If you could visit a theme park that offered you a chance to view and even interact with real-life dinosaurs, would you go? I think I might. Who wants to swim with dolphins when you can hang out with dinosaurs? Maybe even ride one?

Well, if legendary paleontologist Jack Horner has his way, we just might get our wish—and, it could be much sooner than any of us realize. Horner is a champion of the scientific proposal to resurrect dinosaurs from extinction. And it looks like this idea might have a real chance at success.

Horner’s not taking the “Jurassic Park/World” approach of trying to clone dinosaurs from ancient DNA (which won’t work for myriad technical reasons). He wants to transform birds into dinosaur-like creatures by experimentally manipulating their developmental processes in a laboratory setting.

The Evolutionary Connection between Birds and Dinosaurs

The basis for Horner’s idea rises out of the evolutionary paradigm. Most paleontologists think that birds and dinosaurs share an evolutionary history. These scientists argue that shared anatomical features (a key phrase we’ll return to) between birds and certain dinosaur taxa demonstrate their evolutionary connection. Currently, paleontologists place dinosaurs into two major groups: avian and nonavian dinosaurs. Accordingly, paleontologists think that birds are the evolutionary descendants of dinosaurs.

So, if Horner and others are successful, what does this mean for creation? For evolution?

Reverse Evolution

In effect, Horner and other interested scientists seek to reverse what they view as the evolutionary process, converting birds into an evolutionarily ancestral state. Dubbed reverse evolution, this approach will likely become an important facet of paleontology in the future. Evolutionary biologists believe that they can gain understanding of how biological transformations took place during life’s history by experimentally reverting organisms to their ancestral state. Reverse evolution experiments fuse insights from paleontology with those from developmental biology, molecular biology, comparative embryology, and genomics. Many life scientists are excited, because, for the first time, researchers can address questions in evolutionary biology using an experimental strategy.

Proof-of-Principle Studies

The first bird that researchers hope to reverse-evolve into a dinosaur-like creature is the chicken (Gallus gallus). This makes sense. We know a whole lot about chicken biology, and life scientists can leverage this understanding to precisely manipulate the embryonic progression of chicks so that they develop into dinosaur-like creatures.

As I described previously (see Resources for Further Exploration), in 2015 researchers from Harvard and Yale Universities moved the scientific community one step closer to creating a “chickenosaurus” by manipulating chickens in ovo to develop snout-like structures, instead of beaks, just like dinosaurs.¹

Now, two additional proof-of-principle studies demonstrate the feasibility of creating a chickenosaurus. Both studies were carried out by a research team from the Universidad de Chile.

In one study, the research team coaxed chicken embryos to develop a dinosaur-like foot structure, instead of the foot structure characteristic of birds.² A bird’s foot has a perching digit that points in the backward direction, in opposition to the other toes. The perching digit allows birds to grasp. In contrast, the corresponding toe in dinosaurs is nonopposable, pointing forward.

Figure 1: Dinosaur Foot Structure. Image credit: Shutterstock

Figure 2: Bird Foot Structure. Image credit: Shutterstock

The researchers took advantage of the fact that vertebrate skeletons are plastic, meaning that their structure can be altered by muscle activity. These types of skeletal alterations most commonly occur during embryonic and juvenile stages of growth and development.

Investigators discovered that muscle activity causes the perching toe of birds to reorient during embryonic development from originally pointing forward to adopting an opposable orientation. Specifically, the activity of three muscles (flexor hallucis longus, flexor hallucis brevis, and musculus extensor hallucis longus) creates torsion that twists the first metatarsal, forcing the perching digit into the opposable position.

The team demonstrated that by injecting the compound decamethonium bromide into a small opening in the eggshell just before the torsional twisting of the first metatarsal takes place, they could prevent this foot bone from twisting. The compound causes muscle paralysis, which limits the activity of the muscles that cause the torsional stress on the first metatarsal. The net result: the chick developed a dinosaur-like foot structure.

In a second study, this same research team was able to manipulate embryonic development of chicken embryos to form a dinosaur-like leg structure.³ The lower legs of vertebrates consist of two bones: the tibia and the fibula. In most vertebrates, the fibula is shaped like a tube, extending all the way to the ankle. In birds, the fibula is shorter than the tibia and has a spine-like morphology (think chicken drumsticks).

Figure 3: The Lower Leg of a Chicken. Image credit: Shutterstock

Universidad de Chile researchers discovered that the gene encoding the Indian Hedgehog protein becomes active at the distal end of the fibula during embryonic development of the lower leg in chicks, causing the growth of the fibula to cease. They also learned that the event triggering the increased activity of the Indian Hedgehog gene likely relates to the depletion of the Parathyroid Hormone-Related Protein near the distal end of the fibula. This protein plays a role in stimulating bone growth.

The researchers leveraged this insight to experimentally create a chick with dinosaur-like lower legs. Specifically, they injected the amniotic region of the chicken embryo with cyclopamine. This compound inhibits the activity of Indian Hedgehog. They discovered that this injection altered fibula development so that it was the same length as the tibia, contacting the ankle, just like in dinosaurs.

These two recent experiments on foot structure along with the previous one on snout structure represent science at its best. While the experiments reside at the proof-of-principle stage, they still give scientists like Jack Horner reason to think that we just might be able to resurrect dinosaurs from extinction one day. These experiments also raise scientific and theological questions.

Do Studies in Reverse Evolution Support the Evolutionary Paradigm?

On the surface, these studies seemingly make an open-and-shut case for the evolutionary origin of birds. It is impressive that researchers can rewind the tape of life and convert chickens into dinosaur-like creatures.

But deeper reflection points in a different direction.

All three studies highlight the amount of knowledge and insight about the developmental process required to carry out the reverse evolution experiments. The ingenious strategy the researchers employed to alter the developmental trajectory is equally impressive. They had to precisely time the addition of chemical agents at the just-right levels in order to influence muscle activity in the embryo’s foot or gene activity in the chick’s developing lower legs. Recognizing the knowledge, ingenuity, and skill required to alter embryological development in a coherent way that results in a new type of creature forces the question: Is it really reasonable to think that unguided, historically contingent processes could carry out such transformations when small changes in development can have profound effects on an organism’s anatomy?

It seems that the best the evolutionary process could achieve would be the generation of “monsters” with little hope of survival. Why? Because evolutionary mechanisms can only change gene expression patterns in a random, haphazard manner. I would contend that the coherent, precisely coordinated genetic changes needed to generate one biological system from another signals a Creator’s handiwork, not undirected evolutionary mechanisms, as the explanation for life’s history.

Can a Creation Model Approach Explain the Embryological Similarities?

Though the work in reverse evolution seems to fit seamlessly within an evolutionary framework, observations from these studies can be explained from a creation model perspective.

Key to this explanation is the work of Sir Richard Owen, a preeminent biologist who preceded Charles Darwin. In contemporary biology, scientists view shared features possessed by related organisms as evidence of common ancestry. Birds and theropod dinosaurs would be a case in point. But for Owen, shared anatomical features reflected an archetypal design that originated in the Mind of the First Cause. Toward this end, the anatomical features shared by birds and theropods can be understood as reflecting common design, not common descent.

