Wednesday, October 7, 2015

Cambrian Fossil Mystery

In June 2013 Dr. Stephen C. Meyer’s popular volume Darwin’s Doubt appeared on bookshelves. In their fervor to uphold the proposal that 19th century Darwinian theory had been established as a prominent scientific icon of the day, many contemporary critics of Intelligent Design (ID) attacked Meyer’s treatise as “unscientific.” Believers in common descent evolution are happy to join this popular chorus. Adherents of ID such as Meyer respond that the argument between evolutionists and ID theorists is not a classification discussion concerning what is science and what is non-science. Rather, Meyer appeals that the argument should remain “on point:” The on-point question is, “Are the claims of ID true?”

In any assertion that common descent evolution is true, we search for evidence that a slow progression of life forms from simple to complex has been manifest in the fossil record in a branching pattern. Ideally, the branching tree imagery should be clearly in evidence. The single trunk represents the initial common ancestor. The hypothesized complex multi-branched tree foliage represents today’s millions of species branching away from the common ancestor. However, precursor Pre-Cambrian fossils are not in evidence. Meyer calls this the “mystery of the missing fossils.”

Meyer’s series of interview programs on The John Ankerberg Show in July and August 2015 highlighted the startling evidence for a sudden inception of a large number of phyla never before seen. The sudden event was termed “The Cambrian Explosion.” This explosion of life forms was a geologically sudden appearance of complex structures such as compound eyes, spinal cords, and articulated limbs in a metaphorical blink of an eye. If we represent the entire duration of Earth’s planetary existence on a 24-hour clock, the Cambrian Explosion of new animals occurred at about the 21st hour and lasted only two minutes. A majority of the 36 phyla (major body plans) in existence today appeared quickly in the Cambrian period beginning 530 million years ago. Most of these phyla are still extant today.

Only a few life forms had appeared prior to the Cambrian. Fossils of blue-green algae floated on the oceans very early in Earth history. Sponges (porifera) appeared much later in the Pre-Cambrian, organized into colonies of cells. Other simple life forms existed. Then, a spectacular burst of innovation and diversity in animal forms appeared. The descriptive imagery of an “explosion” is entirely appropriate. It is also as though we awaken to a foggy morning and have it quickly replaced by spectacular sudden clarity with bright sunshine after the fog dissipates.

Darwin’s doubt about evolution originated in his early experience from 1831. Geologist Adam Sedgwick was assisted by Darwin as a young student at Cambridge University before his trips to the South Seas. An apparently dramatic event initially manifest in Cambrian rocks mystified the geologists. Sedgwick and Darwin had become curious about the enigma. Darwin’s mystification persisted until the end of his life but his Origin of Species theory had gripped him and many in the scientific world by that time. Perhaps the startling discoveries of many additional Cambrian fossils in the next century would have turned the tide of Darwin’s thinking. He died in 1882. 

Geologist R. G. McConnell had discovered “stone bugs” in the rocks on the slopes of Mt. Stephen in the Town of Shield, British Columbia in 1886. They were fossilized trilobites! In future explorations of the area a plethora of unique fossils was found in the Burgess Shale. In 1909 Charles Walcott made additional startling discoveries. His studies continued in that area for many years. Cambrian animals are examples of pure innovation in multiple body plans—a study in structural and functional creativity. In the 1970s a young geologist, Simon Conway Morris, began unlocking more secrets of the Burgess Shale fossil treasures; expanded discoveries of fabulous Cambrian animal diversity still continue. Preservation of soft body parts is astonishing.

But these animals are a puzzle, even according to avowed evolutionists such as Richard Dawkins: “It is though they were just planted there, without any evolutionary history.” Advocates of evolution expect to observe a gradually branching “evolutionary tree.” Branching evolutionary trees remain literary icons of evolutionary texts. Instead, an evolutionary “lawn” is in evidence—a sudden appearance of many individual, diverse specimens with little if any evidence of predecessors or transitional forms. This scenario was inscrutable for Charles Darwin. It is still enigmatic for modern evolutionary theorists, but they remain entrenched in optimism that evolution will ultimately be proven. To the present day the theory has not been proven. With time the theory may be headed for refutation instead of proof.

I close with a personal anecdote. In the summer of 2013 the Reasons to Believe organization sponsored a “Burgess Shale Adventure” in the Canadian Rockies. Among other visits to geological sites was a visit to the famous Burgess Shale site on Mt. Stephen in the town of Field, BC. The trip was led by scholars Hugh Ross and Fazale Rana. The 900m ascent on a 9 km, 7 hour hike up Mt. Stephen to the site of this world famous geological treasure proved more than challenging for me personally. The trek is aptly described as “strenuous.” My wife and I made it half way up before turning back. We settled for splitting a slab of trilobite-bearing shale provided by the Mount Burgess Geoscience Foundation guides when the hikers returned. Our memories consist of our personal “We were there” story: We hiked to within a few hundred feet of the Burgess fossil beds—one of the most famous geological sites attesting to divine creativity and intelligent design.