Tag: william paley

But Do Watches Replicate? Addressing a Logical Challenge to the Watchmaker Argument

By Fazale Rana – January 22, 2020

Were things better in the past than they are today? It depends who you ask.

Without question, there are some things that were better in years gone by. And, clearly, there are some historical attitudes and customs that, today, we find hard to believe our ancestors considered to be an acceptable part of daily life.

It isn’t just attitudes and customs that change over time. Ideas change, too—some for the better, some for the worst. Consider the way doing science has evolved, particularly the study of biological systems. Was the way we approached the study of biological systems better in the past than it is today?

It depends who you ask.

As an old-earth creationist and intelligent design proponent, I think the approach biologists took in the past was better than today for one simple reason. Prior to Darwin, teleology was central to biology. In the late 1700s and early to mid-1800s, life scientists viewed biological systems as the product of a Mind. Consequently, design was front and center in biology.

As part of the Darwinian revolution, teleology was cast aside. Mechanism replaced agency and design was no longer part of the construct of biology. Instead of reflecting the purposeful design of a Mind, biological systems were now viewed as the outworking of unguided evolutionary mechanisms. For many people in today’s scientific community, biology is better for it.

Prior to Darwin, the ideas shaped by thinkers (such as William Paley) and biologists (such as Sir Richard Owen) took center stage. Today, their ideas have been abandoned and are often lampooned.

But, advances in my areas of expertise (biochemistry and origins-of-life research) justify a return to the design hypothesis, indicating that there may well be a role for teleology in biology. In fact, as I argue in my book The Cell’s Design, the latest insights into the structure and function of biomolecules bring us full circle to the ideas of William Paley (1743-1805), revitalizing his Watchmaker argument for God’s existence.

In my view, many examples of molecular-level biomachinery stand as strict analogs to human-made machinery in terms of architecture, operation, and assembly. The biomachines found in the cell’s interior reveal a diversity of form and function that mirrors the diversity of designs produced by human engineers. The one-to-one relationship between the parts of man-made machines and the molecular components of biomachines is startling (e.g., the flagellum’s hook). I believe Paley’s case continues to gain strength as biochemists continue to discover new examples of biomolecular machines.

The Skeptics’ Challenge

Despite the powerful analogy that exists between machines produced by human designers and biomolecular machines, many skeptics continue to challenge the revitalized watchmaker argument on logical grounds by arguing in the same vein as David Hume.1 These skeptics assert that significant and fundamental differences exist between biomachines and human creations.

In a recent interaction on Twitter, a skeptic raised just such an objection. Here is what he wrote:

“Do [objects and machines designed by humans] replicate with heritable variation? Bad analogy, category mistake. Same one Paley made with his watch on the heath centuries ago.”

In other words, biological systems replicate, whereas devices and artefacts made by human beings don’t. This difference is fundamental. Such a dissimilarity is so significant that it undermines the analogy between biological systems (in general) and biomolecular machines (specifically) and human designs, invalidating the conclusion that life must stem from a Mind.

This is not the first time I have encountered this objection. Still, I don’t find it compelling because it fails to take into account manmade machines that do, indeed, replicate.

Von Neumann’s Universal Self-Constructor

In the 1940s, mathematician, physicist, and computer scientist John von Neumann (1903–1957) designed a hypothetical machine called a universal constructor. This machine is a conceptual apparatus that can take materials from the environment and build any machine, including itself. The universal constructor requires instructions to build the desired machines and to build itself. It also requires a supervisory system that can switch back and forth between using the instructions to build other machines and copying the instructions prior to the replication of the universal constructor.

Von Neumann’s universal constructor is a conceptual apparatus, but today researchers are actively trying to design and build self-replicating machines.2 Much work needs to be done before self-replicating machines are a reality. Nevertheless, one day machines will be able to reproduce, making copies of themselves. To put it another way, reproduction isn’t necessarily a quality that distinguishes machines from biological systems.

