REVIEW: What the Fossils Say and Why It Matters

“Evolution is happening all around us. It happens every time a new germ invades your body, a new pest or weed destroys our crops, or a new insecticide-resistant fly or mosquito bites you. Creationists may get some personal comfort from their beliefs, but they cannot change the fact that life is evolving all around us and threatens our survival if we don’t come to terms with that evolution.” (p. 118)


 

If the most profound truths are destined to be the most polarizing, then Darwin is a heavyweight in the scientific arena. From an empirical vantage point, the passage of time has been exceptionally kind to his ideas, yet this scrupulously supported body of science still denotes very different things to different people. For some, mere mention of the topic conjures up deep-seated animosity, while for others it is an example of the heightened grandeur science can evoke.

One might think something so well-established would not so thoroughly dichotomize public attitude, but this mystery is clarified by unboxing the countermovement’s religious underpinning. Evolution’s conflict with a literal exegesis of Genesis is not an insignificant problem for fundamentalists, who feel roused to stamp out this object of dissonance at every turn. In what has become de rigeur for many of these blocs, scientific perspectives are measured against the canons of church teaching rather than the other way around. Adaptation is selected by committee, not by nature. Combine this with man’s long-harbored fancies about our place in the cosmos and you have an idea ripe for naysaying.

Charles Darwin himself might have identified with such sentiments early in his career. Like many of his contemporaries, he found little reason to doubt the literal truth of the Bible, having been raised in an Anglican family under the Church of England, the state-established Christian institution in Britain circa 19th century. By all tradition and probability, Darwin seemed destined to pursue a life of piety and vicarage, but his gaze was set on loftier pursuits. At the hale and nimble age of twenty-two, Darwin accepted consignment to the HMS Beagle and embarked on the famed Pacific voyage that would forever imprint his thinking and shift his worldview.

His observations during this expedition were difficult to stomach initially. He noticed that animals on outlying oceanic islands like the Galápagos were nothing like those on the nearest mainland, and that the fossils left behind by extinct species shared a stronger resemblance to the local fauna than they did to continental fauna. From these initial whispers was spun a thesis for the ages: life on earth had adapted to the environment in which it found itself, with Nature the arbiter. So conscious was Darwin of the weighty implications of his newfound understanding that he sat on the concept of natural selection (or “descent with modification”, as he preferred to call it) for more than twenty years before taking it public. Even absent the evidence that would best support his theory–the fossil record, which was sparse at the time–and the field that would tie it all together–genetics–Darwin’s observations and insight were groundbreaking.

More than one hundred and fifty years later, his landmark ideas tend to provoke the same animus as in the 1860s. No amount of corroboration seems sufficient to dissipate its detractors; evolution science is still disputed and rejected by the bulk of religious America, in stark contrast with the rest of the developed world according to recent indicators. This is unfortunate, not just because it signals anti-intellectualism, but because biological evolution, our evolution, ranks among the most important discoveries in all of science. Its advent ushered in a far more intricate and, indeed, far less anthropocentric understanding of life over against the unquestioned orthodoxy of distinctly created “kinds.”

While there may always be holdouts who drum up controversy in a bid to undermine the science, there is no such controversy within the scientific community. Evolution: What the Fossils Say and Why It Matters, from reputable paleontologist of 30 years, Donald Prothero, illuminates both sides of this longstanding narrative. With his expertise in fossils and other inter-applicable disciplines, Prothero enlightens his readers on why the occurrence of evolution is part of the furniture of reality and shoots down the biblically motivated dismissals of creationists who deny this reality.

First Things First

Before establishing the positive case for common descent, Prothero first targets the religious engines which fuel its nonacceptance, allocating considerable space to biblical origins and context. I cannot commend this approach enough. All of the evidence in the world is not enough to sway fortified religious mindsets. The ballast of fundamentalism must first be kicked aside.

The forays into biblical interpretation are admirable and strike at the heart of creationism. Entire sections are devoted to precursory creation and flood myths, such as those of the Sumerians and Babylonians, the Documentary Hypothesis, and debunking “flood geology.” As Prothero tells us, “The Bible is a composite of multiple sources that did not always agree with each other.” (p. 30) It is truly refreshing to see a scientist as capable of dissecting the often thorny issues of religion as of science, even though his treatment here is unlikely to break new ground for those well-versed in biblical studies.

All roads lead back to the American creationist movement, and its cognate intelligent design (ID), from its hyper-evangelical roots in the 19th century to the many spouts of obstructionist fervor in the courtroom.1 While most of these efforts collapsed of course, there is a rich history to be told here of the rhapsodic and very much ongoing quarrel over the legality of teaching alternatives to evolution in public school systems around the country. Prothero also recounts his own debates with creationists and the predictable tactics they employ to evade the portfolio of evidence unearthed by the scientific community. With devastating effectiveness, Prothero yanks the rug out from the creationism and ID peddlers and pinpoints the errors in their tattered objections.