Though few biologists embrace Owen’s ideas today, it is important to note that his ideas were not tried and found wanting. They simply were abandoned in favor of Darwin’s theory, which many biologists preferred because it provided a mechanistic explanation for life’s history and the origin of biological systems. In fact, Darwin owes a debt of gratitude to Owen’s thinking. Darwin coopted the idea of the archetype, but then replaced the canonical blueprint that existed in the Creator’s Mind (per Owen) with a hypothetical common ancestor.

This archetypal approach to biology can account for the results of reverse-evolution studies. Accordingly, the researchers have discovered differences in the developmental program that affect variations in the archetype, yielding differences in modern birds and long-extinct dinosaurs.

The idea of the archetype can extend to embryonic growth and development. One could argue that the Creator appears to have developed a core (or archetypal) developmental algorithm that can be modified to yield disparate body plans. From a creation model standpoint, then, the researchers from Harvard and Yale Universities and the Universidad de Chile didn’t reverse the evolutionary process. They unwittingly reverse-engineered a dinosaur-like developmental algorithm from a bird-like developmental program.

Why Would God Create Using the Same Design Templates?

There may well be several reasons why a Creator would design living systems around a common set of templates. In my estimation, the most significant reason is discoverability.

Shared anatomical and physiological features, as well as shared features of embryological development make it possible to apply what we learn by studying one organism to others. This shared developmental program makes it possible to use our understanding of embryological growth and development to reengineer a bird into a dinosaur-like creature. Discoverability makes it easier to appreciate God’s glory and grandeur, as evinced in biochemical systems by their elegance, sophistication, and ingenuity.

Discoverability also reflects God’s providence and care for humanity. If not for the shared features, it would be nearly impossible for us to learn enough about the living realm for our benefit. Where would biomedical science be without the ability to learn fundamental aspects about our biology by studying model organisms such as chickens? And where would our efforts to re-create dinosaurs be if not for the biological designs they share with birds?

Resources for Further Exploration

Reverse Evolution

• “The Creation-Evolution Controversy in ‘Jurassic World‘” by Fazale Rana (article)

Shared Biological Designs and the Creation Model

• “Archetype or Ancestor? Sir Richard Owen and the Case for Design” by Fazale Rana (article)
• “Why Would an Infinite Creator Employ the Same Designs?” by Fazale Rana (article)
• “Does Old-Earth Creationism Make God Deceptive?” by Fazale Rana (article)
• “Duck-Billed Platypus Venom: Designed for Discovery” by Fazale Rana (article)

Some people attempt to justify their unbelief of Christianity on the grounds that the Bible contains irreconcilable difficulties and contradictions. One important role Christians serve in an apologetics-evangelism context is to try to remove obstacles that people have to believing in the truth of Scripture and thus in the truth of historic Christianity.

I once heard an atheist ask how the Gospel writers could conceivably know the nature of the private conversation between Jesus and Pontius Pilate before his condemnation and crucifixion (e.g., John 18:28–40). After all, the apostles—the proposed authors of the four Gospels—were not privy to this confidential dialogue.

This is a reasonable question. So, how can the Christian respond? There are two explanations to this objection, one purely natural and the other supernatural (or theological), but the two are not mutually exclusive.

First, given the nature of the controversy in Jerusalem surrounding Jesus of Nazareth and his public trial by the Romans (Luke 24:13–24), Pilate may simply have spoken to others about the content of his conversation with Jesus. These verbal details may have been conveyed to other Roman leaders and/or to the Jewish religious leaders and then to the followers of Jesus themselves. Jesus also had secret followers among both the leaders of the Romans (the centurion, Matthew 8:5–13) and the Jews (Nicodemus, John 3:1–15).

Undoubtedly, the apostles were interested in all the details of Jesus’s arrest, trial, and execution. It is not difficult to see how the nature of this conversation may have leaked out, especially to key people involved in the events. Though people today may object that this is “hearsay,” the ancients wouldn’t have shared that objection. They may well have interpreted the conversation as part of the important details conveyed by reliable sources concerning Jesus’s public trial and crucifixion. Furthermore, if the details of this alleged conversation were factually wrong, hostile critics who may also have been knowledgeable about the exact nature of the conversation could have falsified them (serving as a type of unofficial cross-examination).

Second, the content of this private conversation between Jesus and Pilate may have come to the writers of the Gospels through the process of divine inspiration. In the Gospel of John, chapters 14–16, Jesus informed the apostles that the Holy Spirit would come and guide them, inform them, and give them exact recall of the truthful events on Jesus’s life, death, and resurrection. Consider two biblical statements about the Holy Spirit’s role in inspiring the biblical authors:

But the Counselor, the Holy Spirit, whom the Father will send in my name, will teach you all things and will remind you of everything I have said to you.

–John 14:26

But when he, the Spirit of truth, comes, he will guide you into all truth.

–John 16:13

Biblically speaking, divine inspiration could serve to give the apostles new information or to confirm the truth of information drawn from another source. Therefore, from the Christian perspective, both of these explanations could be correct.

So this skeptical objection has a plausible answer and thus doesn’t constitute a viable reason to doubt either the truth of Scripture or the ultimate truth of historic Christianity.

Resources

For the resolution of other common Bible challenges and difficulties, see:

• New International Encyclopedia of Bible Difficulties by Gleason L. Archer Jr.
• The Big Book of Bible Difficulties by Norman L. Geisler and Thomas Howe

I don’t like to think of myself as technology-challenged, but I am beginning to wonder if I just might be. As a case in point, I have no clue about all the things my iPhone can do. It isn’t uncommon for someone (usually much younger than me) to point out features of my iPhone that I didn’t even know existed. (And, of course, there is the TV remote—but that will have to serve as material for another lead.)

The human genome is a lot like my iPhone. The more the scientific community learns about it, the more complex it becomes and the more functionality it displays—functionality about which no one in the scientific community had a clue. It has become commonplace for scientists to discover that features of the human genome—long thought to be useless vestiges of an evolutionary history—actually serve a critical role in the structure and function of the genome.

Long noncoding RNAs (lncRNAs) illustrate this point nicely. This broad category of RNA molecules consists of transcripts (where genetic information is transferred from DNA to messenger RNA) that are over 200 nucleotides in length but are not translated into proteins.

Though numbers vary from source to source, estimates indicate that somewhere between 60 to 90 percent of the human genome is transcribed. Yet only 2 percent of the genome consists of transcripts that are directly used to produce proteins. Of the transcripts that are untranslated, researchers estimate that somewhere between 60,000 to 120,000 of the transcripts are noncoding RNAs. Researchers categorize these transcripts as microRNAs(miRNAs), piwi-interacting RNAs (piwiRNAs), small interfering RNAs (siRNAs) and lncRNAs. The first three types of RNAs are relatively small in size and play a role in regulating gene expression.

Figure 1: Transcription and Translation. Image credit: Shutterstock

Initially, researchers thought for the most part that lncRNAs were transcriptional noise—junk. But this view has changed in recent years. Evidence continues to accrue demonstrating that lncRNAs play a wide range of roles in the cell.¹ And as evidence for the utility of lncRNAs mounts, the case for the design of the human genome expands.

The Functional Utility of Long Noncoding RNAs

As it turns out, lncRNAs are extremely versatile molecules that can interact with: (1) other RNA molecules, (2) DNA, (3) proteins, and (4) cell membranes. This versatility opens up the possibility that these molecules play a diverse role in cellular metabolism.