It is interesting to me that a description of von Neumann’s universal constructor bears remarkable similarity to a description of a cell. In fact, in the context of the origin-of-life problem, astrobiologists Paul Davies and Sara Imari Walker noted the analogy between the cell’s information systems and von Neumann’s universal constructor.3 Davies and Walker think that this analogy is key to solving the origin-of-life problem. I would agree. However, Davies and Walker support an evolutionary origin of life, whereas I maintain that the analogy between cells and von Neumann’s universal constructor adds vigor to the revitalized Watchmaker argument and, in turn, the scientific case for a Creator.

In other words, the reproduction objection to the Watchmaker argument has little going for it. Self-replication is not the basis for viewing biomolecular machines as fundamentally dissimilar to machines created by human designers. Instead, self-replication stands as one more machine-like attribute of biochemical systems. It also highlights the sophistication of biological systems compared to systems produced by human designers. We are a far distance away from creating machines that are as sophisticated as the machines found inside the cell. Nevertheless, as we continue to move in that direction, I think the case for a Creator will become even more compelling.

Who knows? With insights such as these maybe one day we will return to the good old days of biology, when teleology was paramount.

Resources

Biomolecular Machines and the Watchmaker Argument

Responding to Challenges to the Watchmaker Argument

Endnotes
  1. “Whenever you depart, in the least, from the similarity of the cases, you diminish proportionably the evidence; and may at last bring it to a very weak analogy, which is confessedly liable to error and uncertainty.” David Hume, “Dialogues Concerning Natural Religion,” in Classics of Western Philosophy, 3rd ed., ed. Steven M. Cahn, (1779; repr., Indianapolis: Hackett, 1990), 880.
  2. For example, Daniel Mange et al., “Von Neumann Revisited: A Turing Machine with Self-Repair and Self-Reproduction Properties,” Robotics and Autonomous Systems 22 (1997): 35-58, https://doi.org/10.1016/S0921-8890(97)00015-8; Jean-Yves Perrier, Moshe Sipper, and Jacques Zahnd, “Toward a Viable, Self-Reproducing Universal Computer,” Physica D: Nonlinear Phenomena
     97, no. 4 (October 15, 1996): 335–52, https://doi.org/10.1016/0167-2789(96)00091-7; Umberto Pesavento, “An Implementation of von Neumann’s Self-Reproducing Machine,” Artificial Life 2, no. 4 (Summer 1995): 337–54, https://doi.org/10.1162/artl.1995.2.4.337.
  3. Sara Imari Walker and Paul C. W. Davies, “The Algorithmic Origins of Life,” Journal of the Royal Society Interface 10 (2013), doi:10.1098/rsif.2012.0869.

Reprinted with permission by the author

Original article at:

https://reasons.org/explore/blogs/the-cells-design

Self-Assembly of Protein Machines: Evidence for Evolution or Creation?

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BY FAZALE RANA – APRIL 17, 2019

I finally upgraded my iPhone a few weeks ago from a 5s to an 8 Plus. I had little choice. The battery on my cell phone would no longer hold a charge.

I’d put off getting a new one for as long as possible. It just didn’t make sense to spend money chasing the latest and greatest technology when current cell phone technology worked perfectly fine for me. Apart from the battery life and a less-than-ideal camera, I was happy with my iPhone 5s. Now I am really glad I made the switch.

Then, the other day I caught myself wistfully eyeing the iPhone X. And, today, I learned that Apple is preparing the release of the iPhone 11 (or XI or XT). Where will Apple’s technology upgrades take us next? I can’t wait to find out.

Have I become a technology junkie?

It is remarkable how quickly cell phone technology advances. It is also remarkable how alluring new technology can be. The next thing you know, Apple will release an iPhone that will assemble itself when it comes out of the box. . . . Probably not.

But, if the work of engineers at MIT ever reaches fruition, it is possible that smartphone manufacturers one day just might rely on a self-assembly process to produce cell phones.

