History of biology with unsubstantiated tributes to evolution
A review of Some Assembly Required: Decoding four billion years of life, from ancient fossils to DNA by Neil Shubin
Oneworld Publications, 2021
Neil Shubin is a well-known evolutionary biologist from the University of Chicago and Provost of the Field Museum of Natural History. He is most well-known for his discovery of Tiktaalik roseae, one of the supposed evolutionary intermediates between fish and land creatures (figure 1). In Some Assembly Required, Shubin takes his readers down memory lane to celebrate some of the most exciting scientific discoveries in paleontology and genetics. The book is essentially a collection of short stories that span the history of genetics. Shubin writes in an engaging narrative style that is informative, yet accessible to the layperson. Readers with a background in molecular biology or genetics will already be familiar with most of the things mentioned here.
The book excels whenever it sticks to history, but falters whenever it tries to extrapolate the scientific discoveries as if they are all proof of evolution. Knowledgeable creationists will agree with many of the scientific discoveries mentioned in the book yet recognize that these do not support evolutionary theory. More concerning, however, is that many of his arguments for evolution are outdated and already refuted in the literature.
Neil Shubin starts the book with a retelling of his call to fame. He talks about his graduate days and the eventual discovery of Tiktaalik (figure 2). Shubin appeals to homology. He explains how the same genes involved in swim bladders in fish are also involved in the development of lungs. Likewise, he appeals to homology in the fins and tetrapod limbs as evidence that fins evolved into limbs. However, creationists have often pointed out that creatures such as mudskippers and lungfish require a whole host of specialized anatomy for them to adapt to life on land—lungs alone are insufficient. Thus, mudskippers and lungfish exhibit the hallmarks of a well-designed creation, not evolution.1 Homology is also best explained as evidence for a common designer.
Both creationists and evolutionists agree that swim bladders and lungs develop from the same basic tissue. In evolutionary terms, this is viewed as evidence for common ancestry. On the other hand, creationists see this as evidence for a common designer using variations of the same basic Bauplan (body plan) to create different creatures. It is no surprise that the same basic archetypal structures would require the same genes. But if the evidence is consistent with both creationary and evolutionary models, how can it be ‘proof’ for evolution?
Joachim Vetter, in his review of Shubin’s earlier books, points out that many ‘higher’ bony fish (the teleosts) and electric fish have lungs: “Lungs appear to be much more ‘ancient’ than swim-bladders, so by this reasoning, lungs must have evolved into swim-bladders!”2 Vetter goes on to explain:
“… there is evidence that the most ancient (according to evolutionary tenets) placoderm fishes already had functioning lungs, which would mean that all ‘primitive’ jawed fish had them. … In spite of the fact that lungs are not needed for survival (fish being able to cope well with gills) they appear and are prevalent among fishes at least 100 million years [Ma] (on the alleged evolutionary time-scale) before their (imaginary) migration to the land.”
Now, this turns Shubin’s swim-bladder-to-lungs hypothesis on its head, but he doesn’t tell his readers this.
Shubin admits that some of the earliest fish in the fossil record have lungs. He argues that fish had already evolved lungs before Tiktaalik, and all it takes are slight changes in the function of existing organs for sea creatures to become adapted to a terrestrial lifestyle. However, Tiktaalik not only has structures more primitive than its evolutionary predecessors, but four-legged land creatures (tetrapods) had already existed at least 18 Ma in the evolutionary timescale before Tiktaalik—so why should Tiktaalik be considered a transitional tetrapod?3
Shubin never addresses these problems. Instead, he acknowledges that since his discovery of Tiktaalik back in 2004, our knowledge of genetics has advanced greatly. If paleontologists today want to remain relevant, they must keep themselves up to date with the latest technological advances in genomics.
From here, Shubin takes us on a journey from paleontological discoveries of the 19th century to modern-day genetics. He goes from George Mivart’s opposition to Charles Darwin to Thomas Huxley’s controversial claim that Archaeopteryx was an intermediate between reptiles and birds. The book quickly transitions from paleontological discoveries to focus on genomics in more recent years. It is a collection of short historical accounts, all attributed to the advancement of evolutionary biology, regardless of whether or not the discoveries had anything to do with evolution. The same usual ‘evolutionary’ stories found in most evolutionary books are retold here: Hox genes, sonic hedgehog genes, axolotls and salamanders, stickleback fish, neonate chimpanzees, the discovery of DNA, endogenous retrovirus, junk DNA, etc.
There are slight historical inaccuracies throughout the book which the keen reader would pick up. For example, if Shubin were more careful, he would have mentioned that it was actually the embryologist and anatomist Gegenbaur who compared Archaeopteryx to Compsognathus and first proposed that birds evolved from dinosaurs in 1864, four years before Thomas Huxley. Most of these historical details are minor and do not have a major impact on the book.
Most of the genomic discoveries mentioned in the book are neutral in the sense that they neither directly support nor refute evolution. Nevertheless, these are included as one of the many historical accounts covered in the book. Every scientific discovery is attributed to the advancement of evolutionary biology, even if most of the discoveries have little to do with evolution.
