Whether I speak at a church, a university, a seminary, or a research firm, during the Q&A time I am inevitably asked about the Cambrian explosion. I also get emails about the Cambrian explosion. Here is an an example from our inbox and my answer:

Q: Have evolutionists come up with any valid explanation for the sudden appearance of the Cambrian explosion? 

A: The Cambrian explosion refers to the sudden, simultaneous appearance of most of the animal phyla (body plans) that occurred 542–543 million years ago. Ten of the many challenges the Cambrian explosion poses to evolutionary explanations for life are as follows:

  1. While evolutionary scenarios, as opposed to worked-out theories, exist for hypothesizing how new genera, new orders, and new families of animal life might appear, there is no rational evolutionary scenario for explaining how a new animal phylum might appear.
  2. From 50–80 percent of the animal phyla known to have existed at any time in Earth’s history appeared within no more than a few million years of one another, as the Cambrian geological era began.
  3. Of the 182 animal skeletal designs theoretically permitted by the laws of physics, 146 appear in the Cambrian explosion fossils.
  4. The Cambrian explosion marks the first appearance of animals with skeletons, bilateral symmetry, appendages, brains, eyes, and digestive tracts that include mouths and anuses.
  5. Virtually every eye design that has ever existed appears simultaneously in the Cambrian explosion.
  6. The moment oxygen levels in Earth’s atmosphere and oceans permit the existence of Cambrian animals, they suddenly appear.
  7. The Cambrian explosion occurs simultaneously with the drastic change in sea chemistry known as the Great Unconformity.
  8. The Cambrian explosion includes the most advanced of the animal phyla, chordates, including vertebrate chordates.
  9. Both bottom dwellers and open ocean swimmers appear simultaneously in the Cambrian explosion.
  10. Optimization of the ecological relationships among the Cambrian animals, including predator-prey relationships, occurred without any measurable delay.

These challenges and several more are documented and described in some depth in chapter 13 of my new book, Improbable Planet (releasing September 2016).

The world’s leading experts on the Cambrian explosion are aware of just how profound and intractable these challenges are to any conceivable evolutionary explanation for the Cambrian explosion. Here are a few of their in-context quotes from their research papers:

“No single environmental or biological explanation for the Cambrian explosion satisfactorily explains the apparent sudden appearance of much of the diversity of bilaterian animal life.”1

—Jeffrey Levinton (marine ecologist, evolutionary biologist)

“The Cambrian ‘explosion’ of body plans is perhaps the single most striking feature of the metazoan fossil record. The rapidity with which phyla and classes appeared during the early Paleozoic coupled with much lower rates of appearance for higher taxa since, poses an outstanding problem for macroevolution.”2

—Gregory Wray (evolutionary biologist)

“Elucidating the materialistic basis of the Cambrian explosion has become more elusive, not less, the more we know about the event itself.”3

—Kevin Peterson, et al. (evolutionary biologists)

You will find more such quotes in chapter 13 of Improbable Planet. To be clear, I am not saying you will not find evolutionary biologists who claim to have an evolutionary explanation for the Cambrian explosion. I have met several. However, those that claim to have an explanation deny the suddenness of the event and the rapidity of its occurrence relative to the physical and chemical events that first make the existence of these animals possible. Typically, they assert that the Cambrian animals appeared in gradually more advanced forms over the course of 40–50 million years. Those evolutionary biologists who are aware of the data establishing the challenges listed above acknowledge that the challenges defy all macroevolutionary models.

Evolutionary biologists who do recognize the failure of evolutionary models to explain the Cambrian explosion often counter those of us who are evangelical Christian research scientists by asking us why God would choose to create Cambrian animals at the time and place that he did. The answer that I document and describe at some length in Improbable Planet is that unless God created the Cambrian animals in the greatest possible diversity at the greatest possible abundance levels at the earliest time permitted by the laws of physics and the history of the universe, human beings and human civilization would be impossible. God’s desire to create a home for human beings where humans could launch and sustain civilization explains why the Cambrian explosion looks the way it does.


