Evolutionists argue that anatomical, physiological, biochemical, and genetic similarities among species (homologies) are best explained by evolution. They don’t think God would have employed such similarities if he had created everything (which, as I noted previously, is a theological and metaphysical argument evolutionists make, not a scientific one). But perhaps there’s another explanation. Perhaps biological similarities can be explained by common design instead of common descent.

We could argue, biophysicist Cornelius Hunter writes, that “the Creator used the patterns found in homologous structures so that scientists could more easily analyze his creations and figure out how biology works.” Consider that such similarities allow for us to learn about biological life. What’s true for one organism might be applicable to others. Universality permits discoverability. Biochemist Fazale Rana explains:

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.

Without such similarities among organisms, we wouldn’t be readily able to learn about the biological realm. Scientific discovery would be considerably more tedious. But instead, biological similarities aid us in making progress in scientific discoveries and developments in areas like medicine, conservation, and biotechnology.

This concept of common design isn’t new. Nineteenth-century biologist and anatomist Sir Richard Owen argued that biological similarities among species reflect a common template or archetype God used to create life on Earth. He found it incredible that a single template, like the pentadactyl structure of vertebrate limbs, could have such a range of functions.

Bioengineer Stuart Burgess, who has studied the vertebrate limb structure in depth, agrees. He argues:

The great versatility of the vertebrate limb pattern challenges the limb homology argument that the skeletal layouts of the whale flipper and bird wing are not what would be expected for those applications and make sense only when seen to be a consequence of evolutionary inheritance…. The vertebrate limb pattern is so versatile that it is actually highly optimal not just for arms and legs but also for flippers and wings.

Burgess further states that the pentadactyl structure has “great potential for the bioinspired design of robotic and prosthetic limbs.” That is, it’s even inspiring human technological developments.

In other words, the basic pattern of the vertebrate limb is not only versatile but exquisitely well-designed; it’s able to produce various motions and functions in diverse environments. This is in contrast to the evolutionists’ perspective that a single archetype would be limiting with regard to both the various species’ abilities (since it’s the same basic design instead of distinctive structures uniquely suited to each species’ environment and activities) and also God’s creative abilities (since God could have used endless designs rather than just a single one).

Along these lines, Rana concludes:

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.