Students ask: “Do similar structures provide evidence for evolution?”

Does the fact that cars, airplanes, and scooters all have wheels imply that they all evolved from a common ancestor? No! Do similarities shared by different creatures support the teaching that they all descended from a common ancestor? According to science textbooks used in 7th and 10th grade in California, yes!1,2

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Evolutionary textbooks use the term homology to refer to similarities between creatures that are a result of common ancestry.1,2 Common “examples” of homology include the forearm bones in vertebrates (animals with a backbone). Textbooks often point to these kinds of similarities as evidence for evolution, but what does the evidence really show?

Evidence cited for “molecules-to-man” evolution like common structures and patterns are classified as circumstantialevidence, because they must be interpreted through a person’s worldview. Worldviews are made up of a person’s presuppositions—ideas that one has already accepted as true before examining the evidence.

Depending on a person’s presuppositions (i.e., whether or not he accepts evolution), circumstantial evidences can be used to support a wide variety of models. As a result, similarities claimed to be evolutionary “homologies’ can also be used as evidence for a  common purpose or design by the Common Designer, the Creator Jesus Christ. How then do we determine which model is correct? We must test the predictions of each.

The evolutionary model predicted that if similar features (i.e., vertebrate forelimbs) are a result of evolutionary development from a common ancestor, then “homologous” structures should be coded for by similar genes and develop similarly in a wide variety of creatures. However, the creation model, which interprets similarities as a result of common design, predicts that there will be a large genetic and developmental gap between animals belonging to different created “kinds.” What does the evidence show?

Instead of “homologous” structures being coded by homologous genes, genetic evidence shows that similar structures are often coded for by different genes.3 Likewise, similar structures often develop differently in creatures that are supposed to be closely related. For example, frog fingers and the fingers of other amphibians develop in opposite directions, in defiance to the predictions of evolutionary biologists.4

While all creatures on earth share some amount of DNA similarity to one another, the similarities do not confirm the predictions of evolutionary biologists.5 For example, elephant sharks appear to share many genes in common with mammals, but not with their supposedly closer fish relatives!6

The evidence overwhelmingly supports that large genetic gaps exist between creatures, confirming the Genesis account of creation, rather than Darwin’s evolutionary tree.

Free Resources for Further Reading:

Homology Made Simple

Does ‘Homology’ Prove Evolution?

Comparative Similarities: Homology

Darwin vs. Genetics: Surprises and Snags in the Science of Common Ancestry 


1Coolidge-Stoltz, Elizabeth. “Unit 5: Evolution.” Focus on California Life Science. Boston, MA: Pearson Prentice Hall, 2008. 471. Print.

2Miller, Kenneth R., and Joseph S. Levine. Miller & Levine Biology. Boston, MA: Pearson, 2006. 468. Print.

3Bergman, Jerry. “Does Homology Provide Evidence of Evolutionary Naturalism?” Journal of Creation 15.1 (2001): 26-33.Does Homology Provide Evidence of Evolutionary Naturalism? Web. 03 Feb. 2015. <>.

4Wells, Jonathan. Icons of Evolution: Science or Myth?: Why Much of What We Teach about Evolution Is Wrong.Washington, DC: Regnery Pub., 2000. 66-67. Print.

5Morris, Henry M., John D. Morris, Jason Lisle, James J.S. Johnson, Nathaniel Jeanson, Randy Guliuzza, Jeffrey Tomkins, Jake Hebert, Frank Sherwin, and Brian Thomas. Creation Basics & Beyond: An In-Depth Look at Science, Origins, and Evolution. Dallas, TX: Institute for Creation Research, 2013. 138. Print.

6Jeffrey Tomkins, Ph.D. 2014. Shark Genes Devour EvolutionActs & Facts. 43 (8).