Fossils Tell the Story

In reconstructing the evolutionary history of life, scientists look to the strongest clues available: those written in the earth itself. As one of the most accomplished paleontologists of the past two decades, having been on the front lines of discoveries of the highest echelon, Prothero is in rare form with his dizzying knowledge of the fossil record. Unfortunately for biologists, the discovery of a fossil is actually an overwhelmingly improbable event due to the unforgiving processes of fossilization and deposition, combined with the fact that few are actually searching for them. Prothero remarks that it is a miracle the fossil record is complete as it is, walking us through example after example of evolutionary sequences, highlighting transitional forms along the way as well as each taxon’s overall place in the topiary of life.

Our guided tour commences with the smallest of life on earth, the microbial forms of bacteria and viruses which subsist in our shared struggle for survival and the relatively rapid evolution these microfossils undergo. We next work our way up to invertebrates, and from there, fish, and then proceed to the nonamniote tetrapods (what the rest of us might call amphibians). Next Prothero discusses the selection pressures giving rise to land-based animals’ return to the sea and the reptilian’s branching evolutionary tree leading to the dinosaurs and, later, birds. Priority is then shifted to the mammals. Horse, rhino, pinniped (seals, sea lions and walruses) and whale evolution are among the most remarkable examples in science of later observation confirming prediction.2

The book concludes with a recap of our own origins. Some 6,000 hominid fossils have been located to date, and biologists have made significant progress on piecing together the complete canvas of human evolution. The various collections preserved by museums around the world document our ancestry in near-cinematic form. Upon Prothero’s first visit to the Kenya National Museum, he reminisces, “A tour through the bomb-proof hominid vault in the Kenya National Museum in Nairobi is a revelation: a whole room full of fossils that document our evolution, and whose existence the creationists must deny.” (p. 336)

 

Australopithecus sediba skull via Wikimedia Commons

                                   

Slaying the Slain

If there is a knock to be made against the book, it is Prothero’s relentless captivation with creationists, especially Duane Gish, whom Prothero has debated multiple times in public. Early on he focuses on debunking creationist mantra, and this boxing match never seems to let up. In fact certain portions of the book seem almost entirely addressed to a creationist, which wouldn’t be so bad if something new was offered each time denialism was inserted into the discussion, but it felt largely like a repetition of points made earlier.

On a somewhat pickier note, I wished Prothero had mentioned one of the primary objections to fossil science: the reconstruction of a full specimen from a small number of bones. As paleontologists will emphasize, you do not need a complete set of bones to extrapolate with accuracy a full skeleton. For example, the human body is comprised of 206 bones, but many of those are redundant. If the left tibia bone is intact, the right tibia is unnecessary. Once you account for all the duplicate bones, you’re left with 120 unique fragments. Moreover, there are specific bones which serve as defining features for certain genera, relegating other bones to a lower priority. This is important because rarely is a full set found in the wild.

Closing Thoughts

Of all the threads of evidence buttressing evolution, the fossil record represents the most irrefutable testament to life’s evolutionary past, and the variety of testimony on display here reaches a scale and lucidity few others can match. While Prothero marshals independent data from the disciplines of embryology, vestigiality, comparative genomics and biogeography as well, the punch line of the book is the none too shabby fossil record, which only grows more exhaustive each year. After the last page had been turned, I couldn’t help but feel once more a sense of awe at the diversity of life that has roamed this planet and the time-tested principles which account for it. I find endlessly perplexing the fundamentalist’s continued preoccupation with ancient creation stories when life’s evolutionary history is ever more breathtaking, more nuanced and more surreal juxtaposed with the prosaic passages introducing the biblical texts. Prothero lays down an airtight case, premised on a voluminous amount of empirical evidence, for the truth of the former and against the fallaciousness of the latter.

Part textbook, part literary non-fiction, part creationist’s worst nightmare, Evolution: What the Fossils Say and Why It Matters is perhaps the most accessible resource on the topic and presents the most comprehensively compelling case for evolution of any I have read to date. It answered the most questions and, dare I say, qualifies as a fine candidate for the go-to reference for creationist debunking. Highly recommended.


 

Note: This review is mirrored by Goodreads and Amazon.


 

Footnotes:

 

  1. Christian fundamentalist sentiment can be traced even further back to the 18th century, when James Hutton’s theory of uniformitarianism was met with sharp resistance due to its conflict with Noah’s flood. “Flood geology”, as it’s been called, predated Darwinism.

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  2. Mammalian phylogeny is probably the most relatable and intriguing to non-scientists and layman readers, but there is only so much space one can dedicate to the fossil evidence while giving equal due to the rest of animal taxonomy. For those looking for a more in-depth rundown of mammal-specific evolution, I recommend picking up Prothero’s earlier work, Horns, Tusks, and Flippers: The Evolution of Hoofed Mammals.

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