Recently, Harry Krause, a molecular geneticist from the University of Toronto, published two review articles summarizing the latest insights into lncRNA function. These insights, including the four to follow, demonstrate the functional pervasiveness of the transcripts.

lncRNAs regulate gene expression. lncRNAs influence gene expression by a variety of mechanisms. One is through interactions with other transcripts forming RNA-RNA duplexes that typically interfere with translation of protein-coding messenger RNAs.

Researchers have recently learned that lncRNAs can also influence gene expression by interacting with DNA. These interactions result in either: (1) a triple helix, made up of two DNA strands intertwined with one RNA strand, or (2) a double helix with the lncRNA intertwined with one of the DNA strands, leaving the other exposed as a single strand. When these duplexes form, the lncRNA forms a hairpin loop that can either indiscriminately or selectively attract transcription factors.

Figure 2: A Hairpin Loop. Image credit: Wikipedia

Though researchers are still learning about the role lncRNAs play in gene regulation, these varied interactions with DNA and proteins suggest that lncRNAs may influence gene expression through a variety of mechanisms.

lncRNAs form microbodies within the nucleus and cytoplasm. A second function recognizes that lncRNAs interact with proteins to form hydrogel-like structures in the nucleus and cytoplasm. These structures are dense and heavily cross-linked subcellular structures that serve as functionally specific regions without a surrounding membrane. (In a sense, the microbodies could be viewed as somewhat analogous to ribosomes, the protein-RNA complexes that synthesize proteins.) In the nucleus, microbodies play a role in transcriptional processing, storage, and stress response. In the cytoplasm, microbodies play a role in storage, processing, and trafficking.

lncRNAs interact with cell membranes. A third role stems from laboratory studies where lncRNAs have been shown to interact with model cell membranes. Such interactions suggest that lncRNAs may play a role in mediating biochemical processes that take place at cell membranes. Toward this end, researchers have recently observed certain lncRNA species interacting with phosphatidylinositol 3,4,5-triphosphate. This cell membrane component plays a central role in signal transduction inside cells.

lncRNAs are associated with exosomes. Finally, lncRNAs have been found inside membrane-bound vesicles that are secreted by cells (called exosomes). These vesicles mediate cell-cell communication.

In short, the eyes of the scientific community have been opened. And they now see the functional importance and functional diversity of lncRNAs. Given the trend line, it seems reasonable to think that the functional range of lncRNAs will only expand as researchers continue to study the human genome (and genomes of other organisms).

The growing recognition of the functional versatility of lncRNAs aligns with studies demonstrating that other regions of the genome—long thought to be nonfunctional—do, in fact, play key roles in gene expression and other facets of cellular metabolism. Most significantly, toward this end, the functional versatility of lncRNAs supports the conclusions of the ENCODE Project—conclusions that have been challenged by some people in the scientific community.

The ENCODE Project

A program carried out by a consortium of scientists with the goal of identifying the functional DNA sequence elements in the human genome, the ENCODE Project, reported phase II results in the fall of 2012. (Currently, ENCODE is in phase IV.) To the surprise of many, the ENCODE Project reported that around 80 percent of the human genome displays biochemical activity—hence, function—with the expectation that this percentage should increase as results from phases III and IV of the project are reported.

The ENCODE results have generated quite a bit of controversy. One of the most prominent complaints about the ENCODE conclusions relates to the way the consortium determined biochemical function. Critics argue that ENCODE scientists conflated biochemical activity with function. As a case in point, the critics argue that most of the transcripts produced by the human genome (which include lncRNAs) must be biochemical noise. This challenge flows out of predictions of the evolutionary paradigm. Yet, it is clear that the transcripts produced by the human genome are functional, as numerous studies on the functional significance of lncRNAs attest. In other words, the biochemical activity detected by ENCODE equates to biochemical function—at least with respect to transcription.

A New View of Genomes

These types of insights are radically changing scientists’ view of the human genome. Rather than a wasteland of junk DNA sequences stemming from the vestiges of an evolutionary history, genomes appear to be incredibly complex, sophisticated biochemical systems, with most of the genome serving useful and necessary functions.

We have come a long way from the early days of the human genome project. When completed in 2003, many scientists at that time estimated that around 95 percent of the human genome consists of junk DNA. That acknowledgment seemingly provided compelling evidence that humans must be the product of an evolutionary history.

Nearly 15 years later the evidence suggests that the more we learn about the structure and function of genomes, the more elegant and sophisticated they appear to be. It is quite possible that most of the human genome is functional.

For creationists and intelligent design proponents, this changing view of the human genome—similar to discovering exciting new features of an iPhone—provides reasons to think that it is the handiwork of our Creator. A skeptic might ask, Why would a Creator make genomes littered with so much junk? But if a vast proportion of genomes consists of functional sequences, this challenge no longer carries weight and it becomes more and more reasonable to interpret genomes from within a creation model/intelligent design framework.

Resources

• “ENCODE Junks Evolutionary Concept” by Fazale Rana (article)
• “Responding to ENCODE Skeptics” by Fazale Rana (article)
• “Do ENCODE Skeptics Protest Too Much? Part 1” by Fazale Rana (article)
• “Do ENCODE Skeptics Protest Too Much? Part 2” by Fazale Rana (article)
• “Do ENCODE Skeptics Protest Too Much? Part 3” by Fazale Rana (article)
• “Do Scientists Accept the Results of the ENCODE Project?” by Fazale Rana (article)
• “Is 75 Percent of the Human Genome Junk DNA?” by Fazale Rana (article)
• “The Human Genome: Copied by Design” by Fazale Rana (article)
• “Protein Binding Sites ENCODEd into the Design of the Human Genome” by Fazale Rana (article)
• Who Was Adam? A Creation Model Approach to the Origin of Humanity, 2nd expanded ed., by Fazale Rana with Hugh Ross (book)

“It was said that some scientists attended the oxidative phosphorylation sessions of the Federation meetings because they knew a good punch up was on the cards.”

—John Prebble, Department of Biological Sciences, University of London

It has been described as one of the most “heated and acrimonious debates in biochemistry during the twentieth century,”¹ and its resolution carries implications for a different ideological conflict—that of the origin of life.

This battle royale (dubbed the Ox Phos Wars) took place in the 1960s and early 1970s. At that time, biochemists were trying to decipher the mechanism used by mitochondria to produce the high-energy compound called ATP (adenosine triphosphate) through a process called oxidative phosphorylation (Ox Phos for short). Many components of the cell’s machinery use ATP to power their operations.

Figure 1: A schematic of the synthesis and breakdown cycle of ATP and ADP. Image credit: Shutterstock

So acrimonious was the debate that scientists involved in this controversy often came close to blows when publicly debating the mechanism of oxidative phosphorylation. Much of the controversy centered around an idea known as the chemiosmotic theory, proposed by biochemist Peter Mitchell. He argued that the electron transport chain generates a proton gradient across the mitochondrial inner membrane and, in turn, exploits that gradient through a coupling process to drive the synthesis of ATP from ADP (adenosine diphosphate) and inorganic phosphate. (see figures 1 and 2). (The reverse reaction liberates chemical energy that drives many biochemical processes.)