  1. Jeffrey S. Levinton, “The Cambrian Explosion: How Do We Use the Evidence?” BioScience 58 (October 2008): 855.
  2. Gregory A. Wray, “Rates of Evolution in Developmental Processes,” American Zoologist 32 (February 1992): 131.
  3. Kevin J. Peterson, Michael R. Dietrich, and Mark A. McPeek, “MicroRNAs and Metazoan Macroevolution: Insights into Canalization, Complexity, and the Cambrian Explosion,” BioEssays 31 (July 2009): 737.


Subjects: Animals, Evolution, Genesis, Naturalism

Check out more from Reasons to Believe @Reasons.org

About The Author

Dr. Hugh Ross

Reasons to Believe emerged from my passion to research, develop, and proclaim the most powerful new reasons to believe in Christ as Creator, Lord, and Savior and to use those new reasons to reach people for Christ. I also am eager to equip Christians to engage, rather than withdraw from or attack, educated non-Christians. One of the approaches I’ve developed, with the help of my RTB colleagues, is a biblical creation model that is testable, falsifiable, and predictive. I enjoy constructively integrating all 66 books of the Bible with all the science disciplines as a way to discover and apply deeper truths. 1 Peter 3:15–16 sets my ministry goal, "Always be prepared to give an answer to everyone who asks you to give the reason for the hope that you have. But do this with gentleness and respect, keeping a clear conscience." Hugh Ross launched his career at age seven when he went to the library to find out why stars are hot. Physics and astronomy captured his curiosity and never let go. At age seventeen he became the youngest person ever to serve as director of observations for Vancouver's Royal Astronomical Society. With the help of a provincial scholarship and a National Research Council (NRC) of Canada fellowship, he completed his undergraduate degree in physics (University of British Columbia) and graduate degrees in astronomy (University of Toronto). The NRC also sent him to the United States for postdoctoral studies. At Caltech he researched quasi-stellar objects, or "quasars," some of the most distant and ancient objects in the universe. Not all of Hugh's discoveries involved astrophysics. Prompted by curiosity, he studied the world’s religions and "holy books" and found only one book that proved scientifically and historically accurate: the Bible. Hugh started at religious "ground zero" and through scientific and historical reality-testing became convinced that the Bible is truly the Word of God! When he went on to describe for others his journey to faith in Jesus Christ, he was surprised to discover how many people believed or disbelieved without checking the evidence. Hugh's unshakable confidence that God's revelations in Scripture and nature do not, will not, and cannot contradict became his unique message. Wholeheartedly encouraged by family and friends, communicating that message as broadly and clearly as possible became his mission. Thus, in 1986, he founded science-faith think tank Reasons to Believe (RTB). He and his colleagues at RTB keep tabs on the frontiers of research to share with scientists and nonscientists alike the thrilling news of what's being discovered and how it connects with biblical theology. In this realm, he has written many books, including: The Fingerprint of God, The Creator and the Cosmos, Beyond the Cosmos, A Matter of Days, Creation as Science, Why the Universe Is the Way It Is, and More Than a Theory. Between writing books and articles, recording podcasts, and taking interviews, Hugh travels the world challenging students and faculty, churches and professional groups, to consider what they believe and why. He presents a persuasive case for Christianity without applying pressure. Because he treats people's questions and comments with respect, he is in great demand as a speaker and as a talk-radio and television guest. Having grown up amid the splendor of Canada's mountains, wildlife, and waterways, Hugh loves the outdoors. Hiking, trail running, and photography are among his favorite recreational pursuits - in addition to stargazing. Hugh lives in Southern California with his wife, Kathy, and two sons.

Email Sign-up

Sign up for the TWR360 Newsletter

Access updates, news, Biblical teaching and inspirational messages from powerful Christian voices.

Thank you for signing up to receive updates from TWR360.

Required information missing