A Self-Assembling Cell Phone

The Self-Assembly Lab at MIT has developed a pilot process to manufacture cell phones by self-assembly.

To do this, they designed their cell phone to consist of six parts that fit together in a lock-in-key manner. By placing the cell phone pieces into a tumbler that turns at the just-right speed, the pieces automatically combine with one another, bit by bit, until the cell phone is assembled.

Few errors occur during the assembly process. Only pieces designed to fit together combine with one another because of the lock-in-key fabrication.

Self-Assembly and the Case for a Creator

It is quite likely that the work of MIT’s Self-Assembly Lab (and other labs like it) will one day revolutionize manufacturing—not just for iPhones, but for other types of products as well.

As alluring as this new technology might be, I am more intrigued by its implications for the creation-evolution controversy. What do self-assembly processes have to do with the creation-evolution debate? More than we might realize.

I believe self-assembly processes strengthen the watchmaker argument for God’s existence (and role in the origin of life). Namely, this cutting-edge technology makes it possible to respond to a common objection leveled against this design argument.

To understand why this engineering breakthrough is so important for the Watchmaker argument, a little background is necessary.

The Watchmaker Argument

Anglican natural theologian William Paley (1743–1805) posited the Watchmaker argument in the eighteenth century. It went on to become one of the best-known arguments for God’s existence. The argument hinges on the comparison Paley made between a watch and a rock. He argued that a rock’s existence can be explained by the outworking of natural processes—not so for a watch.

The characteristics of a watch—specifically the complex interaction of its precision parts for the purpose of telling time—implied the work of an intelligent designer. Employing an analogy, Paley asserted that just as a watch requires a watchmaker, so too, life requires a Creator. Paley noted that biological systems display a wide range of features characterized by the precise interplay of complex parts designed to interact for specific purposes. In other words, biological systems have much more in common with a watch than a rock. This similarity being the case, it logically follows that life must stem from the work of a Divine Watchmaker.

Biochemistry and the Watchmaker Argument

As I discuss in my book The Cell’s Design, advances in biochemistry have reinvigorated the Watchmaker argument. The hallmark features of biochemical systems are precisely the same properties displayed in objects, devices, and systems designed and crafted by humans.

Cells contain protein complexes that are structured to operate as biomolecular motors and machines. Some molecular-level biomachines are strict analogs to machinery produced by human designers. In fact, in many instances, a one-to-one relationship exists between the parts of manufactured machines and the molecular components of biomachines. (A few examples of these biomolecular machines are discussed in the articles listed in the Resources section.)

We know that machines originate in human minds that comprehend and then implement designs. So, when scientists discover example after example of biomolecular machines inside the cell with an eerie and startling similarity to the machines we produce, it makes sense to conclude that these machines and, hence, life, must also have originated in a Mind.

A Skeptic’s Challenge

As you might imagine, skeptics have leveled objections against the Watchmaker argument since its introduction in the 1700s. Today, when skeptics criticize the latest version of the Watchmaker argument (based on biochemical designs), the influence of Scottish skeptic David Hume (1711–1776) can be seen and felt.

In his 1779 work Dialogues Concerning Natural Religion, Hume presented several criticisms of design arguments. The foremost centered on the nature of analogical reasoning. Hume argued that the conclusions resulting from analogical reasoning are only sound when the things compared are highly similar to each other. The more similar, the stronger the conclusion. The less similar, the weaker the conclusion.

Hume dismissed the original version of the Watchmaker argument by maintaining that organisms and watches are nothing alike. They are too dissimilar for a good analogy. In other words, what is true for a watch is not necessarily true for an organism and, therefore, it doesn’t follow that organisms require a Divine Watchmaker, just because a watch does.