Figure 2: A schematic of the chemiosmotic theory. Image credit: Shutterstock

At the time, this idea was met with a large measure of skepticism by biochemists. It didn’t fit with the orthodoxy, characteristic of classical biochemistry. Biochemists found Mitchell’s ideas hard to understand and his personality abrasive, both of which led to the acrimony.

Origin-of-life researcher Leslie Orgel referred to the chemiosmotic theory as one of the most counterintuitive ideas to ever come out of biology, comparing it to the ideas that formed the foundations of quantum mechanics and relativity.²

Many biochemists preferred the chemical theory of oxidative phosphorylation over Mitchell’s chemiosmotic theory. Researchers thought that the phosphate group added to ADP was transferred from one of the components of the electron transport chain. In an attempt to support this idea, many biochemists frantically searched for a chemical intermediate with a high-energy phosphate moiety that could power the synthesis of ATP.

The chemical theory was based on a process called substrate-level phosphorylation, exemplified by two reactions that form ATP during glycolysis. In one reaction, 1,3-diphosphoglycerate transfers one of its phosphate groups to ADP to form ATP. (In this case, 3-diphosphoglycerate serves as the intermediate with a high-energy phosphate moiety.) In the second reaction, phosphoenolpyruvate transfers a phosphate group to ADP to make ATP, with phosphoenolpyruvate functioning as the intermediate bearing a high-energy phosphate residue. (See figure 3.)

As it turns out, the elusive intermediate was never found, forcing adherents of the chemical theory to abandon their model. Peter Mitchell’s idea won the day. In fact, Mitchell was awarded the Nobel Prize in Chemistry in 1978 for his contribution to understanding the mechanism of oxidative phosphorylation.

Today, biochemists readily recognize the importance of proton gradients and the chemiosmotic process. Proton gradients are pervasive in living systems. Mitochondria are not alone. Chloroplasts rely on proton gradients during the process of photosynthesis. Bacteria and archaea also use proton gradients across their plasma membranes to harvest energy. Cells use proton gradients to transport material across cell membranes. And proton gradients even power the bacterial flagellum.

Now that oxidative phosphorylation is understood, some evolutionary biologists and origin-of-life researchers have turned their attention to two questions: (1) How did chemiosmosis originate? and (2) Why are proton gradients so central to biochemical operations?

Oxidative Phosphorylation and the Evolutionary Paradigm

For many evolutionary biologists, understanding the origin of oxidative phosphorylation (and the use of proton gradients, in general) assumes a position of unique prominence because of the central role this process plays in harvesting energy in both prokaryotic and eukaryotic organisms. In other words, understanding the origin of oxidative phosphorylation (and use of proton gradients) is central to understanding the origin of life and the fundamental design of biochemical systems.

Because the use of proton gradients in living systems is odd and counterintuitive, it becomes tempting for many origin-of-life researchers and evolutionary biologists to conclude that chemiosmosis reflects the outworking of a historically contingent evolutionary process that relied on existing systems and designs that were co-opted and, in turn, modified. This notion becomes reinforced by the work of origin-of-life researcher Nick Lane.

Lane and his collaborators conclude that proton gradients must have been integral to the biochemistry of LUCA (the last universal common ancestor) because proton gradients are a near-universal feature of living systems. If so, then the use of proton gradients must have emerged during the origin-of-life process before LUCA originated. Lane and his team go so far as to propose that the first proto-cells emerged near hydrothermal vents and made use of naturally occurring proton gradients found in these environments as their energy source.³

Once this system was in place, the strategy was retained in the cell lines that diverged from these early proto-cellular entities as the electron transport chain evolved from a simple, naturally occurring vent process to the complex process found in both prokaryotic and eukaryotic organisms. In other words, it would seem that the odd, counterintuitive nature of proton gradients reflects the happenstance outworking of chemical evolution that began when the naturally occurring proton gradients were co-opted in the early stages of chemical evolution.

But Lane’s recent insight indicates that, though counterintuitive, the use of proton gradients to harvest the energy required to make ATP makes sense, displaying an exquisite molecular rationale.⁴ And if so, it forces a rethink of the explanation for the origin of chemiosmosis. To appreciate this shift in perspective, it is helpful to understand the process of oxidative phosphorylation, beginning with glycolysis and the Kreb’s cycle.

Glycolysis and the Kreb’s Cycle

The glycolytic pathway converts the fuel molecule glucose (a 6-carbon sugar) into two pyruvate molecules (3-carbon). This process proceeds through eleven chemical intermediates and nets 2 molecules of ATP (generated through substrate-level phosphorylation) and two molecules of NADH (nicotinamide adenine dinucleotide). NADH harbors high-energy electrons generated from the energy liberated from the breakdown and oxidation of glucose. As it turns out, the NADH molecules play a central role in generating most of the ATP produced when a sugar molecule breaks down.

Figure 3: Glycolysis. Image credit: Shutterstock

The pyruvate generated by glycolysis is transported across the mitochondrial inner membrane into the matrix of the organelle. Here pyruvate is transformed into a molecule of carbon dioxide and a 2-carbon intermediate called acetyl CoA. This process generates 2 additional molecules of NADH.

In turn, the Kreb’s cycle converts each acetyl CoA molecule into two molecules of carbon dioxide. (The net reaction: a 6-carbon glucose molecule breaks down into 6 carbon dioxide molecules.) During the process, the breakdown of each acetyl CoA molecule generates 1 ATP molecule (via substrate-level phosphorylation) and 3 molecules of NADH. Additionally, 1 molecule of FADH₂ is formed. Like NADH, this molecule possesses high-energy electrons. (See figure 4.)

Figure 4: Kreb’s cycle. Image credit: Shutterstock

The Electron Transport Chain and Oxidative Phosphorylation

The high-energy electrons of NADH and FADH₂ are transferred to the electron transport chain, which is embedded in the inner membrane.

Four protein complexes (dubbed I, II, III, and IV) make up the electron transport chain. The high-energy electrons from NADH and FADH₂ are shuffled from one protein complex to the next, with each transfer releasing energy that is used to transport protons from the mitochondrial matrix across the inner membrane, establishing the proton gradient. (See figure 5.) Oxygen is the final electron acceptor in the electron transport chain. The electrons transferred to oxygen lead to the formation of a water molecule.

Because protons are positively charged, the exterior region outside the inner membrane is positively charged and the interior region is negatively charged. The charge differential created by the proton gradient is analogous to a battery and the inner membrane is like a capacitor.

Figure 5: Electron Transport Chain. Image credit: Shutterstock

The coupling of the proton gradient to ATP synthesis occurs as a result of the flow of positively charged protons through the F₀ component of a protein complex called F₁-F₀ATPase (also embedded in the mitochondrial inner membrane). F₁-F₀ATPase uses this flux to convert electrochemical energy into mechanical energy that, in turn, is used to drive the formation of ATP from ADP and inorganic phosphate.

The Molecular Logic of Proton Gradients

So, why are chemiosmosis and proton gradients universal features of living systems? Are they an outworking of a historically contingent evolutionary process? Or is there something more at work?

Even though proton gradients seem counterintuitive at first glance, the use of proton gradients to power the production of ATP and other cellular processes reflects an underlying ingenuity and exquisite molecular logic. Research shows that proton gradients allow the cell to efficiently extract as much energy as possible from the breakdown of glucose (and other biochemical foodstuffs).5 On the other hand, if ATP was produced exclusively by substrate-level phosphorylation, using a high-energy chemical intermediate, much of the energy liberated from the breakdown of glucose would be lost as heat.

