza, R. J. 2024. Applying the Theory of Biological Design to Optimal Owl Flight. Acts & Facts. 53 (2–6), various pages.
2. Paley, W. 1802. Natural Theology: Or, Evidences of the Existence and Attributes of the Deity, Collected from the Appearances of Nature, 2nd ed. London, England: R. Faulder, 227–258.
3. Morris, H. 1975. The Troubled Waters of Evolution. San Diego, CA: Creation-Life Publishers, 84–85.
4. Darwin, C. 1872. On the Origin of Species By Means of Natural Selection, 6th ed. London, UK: John Murray, 383.
5. Mayr, E. 1963. Animal Species and Evolution. Cambridge, MA: Harvard University Press, 609.
6. Land, M. and R. Fernald. 1992. The Evolution of Eyes. Annual Review Neuroscience. 15: 1–2. Referencing Salvini-Plawen, L. and E. Mayr. 1977. On the Evolution of Photoreceptors and Eyes. Evolutionary Biology. 10: 207–253.
7. Guliuzza, R. J. 2017. Major Evolutionary Blunders: Convergent Evolution Is a Seductive Intellectual Swindle. Acts & Facts. 46 (3): 17–19.
8. Lewis, E. 1978. A Gene Complex Controlling Segmentation in Drosophila. Nature. 276: 565– 570; Wakimoto, B. and T. C. Kaufman. 1981. Analysis of Larval Segmentation in Lethal Genotypes Associated with the Antennapedia Gene Complex in Drosophila melanogaster. Developmental Biology. 81 (1): 51–64; Scott, M. and A. Weiner. 1984. Structural Relationships Among Genes That Control Development: Sequence Homology Between the Antennapedia, Ultrabithorax, and Fushi tarazu Loci of Drosophila. Proceedings of the National Academy of Sciences. 81 (13): 4115–4119; Slack, J. 1984. A Rosetta Stone for Pattern Formation in Animals? Nature. 310: 364–365.
9. Carroll, S. 2005. Endless Forms Most Beautiful. New York: W. W. Norton & Company, 64.
10. Ibid, 71.
11. Ibid, 65.
12. Ibid, 72.

This article is adapted from Guliuzza, R. J. 2015. Major Evolutionary Blunders: Evolutionary Predictions Fail the Reality Test. Acts & Facts. 44 (9): 17–19.

Dr. Guliuzza is the president of the Institute for Creation Research. He earned his doctor of medicine from the University of Minnesota, his master of public health from Harvard University, and received an honorary doctor of divinity from Southern California Seminary. He served in the U.S. Air Force as 28th Bomb Wing flight surgeon and chief of aerospace medicine. Dr. Guliuzza is also a registered professional engineer and holds a B.A. in theology from Moody Bible Institute.