In effect, this is one of the chief reasons why some skeptics today dismiss the biochemical Watchmaker argument. For example, philosopher Massimo Pigliucci has insisted that Paley’sanalogy is purely metaphorical and does not reflect a true analogical relationship. He maintains that any similarity between biomolecular machines and human designs reflects merely illustrative analogies that life scientists use to communicate the structure and function of these protein complexes via familiar concepts and language. In other words, it is illegitimate to use the “analogies” between biomolecular machines and manufactured machines to make a case for a Creator.1

A Response Based on Insights from Nanotechnology

I have responded to this objection by pointing out that nanotechnologists have isolated biomolecular machines from the cell and incorporated these protein complexes into nanodevices and nanosystems for the explicit purpose of taking advantage of their machine-like properties. These transplanted biomachines power motion and movements in the devices, which otherwise would be impossible with current technology. In other words, nanotechnologists view these biomolecular systems as actual machines and utilize them as such. Their work demonstrates that biomolecular machines are literal, not metaphorical, machines. (See the Resources section for articles describing this work.)

Is Self-Assembly Evidence of Evolution or Design?

Another criticism—inspired by Hume—is that machines designed by humans don’t self-assemble, but biochemical machines do. Skeptics say this undermines the Watchmaker analogy. I have heard this criticism in the past, but it came up recently in a dialogue I had with a skeptic in a Facebook group.

I wrote that “What we discover when we work out the structure and function of protein complexes are features that are akin to an automobile engine, not an outcropping of rocks.”

A skeptic named Maurice responded: “Your analogy is false. Cars do not spontaneously self-assemble—in that case there is a prohibitive energy barrier. But hexagonal lava rocks can and do—there is no energy barrier to prohibit that from happening.”

Maurice argues that my analogy is a poor one because protein complexes in the cell self-assemble, whereas automobile engines can’t. For Maurice (and other skeptics), this distinction serves to make manufactured machines qualitatively different from biomolecular machines. On the other hand, hexagonal patterns in lava rocks give the appearance of design but are actually formed spontaneously. For skeptics like Maurice, this feature indicates that the design displayed by protein complexes in the cell is apparent, not true, design.

Maurice added: “Given that nature can make hexagonal lava blocks look ‘designed,’ it can certainly make other objects look ‘designed.’ Design is not a scientific term.”

Self-Assembly and the Watchmaker Argument

This is where the MIT engineers’ fascinating work comes into play.

Engineers continue to make significant progress toward developing self-assembly processes for manufacturing purposes. It very well could be that in the future a number of machines and devices will be designed to self-assemble. Based on the researchers’ work, it becomes evident that part of the strategy for designing machines that self-assemble centers on creating components that not only contribute to the machine’s function, but also precisely interact with the other components so that the machine assembles on its own.

The operative word here is designed. For machines to self-assemble they must be designed to self-assemble.

This requirement holds true for biochemical machines, too. The protein subunits that interact to form the biomolecular machines appear to be designed for self-assembly. Protein-protein binding sites on the surface of the subunits mediate this self-assembly process. These binding sites require high-precision interactions to ensure that the binding between subunits takes place with a high degree of accuracy—in the same way that the MIT engineers designed the cell phone pieces to precisely combine through lock-in-key interactions.

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Figure: ATP Synthase is a biomolecular motor that is literally an electrically powered rotary motor. This biomachine is assembled from protein subunits. Credit: Shutterstock

The level of design required to ensure that protein subunits interact precisely to form machine-like protein complexes is only beginning to come into full view.2 Biochemists who work in the area of protein design still don’t fully understand the biophysical mechanisms that dictate the assembly of protein subunits. And, while they can design proteins that will self-assemble, they struggle to replicate the complexity of the self-assembly process that routinely takes place inside the cell.

Thanks to advances in technology, biomolecular machines’ ability to self-assemble should no longer count against the Watchmaker argument. Instead, self-assembly becomes one more feature that strengthens Paley’s point.