To understand why this is so, consider this analogy. Suppose people in a particular community receive their daily allotment of water in a 10-gallon bucket. The water they receive each day is retrieved from a reservoir with a 12-gallon bucket and then transferred to their bucket. In the process, two gallons of water is lost. Now, suppose the water from the reservoir is retrieved with a 12-gallon bucket but dumped into a secondary reservoir that has a tap. The tap allows each 10-gallon bucket to be filled without losing two gallons. Though the procedure is indirect and more complicated, using the secondary reservoir to distribute water is more efficient in the long run. In the first scenario, it takes 60 gallons of water (transferred from the reservoir in five 12-gallon buckets) to fill up five 10-gallon buckets. In the second scenario, the same amount of water transferred from the reservoir can fill six 10-gallon buckets. With each transfer, the additional two gallons accumulate in the reservoir until there is enough water to fill another 10-gallon bucket.

With substrate-level phosphorylation, when the phosphate group is transferred from the high-energy intermediate to ADP to form ATP, excess energy released during the transfer is lost as heat. It takes 7 kcal/mole of energy to add a phosphate group to ADP to form ATP. Let’s say that the hypothetical chemical intermediate releases 10 kcal/mole when its high-energy phosphate bond is broken. Three kcal/mole of energy is lost.

On the other hand, using the electron transport chain to build up a proton gradient is like the reservoir in our analogy. It allows that extra three kcal/mole to be stored in the proton gradient. We can think of the F₁-F₀ATPase as analogous to the tap. It uses 7 kcal/mole of energy released when protons flow through its channels to drive the formation of ATP from ADP and inorganic phosphate. The unused energy from the proton gradient continues to accumulate until enough energy is available to form another ATP molecule. So, in our hypothetical scenario, if the cell used substrate-level phosphorylation to make ATP, 70 molecules of the high-energy intermediate would yield 70 molecules of ATP with 210 kcal/mole of energy released as heat. But, using the electron transport chain to generate proton gradients yields 100 ATP molecules with no energy lost as heat.

Chemiosmotic Theory and the Case for Creation

The elegant molecular rationale that undergirds the use of proton gradients to harvest energy and to power certain cellular processes makes it unlikely that this biochemical feature reflects the outcome of a historically contingent process that just happened upon proton gradients. Instead, it points to a set of principles that underlie the structure and function of biochemical systems—principles that appear to have been set in place from the beginning of the universe.

The most obvious and direct way for the first protocells to harvest energy would seemingly involve some type of mechanism that resembled substrate-level phosphorylation, not an indirect and more complicated mechanism that relies on proton gradients. If the origin of chemiosmosis and the use of proton gradients was, indeed, a historically contingent outcome—predicated on the fact that the first protocells just happened to employ a natural proton gradient—it seems almost eerie to think that evolutionary processes blindly stumbled upon what would later become such an elegant and efficient energy-harvesting process. And a process necessary for advanced life to be possible on Earth.

If not for chemiosmosis, it is unlikely that eukaryotic cells and, hence, complex life such as animals, plants, and fungi, could have ever existed. Substrate-level phosphorylation just isn’t efficient enough to support the energy demands of eukaryotic organisms.

It is also difficult to imagine how the natural proton gradients exploited by the first protocells could have been co-opted and then evolved so quickly into the complex components of the electron transport chain and F₁-F₀ATPase coupling mechanism found in cells that preceded LUCA. Not only are the components of the electron transport chain complex, but they have to work together in an integrated manner to establish the proton gradient across mitochondrial membranes (and the plasma membranes of bacteria and archaea). Without the existence of the F₁-F₀ATPase (or some other mechanism) to couple proton gradients to the synthesis of ATP, the generation of proton gradients would be for naught. The origin of the electron transport chain and F₁-F₀ATPase have to coincide.

On the other hand, the ingenious use of proton gradients and the elegant molecular logic that accounts for their universal use by living systems are exactly the features I would expect if life stems from the work of a Mind. Moreover, the architecture and operation of complex I and F₁-F₀ATPase add to the case for creation. These two complexes are molecular motors that bear an startling similarity to man-made machines, revitalizing the Watchmaker argument for God’s existence.

As noted, the use of proton gradients points to a set of deep, underlying principles that arise from the very nature of the universe itself and dictate how life must be. The molecular rationale that undergirds the use of proton gradients and their near-universal occurrence in living organisms suggests that proton gradients are an indispensable feature of living organisms. In other words, without the use of proton gradients to harvest energy and drive cellular processes, advanced life would not be possible. Or another way to say it: if life was discovered elsewhere in the universe, it would have to employ proton gradients to harvest energy.

It is remarkable to think that proton gradients, which are a manifestation of the laws of nature, are, at the same time, precisely the type of system advanced life needs to exist. One way to interpret this “coincidence” is that it serves as evidence that our universe has been designed for a purpose.

And as a Christian, I find that notion to resonate powerfully with the idea that life manifests from an intelligent Agent—namely, God.

Resources

• The Cell’s Design: How Chemistry Reveals the Creator’s Artistry by Fazale Rana (Book)
• “Electron Transport Chain Protein Complexes Rev Up the Case for Design” by Fazale Rana (article)
• “Reactive Oxygen Species: Harbingers of Evolution or Signals of Design?” by Fazale Rana (article)
• “A Periodic Table for Protein Structure Reveals Biochemical Design” by Fazale Rana (article)

Comic books intrigue me. They are a powerful storytelling vehicle. The combination of snapshot-style imagery, along with narration and dialogue, allows the writer and artist to depict action and emotion in a way that isn’t possible using the written word alone. Comic books make it easy to depict imaginary worlds. And unlike film, comics engage the reader in a deeper, more personal way. The snapshot format requires the reader to make use of their imagination to fill in the missing details. In this sense, the reader becomes an active participant in the storytelling process.

In America, comics burst onto the scene in the 1930s, but the oldest comics (at least in Europe) trace their genesis to Rodolphe Töpffer (1799-1846). Considered by many to be “the father of comics,” Töpffer was a Swiss teacher, artist, and author who became well-known for his illustrated books—works that bore similarity to modern-day comics.

Despite his renown, Töpffer wasn’t the first comic book writer and artist. That claim to fame belongs to long forgotten artists from prehistory. In fact, recent work by Australian and Indonesian researchers indicates that comics as a storytelling device dates to earlier than 44,000 years ago.

Seriously!

These investigators discovered and characterized cave art from a site on the Indonesian island of Sulawesi that depicts a pig and buffalo hunt. Researchers interpret this mural to be the oldest known recorded story¹ —a comic book story on a cave wall.

This find, and others like it, provide important insight into our origins as human beings. From my perspective as a Christian apologist, this discovery is important for another reason. I see it as affirming the biblical teaching about humanity: God made human beings in his image.

The Find

Leading up to this discovery, archeologists had already identified and dated art on cave walls in Sulawesi and Borneo. This art, which includes hand stencils and depictions of animals, dates to older than 40,000 years in age and is highly reminiscent of the cave art of comparable age found in Europe.