These aspects are interesting for those new to the subject. For example, Shubin discusses the axolotl and salamander. The amount of water the salamander grows in affects the level of thyroid hormones that its body produces. Thyroid hormones, in turn, control the metamorphosis of the axolotl. His point is that changes in development can produce coordinated modifications in the entire body. A lack of, or insensitivity to, thyroid hormones can result in the salamander keeping a lot of its larval features into adulthood. In salamanders this may result in the retention of external gills, limbs with fewer fingers and toes, an aquatic tail, and/or the failure to reconfigure their skulls, gills, and circulatory system.
Outdated evolutionary arguments
However, significant problems arise whenever Shubin tries to address arguments associated with evolutionary biology. Many of his claims are unfortunately filled with outdated arguments for evolution.
Shubin speaks of how protein and DNA sequences in both humans and chimpanzees are identical and that genetic similarity matches evolutionary phylogenetic trees very well. While it is a common argument by many evolutionists, this is demonstrably false. The actual evidence flies in the face of evolutionary expectations. Different genes and proteins generate different phylogenetic trees, and “phylogenetic conflict seems to be greatest precisely in genes associated with the appearance of new types of organisms in the history of life.”4
Chimps and humans
Shubin also pushes the (now defunct) argument that chimpanzees and humans are 95–98% similar. Again, this is an outdated argument, and this is only true when comparing parts of the DNA that are already known to be similar. If one compares the whole genome, the similarity is less than 85%, a difference of more than ~450 million base pairs. This is highly problematic for evolution since most evolutionists believe that the last common ancestor between chimpanzees and humans lived around 7–13 Ma ago.
Retroviruses and junk DNA
Shubin repeats the evolutionary argument that 10% of our DNA is made up of ancient viruses, 60% is made up of repeated elements from jumping genes gone wild, and that only 2% is made up of our own genes (p. 217).
He argues that HIV is similar to the activity-regulated cytoskeleton-associated protein (Arc). The Arc protein is associated with memory function. He claims that Arc is only found in land-living animals but not in fish. He believes that 375 Ma ago, a virus infected the common ancestor of all land-living creatures, probably a close relative of Tiktaalik. When this viral Arc gene was inserted into the fish’s genome, it made the Arc protein active in brains. From there, the viral genome became domesticated to produce new functions for our brains (p. 165). Shubin claims that our ability to read, write, and recall memories all came about through this ancient viral infection.
However, Arc proteins are known to also form capsid-like structures in fruit flies. They play a significant role in trans-synaptic mRNA transport. Arc proteins bind to dArc1 mRNA and transport the mRNA from motor neurons to muscles. So, far from being an incidental viral infection, the Arc gene serves an important function as part of a larger complex delivery system. In other words, their presence cannot be explained as a chance insertion in the genome by viruses.5
Assuming that Arc proteins are evidence that viruses have contributed much to the evolution of life on Earth, Shubin asserts that most of our DNA consists of a graveyard of past viral infections and repeats caused by jumping genes gone wild. Mutations in these stretches of DNA allow for the formation of new genetic information for evolution. Again, these are all outdated arguments. For example, it is widely recognized that mutations in the gene coding for Arc proteins are associated with autism and schizophrenia. These are not functionless stretches of DNA. Much of what was previously considered ‘junk’ DNA is now known to be functional, and mutations in these so-called junk regions are often associated with various diseases.6
Neil Shubin writes in an engaging narrative style that takes his readers on a historical tour of paleontological and genetic discoveries. The book is written for the layperson and will serve as a helpful introduction to genomic discoveries in the last few decades. Unfortunately, everything from the discovery of DNA to salamander development to the discovery of CRISPR-Cas9 is described as part of the journey that allows us to understand evolutionary history. Throughout the book, I was looking forward to seeing what new arguments the author has for evolution, half expecting his lynchpin argument to be at the end of the book. However, I came to the end only to realize that there is little that is new in this book. Much of it consists of the same evolutionary themes that other similar evolutionary books have been telling for years, including many outdated arguments. The book comes across as a collection of short stories, struggling to sum it all up at the end. While it reads smoothly, it ends somewhat abruptly. I can’t help but feel that this is far from Shubin’s best work.
The thesis of the book is that paleontologists today must keep up with advances in genomics if they want to remain relevant. Yet Shubin is guilty of using outdated arguments from genetics in his bid to promote evolution. The irony is unfortunately lost on him.
References and notes
- Bell, P., Mudskippers—marvels of the mudflats, Creation 34(2):48–50, April 2012. Return to text.
- Vetter, J., Something fishy about lungs, adapted from the German by Dr Carl Wieland, creation.com/something-fishy-about-lungs. Return to text.
- Curtis, J., What’s so great about Tiktaalik? J. Creation 34(1):110–114, 2020. Return to text.
- Luskin, C., Phylogenetic conflict is common and the ‘hierarchy’ is far from perfect, Evolution News & Science Today, 7 Sep 2021, evolutionnews.org/2021/09/phylogenetic-conflict-is-common-and-the-hierarchy-is-far-from-perfect/. Return to text.
- Terborg, P., ERVs and LINEs—along novel lines of thinking, J. Creation 32(2):8–11, August 2018. Return to text.
- Reinikainen, P., Junk DNA—from science stopper to sickness source, 4 Feb 2020, creation.com/junk-dna-science-stopper. Return to text.