The Watchmaker Prediction

Advances in self-assembly also satisfy the Watchmaker prediction, further strengthening the case for a Creator. In conjunction with my presentation of the revitalized Watchmaker argument in The Cell’s Design, I proposed the Watchmaker prediction. I contend that many of the cell’s molecular systems currently go unrecognized as analogs to human designs because the corresponding technology has yet to be developed.

The possibility that advances in human technology will ultimately mirror the molecular technology that already exists as an integral part of biochemical systems leads to the Watchmaker prediction. As human designers develop new technologies, examples of these technologies, though previously unrecognized, will become evident in the operation of the cell’s molecular systems. In other words, if the Watchmaker argument truly serves as evidence for a Creator’s existence, then it is reasonable to expect that life’s biochemical machinery anticipates human technological advances.

In effect, the developments in self-assembly technology and its prospective use in future manufacturing operations fulfill the Watchmaker prediction. Along these lines, it’s even more provocative to think that cellular self-assembly processes are providing insight to engineers who are working to develop similar technology.

Maybe I am a technology junkie, after all. I find it remarkable that as we develop new technologies we discover that they already exist in the cell, and because they do the Watchmaker argument becomes more and more compelling.

Can you hear me now?

Resources

The Biochemical Watchmaker Argument

Challenges to the Biochemical Watchmaker Argument

Endnotes
  1. Massimo Pigliucci and Maarten Boudry, “Why Machine-Information Metaphors are Bad for Science and Science Education,” Science and Education 20, no. 5–6 (May 2011): 453–71; doi:10.1007/s11191-010-9267-6.
  2. For example, see Christoffer H. Norn and Ingemar André, “Computational Design of Protein Self-Assembly,” Current Opinion in Structural Biology 39 (August 2016): 39–45, doi:10.1016/j.sbi.2016.04.002.

Reprinted with permission by the author
Original article at:
https://www.reasons.org/explore/blogs/the-cells-design/read/the-cells-design/2019/04/17/self-assembly-of-protein-machines-evidence-for-evolution-or-creation

The Optimal Design of the Genetic Code

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BY FAZALE RANA – OCTOBER 3, 2018

Were there no example in the world of contrivance except that of the eye, it would be alone sufficient to support the conclusion which we draw from it, as to the necessity of an intelligent Creator.

–William Paley, Natural Theology

In his classic work, Natural Theology, William Paley surveyed a range of biological systems, highlighting their similarities to human-made designs. Paley noticed that human designs typically consist of various components that interact in a precise way to accomplish a purpose. According to Paley, human designs are contrivances—things produced with skill and cleverness—and they come about via the work of human agents. They come about by the work of intelligent designers. And because biological systems are contrivances, they, too, must come about via the work of a Creator.

For Paley, the pervasiveness of biological contrivances made the case for a Creator compelling. But he was especially struck by the vertebrate eye. For Paley, if the only example of a biological contrivance available to us was the eye, its sophisticated design and elegant complexity alone justify the “necessity of an intelligent creator” to explain its origin.

As a biochemist, I am impressed with the elegant designs of biochemical systems. The sophistication and ingenuity of these designs convinced me as a graduate student that life must stem from the work of a Mind. In my book The Cell’s Design, I follow in Paley’s footsteps by highlighting the eerie similarity between human designs and biochemical systems—a similarity I describe as an intelligent design pattern. Because biochemical systems conform to the intelligent design pattern, they must be the work of a Creator.

As with Paley, I view the pervasiveness of the intelligent design pattern in biochemical systems as critical to making the case for a Creator. Yet, in particular, I am struck by the design of a single biochemical system: namely, the genetic code. On the basis of the structure of the genetic code alone, I think one is justified to conclude that life stems from the work of a Divine Mind. The latest work by a team of German biochemists on the genetic code’s design convinces me all the more that the genetic code is the product of a Creator’s handiwork.1

To understand the significance of this study and the code’s elegant design, a short primer on molecular biology is in order. (For those who have a background in biology, just skip ahead to The Optimal Genetic Code.)