In December 2017, an archeologist from Indonesia discovered the hunting mural in a cave (now called Leang Bulu’ Sipong 4) in the southern part of Sulawesi. The panel presents the viewer with an ensemble of pigs and small buffalo (called anoas), endemic to Sulawesi. Most intriguing about the artwork is the depiction of smaller human-like figures with animal features such as tails and snouts. In some instances, the figures appear to be holding spears and ropes. Scholars refer to these human-animal depictions as therianthropes.

Dating the Find

Dating cave art can be notoriously difficult. One approach is to directly date the charcoal pigments used to make the art using radiocarbon methods. Unfortunately, the dates measured by this technique can be suspect because the charcoal used to make the art can be substantially older than the artwork itself.

Recently, archeologists have developed a new approach to date cave art. This method measures the levels of uranium and thorium in calcite deposits that form on top of the artwork. Calcite is continuously deposited on cave walls due to hydrological activity in the cave. As water runs down the cave walls, calcium carbonate precipitates onto the cave wall surface. Trace amounts of radioactive uranium are included in the calcium carbonate precipitates. This uranium decays into thorium, hence the ratio of uranium to thorium provides a measure of the calcite deposit’s age and, in turn, yields a minimum age for the artwork.

To be clear, this dating method has been the subject of much controversy. Some archeologists argue that the technique is unreliable because the calcite deposits are an open system. Once the calcite deposit forms, water will continue to flow over the surface. The water will solubilize part of the calcite deposit and along with it the trace amounts of uranium and thorium. Thus, because uranium is more soluble than thorium we get an artificially high level of thorium. So, when the uranium-thorium ratio is measured, it may make it appear as if the cave art is older than it actually is.

To ensure that the method worked as intended, the researchers only dated calcite deposits that weren’t porous (which is a sign that they have been partially re-dissolved) and they made multiple measurements from the surface of the deposit toward the interior. If this sequence of measurements produced a chronologically consistent set of ages, the researchers felt comfortable with the integrity of the calcite samples. Using this method, the researchers determined that the cave painting of the pig and buffalo hunt dates to older than 43,900 years.

Corroborating evidence gives the archeologists added confidence in this result. For example, the discovery of archeological finds in the Sulawesi cave site that were independently dated indicate that modern humans were in the caves between 40,000 to 50,000 years ago, in agreement with the measured age of the cave art.

The research team also noted that the animal and the therianthropes in the mural appear to have been created at the same time. This insight is important because therianthropes don’t appear in the cave paintings found in Europe until around 10,000 years ago. This observation means that it is possible that the therianthropes could have been added to the painting millennia after the animals were painted onto the cave wall. However, the researchers don’t think this is the case for at least three reasons. First, the same artistic style was used to depict the animals and therianthropes. Second, the technique and pigment used to create the figures is the same. And third, the degree of weathering is the same throughout the panel. None of these features would be expected if the therianthropes were a late addition to the mural.

Interpreting the Find

The researchers find the presence of therianthropes in 44,000+ year-old cave art significant. It indicates that humans in Sulawesi not only possessed the capacity for symbolism, but, more importantly, had the ability to conceive of things that did not exist in the material world. That is to say, they had a sense of the supernatural.

Some archeologists believe that the cave art reflects shamanic beliefs and visions. If this is the case, then it suggests that the therianthropes in the painting may reflect spirit animal helpers who ensured the success of the hunt. The size of the therianthropes supports this interpretation. These animal-human hybrids are depicted as much smaller than the pigs and buffalo. On the island of Sulawesi, both the pig and buffalo species in question were much smaller than modern humans.

Because this artwork depicts a hunt involving therianthropes, the researchers see rich narrative content in the display. It seems to tell a story that likely reflected the mythology of the Sulawesi people. You could say it’s a comic book on a cave wall.

Relationship between Cave Art in Europe and Asia

Cave art in Europe has been well-known and carefully investigated by archeologists and anthropologists for nearly a century. Now archeologists have access to a growing archeological record in Asia.

Art found at these sites is of the same quality and character as the European cave art. However, it is older. This discovery means that modern humans most likely had the capacity to make art even before beginning their migrations around the world from out of Africa (around 60,000 years ago).

As noted, the discovery of therianthropes at 44,000+ years in age in Sulawesi is intriguing because these types of figures don’t appear in cave art in Europe until around 10,000 years ago. But archeologists have discovered the lion-man statue in a cave site in Germany. This artifact, which depicts a lion-human hybrid, dates to around 40,000 years in age. In other words, therianthropes were part of the artwork of the first Europeans. It also indicates that modern humans in Europe had the capacity to envision imaginary worlds and held belief in a supernatural realm.

Capacity for Art and the Image of God

For many people, our ability to create and contemplate art serves as a defining feature of humanity—a quality that reflects our capacity for sophisticated cognitive processes. So, too, does our capacity for storytelling. As humans, we seem to be obsessed with both. Art and telling stories are manifestations of symbolism and open-ended generative capacity. Through art (as well as music and language), we express and communicate complex ideas and emotions. We accomplish this feat by representing the world—and even ideas—with symbols. And, we can manipulate symbols, embedding them within one another to create alternate possibilities.

As a Christian, I believe that our capacity to make art and to tell stories is an outworking of the image of God. As such, the appearance of art (as well as other artifacts that reflect our capacity for symbolism) serves as a diagnostic for the image of God in the archeological record. That record provides the means to characterize the mode and tempo of the appearance of behavior that reflect the image of God. If the biblical account of human origins is true, then I would expect that artistic expression should be unique to modern humans and should appear at the same time that we make our first appearance as a species.

So, when did art (and symbolic capacity) first appear? Did art emerge suddenly? Did it appear gradually? Is artistic expression unique to human beings or did other hominins, such as Neanderthals, produce art too? Answers to these questions are vital to our case for human exceptionalism and, along with it, the image of God.

When Did the Capacity for Art First Appear?

Again, the simultaneous appearance of cave art in Europe and Asia indicates that the capacity for artistic expression (and, hence, symbolism) dates back to the time in prehistory before humans began to migrate around the world from out of Africa (around 60,000 years ago). This conclusion gains support from the recent discovery of a silcrete flake from a layer in the Blombos Cave that dates to about 73,000 years old. (The Blombos Cave is located around 150 miles east of Cape Town, South Africa.) A portion of an abstract drawing is etched into this flake.²

Linguist Shigeru Miyagawa believes that artistic expression emerged in Africa earlier than 125,000 years ago. Archeologists have discovered rock art produced by the San people that dates to 72,000 years ago. This art shares certain elements with European cave art. Because the San diverged from the modern human lineage around 125,000 years ago, the ancestral people groups that gave rise to both lines must have possessed the capacity for artistic expression before that time.³

It is also significant that the globular brain shape of modern humans first appears in the archeological record around 130,000 years ago. As I have written about previously, globular brain shape allows expansion of the parietal lobe, which is responsible for many of our capacities:

• Perception of stimuli
• Sensorimotor transformation (which plays a role in planning)
• Visuospatial integration (which provides hand-eye coordination needed for making art)
• Imagery
• Self-awareness
• Working and long-term memory

In other words, the evidence indicates that our capacity for symbolism emerged at the time that our species first appears in the fossil record. Some archeologists claim that Neanderthals displayed the capacity for symbolism as well. If this claim proves true, then human beings don’t stand apart from other creatures. We aren’t special.

Did Neanderthals Have the Capacity to Create Art?

Claims of Neanderthal artistic expression abound in popular literature and appear in scientific journals. However, a number of studies question these claims. When taken as a whole, the evidence indicates that Neanderthals were cognitively inferior to modern humans.

So, when the evidence is considered as a whole, only human beings (modern humans) possess the capability for symbolism, open-ended generative capacity, and theory of mind—in my view, scientific descriptors of the image of God. The archeological record affirms the biblical view of human nature. It is also worth noting that the origin of our symbolic capacity seems to arise at the same time that modern humans appear in the fossil record, an observation I would expect given the biblical account of human origins.

Like the comics that intrigue me, this narrative resonates on a personal level. It seems as if the story told in the opening pages of the Old Testament is true.

Resources

• Fazale Rana with Hugh Ross, Who Was Adam? A Creation Model Approach to the Origin of Humanity, 2nd exp. ed. (Reasons to Believe: Covina, CA, 2015).

Cave Art and the Image of God

• “Early Cave Art Supports the Image of God” by Fazale Rana (article)
• “Sophisticated Cave Art Evinces the Image of God” by Fazale Rana (article)
• “Prehistoric Artists Better Than Moderns” by Fazale Rana (article)
• “New Archeological Evidence Fills the Gap in the Biblical Case for Human Origins” by Fazale Rana (article)
• “The Oldest Art in the World” by Fazale Rana (article)

The Modern Human Brain

• “When Did Modern Human Brains and the Image of God Appear?” by Fazale Rana (article)
• “Brain Synchronization Study Evinces the Image of God” by Fazale Rana (article)

Could Neanderthals Make Art?

• “Differences in Human and Neanderthal Brains Explain Human Exceptionalism” by Fazale Rana (article)
• “Did Neanderthals Have the Brains to Make Art?” by Fazale Rana (article)
• “Further Review Overturns Neanderthal Art Claim” by Fazale Rana (article)
• “Timing of Neanderthals’ Disappearance Makes Art Claims Unlikely” by Fazale Rana (article)

Update on the COVID-19 Pandemic, March 17, 2020

Conditions change rapidly with a viral outbreak, and people sometimes wonder where to find good sources of information. To that end, I hope that a review of pertinent scientific data combined with personal encouragement will help you and those close to you be as informed as possible.

My Professional Background

I worked with a small team of dedicated scientists studying SARS-CoV at the National Institutes of Health (NIH) during the SARS (severe acute respiratory syndrome) outbreak of 2003. In my three years (2003–06) at the NIH we completed more than 50 projects that involved developing animal models for studying SARS pathogenesis and testing a variety of potential vaccines and treatments for SARS. We were successful in all these studies. And although we identified several good candidates for vaccines and prophylaxis, none were tested in human trials because SARS disappeared as fast as it appeared.

Viral Comparisons

There are a lot of similarities between the SARS virus and the novel coronavirus (nCOV-2019) that everyone is talking about. The similarities are such that this new virus has been officially named SARS-CoV-2 (hereafter SARS-2). The disease it causes has been named COVID-19 (coronavirus infectious disease 2019).

But there are also important differences between SARS-2 and SARS, other coronaviruses, and other viruses like influenza A and B (flu).

Both SARS-2 and SARS are coronaviruses—the name given to a family of viruses with shared genetic and structural characteristics. Coronavirus genomes are comprised of RNA, and as far as RNA viruses go, coronaviruses are among the largest. SARS virus particles measure 150–200 nanometers (nm) in diameter and the viral genome is roughly 30,000 bases. Structurally, the surfaces of these tiny virus particles look a little like a crown with viral proteins (spikes) protruding from the cell-derived membrane that surrounds the viral nucleocapsids. The spike proteins are what the virus uses to attach to cells, enter cells, and initiate infection.

Some Viral History

Before SARS the only known coronaviruses that infected humans (HCoV-229E and -OC43) were both associated with cold-like symptoms and upper respiratory infections. Coronaviruses, including those that infect other animals, are frequently associated with respiratory and/or gastrointestinal symptoms. Unlike these other coronaviruses, SARS was a surprise because the severe atypical pneumonia that resulted from infection led to death in about 10% of cases, and 20–30% of SARS-infected individuals required mechanical ventilation. From November 2002 through July 2003, SARS spread to 27 countries, infecting nearly 8,100 people and killing 774. The fatality rate was much higher for the elderly (over the age of 50, the risk of severe disease and death increased with each decade of life) and for those who had additional, underlying diseases such as diabetes mellitus, hypertension, and heart or kidney disease.

Following the SARS outbreak, screening for additional coronaviruses in patients with respiratory illness led to the discovery of two other coronaviruses circulating in the human population (NL63 and HKU1). NL63, HKU1, OC43, and 229E coronaviruses account for 10–30% of upper respiratory infections in adults.

In 2012 there was another coronavirus outbreak in the Arabian Peninsula. The virus, like SARS, led to severe atypical types of pneumonia and was dubbed MERS (Middle Eastern respiratory syndrome) coronavirus. As of November 2019, the cumulative case count for MERS is 2,494 with 858 fatalities, yielding a mortality rate of about 35%. Again, higher mortality is seen in the elderly and in those with underlying conditions. Diabetes mellitus, hypertension, cardiac diseases, renal disease, and bronchial asthma have been the most frequent comorbid (simultaneous) disorders. Following MERS infection, 50–89% of patients require mechanical ventilation support.

SARS and MERS coronaviruses spread to the human population from animals harboring the virus. In the case of SARS, a weasel-like animal known as a civet cat or palm civet was the culprit. In MERS, contact with infected dromedary camels introduces the virus into the human population where it spreads poorly from person-to-person. The environmental reservoir for SARS-2 (COVID-19) virus has not been identified, but there is a very high sequence similarity to bat coronaviruses.

SARS-2 virus, like SARS and MERS coronaviruses, also has a higher mortality rate in the elderly and those with underlying disease. Unlike SARS and MERS, SARS-2 has a much lower overall mortality rate. Thus far (data from March 17, 2020) SARS-2 has infected over 190,000 people in over 55 countries in about 4 months’ time. The number of reported fatalities is just over 7,500, which coincides with an overall mortality rate of 3.5–4%. In some countries where the virus has been circulating for a few weeks, the mortality rates vary from 0.98% in South Korea to 7.7% in hard-hit Italy (these numbers were 0.64% and 2.5%, respectively, on March 2). It is still early in the pandemic, so global and individual country rates may change.

How Can You Help Prevent Spread of SARS-2?

The US travel restrictions put in place on February 2 almost certainly helped delay the spread of SARS-2 in the US. Calls for communities to practice social distancing and sheltering in place will also slow the spread. Limiting discretionary travel and meetings of large groups of people will also help slow the spread. These are the best practices for each of us and, along with practicing good personal and environmental hygiene, these will make huge differences in the ultimate outcome.

Our goal is to slow and limit the spread. This will help our health system infrastructure continue to manage influenza hospitalizations while limiting COVID cases. Flu season usually ends in April/May, so a few weeks’ delay and a slow community spread of COVID cases will improve outcomes. Slowing the spread will also help maintain resource availability for testing and treating the infected.

Facial masks are critical for health care personnel and most people in the general public do not use them properly. Rather than deplete a precious resource that will keep our health care system working for the benefit of us all, leave the masks for the professionals who need them. If you’re sick, you should be self-isolating and will not need a mask.

The best way to prevent the spread of SARS-2 (and flu) based on knowledge garnered from the 2003 SARS outbreak and subsequent studies on SARS and respiratory viruses includes the following:

• Frequently wash your hands with warm soapy water to a lather for 30 seconds.
• Avoid touching your face (mouth, nose, eyes).
• Use freshly prepared bleach, diluted 1:10 or 1:5 with water, to spray surfaces. Let air dry then wipe them down.
• Use hand sanitizers if washing your hands is not an option.

SARS-2 Is More Challenging Than SARS in Some Ways

SARS and SARS-2 have different incubation periods than flu. During the SARS outbreak most infected individuals demonstrated symptoms within 5 days of infection. Virus could be detected in SARS-infected individuals up to 30 days (rarely, even longer) post-infection. In contrast, the estimated incubation period for SARS-2 is up to 14 days and the recovery period is highly variable, from days up to weeks. In both cases, the viruses can be spread by infected individuals who are not showing signs of illness, but this seems to be more common with SARS-2 than it was for SARS.

Influenza viruses are in a different virus family than the coronaviruses and have smaller, segmented RNA genomes (about 14,000 bases) and smaller virus particles (about 100 nm in diameter). Influenza has an average incubation period of 2 days and it may be spread while asymptomatic between days 1 and 2 post-infection. Flu patients typically recover within 5–7 days.

SARS virus spreads through contact and respiratory droplets (generated by sneezing, coughing, and speaking) and was isolated from saliva, sweat, tears, urine, and feces. Influenza viruses are also spread by contact and respiratory droplets. Contact refers to coming in contact with virus deposited on surfaces of other items, such as door or refrigerator handles or elevator buttons or rails, and then touching your mouth, nose, or eyes. The potential for transmission by contact is linked to the virus’s ability to survive on contaminated surfaces. In regard to contact, SARS is more stable outside the body and on hard or dried surfaces than influenza viruses (see table).

The initial symptoms for SARS, SARS-2, and influenza viruses A and B are similar: cough, fever, and myalgia. Severe cases may progress to an acute respiratory distress syndrome, a severe type of pneumonia, resulting in hospitalizations and sometimes death.

Although SARS (and SARS-2) and influenza viruses may be spread by respiratory droplets and contact and may be difficult to distinguish from one another based on initial clinical symptoms, the viruses differ significantly from one another in very important ways. SARS (and due to greater biological similarity, possibly SARS-2) virus is much more durable in the environment than the influenza virus (see table below). These viruses also differ in their incubation periods, duration of illness, duration and means of viral shedding, and mortality rates. It is also likely that they vary in rates of transmission and in other factors affecting infectivity, transmission, tropism, pathogenicity, and recovery.

Precautions while Helping Others

Although a healthy adult under the age of 50 may experience very similar clinical symptoms if contracting SARS-2 or influenza virus, these viruses do not share the same biology, structure, or overall risks to the more vulnerable populations within our communities. Although the risk to many young healthy adults may not be as severe, they can become infected and transmit the virus to elderly individuals or to people with underlying risk factors. The latter two groups incur a greater risk of severe disease with SARS-2. All people need to take precautions to protect the most vulnerable among us. For Christians, it’s one way we can serve one another in love in the name of Christ Jesus.

Finally, I encourage you to meditate on scriptures such as Psalm 139, which reminds us that God is intimately acquainted with all our actions and is with us whatever we face. Other scriptures remind us of the call to love our neighbors even at great personal cost. I am always challenged when I remember that we are called to show mercy especially to the most marginalized individuals in society. In this context, part of that call entails that we take personal precautions while not abandoning those who are in greater need than we are. Love boldly and pray as you serve others in these challenging days.

Resources

Online source materials available at:

• World Health Organization, “Middle East Respiratory Syndrome Coronavirus (MERS-CoV),” November 2019, https://www.who.int/emergencies/mers-cov/en/.
• World Health Organization, “Emergencies Preparedness, Response: Summary of Probable SARS Cases with Onset of Illness from 1 November 2002 to 31 July 2003,” revised September 2003, https://www.who.int/csr/sars/country/table2003_09_23/en/.
• SR Weiss and S. Navas-Martin, “Coronavirus Pathogenesis and the Emerging Pathogen Severe Acute Respiratory Syndrome Coronavirus,” Microbiology and Molecular Biology Reviews, 69, no. 4 (December 2005): 635–64, https://www.ncbi.nlm.nih.gov/pubmed/16339739.
• “Coronavirus COVID-19 Global Cases by the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University,” accessed March 18, 2020, https://gisanddata.maps.arcgis.com/apps/opsdashboard/index.html?fbclid=IwAR1dcZxxg-3MZOWDYpQwn-4hEHUVs1WgPhFduklvjzZdAf6lvAESmUlKuIk#/bda7594740fd40299423467b48e9ecf6.
• Centers for Disease Control and Prevention, “2019–2020 U.S. Flu Season: Preliminary Burden Estimates,” March 7, 2020, https://www.cdc.gov/flu/about/burden/preliminary-in-season-estimates.htm.

References that populate the data table:

• B. Bean et al., “Survival of Influenza Viruses on Environmental Surfaces,” The Journal of Infectious Diseases, vol. 146, no. 1 (July 1982): 47–51, https://doi.org/10.1093/infdis/146.1.47.
• Jane S. Greatorex et al., “Survival of Influenza A(H1N1) on Materials Found in Households: Implications for Infection Control,” PLoS One 6, no. 11, (November 22, 2011):e27932, doi:10.1371/journal.pone.0027932.
• M. Lindsay Grayson et al., “Efficacy of Soap and Water and Alcohol-Based Hand-Rub Preparations against Live H1N1 Influenza Virus on the Hands of Human Volunteers.” Clinical Infectious Diseases 48, no. 3 (February 1, 2009): 285–91, https://doi.org/10.1086/595845.
• Shumei Zou et al., “Inactivation of the Novel Avian Influenza A (H7N9) Virus under Physical Conditions or Chemical Agents Treatment,” Virology Journal 10, no. 289 (September 15, 2013), doi:10.1186/1743-422X-10-289.
• G. Kampf et al., “Persistence of Coronaviruses on Inanimate Surfaces and Their Inactivation with Biocidal Agents,” Journal of Hospital Infection 104, no. 3 (March 2020): 246–51, https://www.journalofhospitalinfection.com/article/S0195-6701(20)30046-3/fulltext.
• Chloé Geller, Mihayl Varbanov, and Raphaël E. Duval, “Human coronaviruses: Insights into Environmental Resistance and Its Influence on the Development of New Antiseptic Strategies,” Viruses 4, no. 11 (November 12, 2012): 3044–68, doi:10.3390/v4113044.
• Anne-Marie Pagat et al., “Evaluation of SARS-Coronavirus Decontamination Procedures,” Applied Biosafety 12 no. 2 (June 1, 2007): 100–08, https://doi.org/10.1177/153567600701200206.
• SM Duan et al., “Stability of SARS Coronavirus in Human Specimens and Environment and Its Sensitivity to Heating and UV Irradiation,” Biomedical and Environmental Sciences 16, no. 3 (September 2003): 246–55, https://www.ncbi.nlm.nih.gov/pubmed/14631830.