Proteins

The “workhorse” molecules of life, proteins take part in essentially every cellular and extracellular structure and activity. Proteins are chain-like molecules folded into precise three-dimensional structures. Often, the protein’s three-dimensional architecture determines the way it interacts with other proteins to form a functional complex.

Proteins form when the cellular machinery links together (in a head-to-tail fashion) smaller subunit molecules called amino acids. To a first approximation, the cell employs 20 different amino acids to make proteins. The amino acids that make up proteins possess a variety of chemical and physical properties.

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Figure 1: The Amino Acids. Image credit: Shutterstock

Each specific amino acid sequence imparts the protein with a unique chemical and physical profile along the length of its chain. The chemical and physical profile determines how the protein folds and, therefore, its function. Because structure determines the function of a protein, the amino acid sequence is key to dictating the type of work a protein performs for the cell.

DNA

The cell’s machinery uses the information harbored in the DNA molecule to make proteins. Like these biomolecules, DNA consists of chain-like structures known as polynucleotides. Two polynucleotide chains align in an antiparallel fashion to form a DNA molecule. (The two strands are arranged parallel to one another with the starting point of one strand located next to the ending point of the other strand, and vice versa.) The paired polynucleotide chains twist around each other to form the well-known DNA double helix. The cell’s machinery forms polynucleotide chains by linking together four different subunit molecules called nucleotides. The four nucleotides used to build DNA chains are adenosine, guanosine, cytidine, and thymidine, familiarly known as A, G, C, and T, respectively.

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Figure 2: The Structure of DNA. Image credit: Shutterstock

As noted, DNA stores the information necessary to make all the proteins used by the cell. The sequence of nucleotides in the DNA strands specifies the sequence of amino acids in protein chains. Scientists refer to the amino-acid-coding nucleotide sequence that is used to construct proteins along the DNA strand as a gene.

The Genetic Code

A one-to-one relationship cannot exist between the 4 different nucleotides of DNA and the 20 different amino acids used to assemble polypeptides. The cell addresses this mismatch by using a code comprised of groupings of three nucleotides to specify the 20 different amino acids.

The cell uses a set of rules to relate these nucleotide triplet sequences to the 20 amino acids making up proteins. Molecular biologists refer to this set of rules as the genetic code. The nucleotide triplets, or “codons” as they are called, represent the fundamental communication units of the genetic code, which is essentially universal among all living organisms.

Sixty-four codons make up the genetic code. Because the code only needs to encode 20 amino acids, some of the codons are redundant. That is, different codons code for the same amino acid. In fact, up to six different codons specify some amino acids. Others are specified by only one codon.

Interestingly, some codons, called stop codons or nonsense codons, code no amino acids. (For example, the codon UGA is a stop codon.) These codons always occur at the end of the gene, informing the cell where the protein chain ends.

Some coding triplets, called start codons, play a dual role in the genetic code. These codons not only encode amino acids, but also “tell” the cell where a protein chain begins. For example, the codon GUG encodes the amino acid valine and also specifies the starting point of the proteins.

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Figure 3: The Genetic Code. Image credit: Shutterstock

The Optimal Genetic Code

Based on visual inspection of the genetic code, biochemists had long suspected that the coding assignments weren’t haphazard—a frozen accident. Instead it looked to them like a rationale undergirds the genetic code’s architecture. This intuition was confirmed in the early 1990s. As I describe in The Cell’s Design, at that time, scientists from the University of Bath (UK) and from Princeton University quantified the error-minimization capacity of the genetic code. Their initial work indicated that the naturally occurring genetic code withstands the potentially harmful effects of substitution mutations better than all but 0.02 percent (1 out of 5,000) of randomly generated genetic codes with codon assignments different from the universal genetic code.2

Subsequent analysis performed later that decade incorporated additional factors. For example, some types of substitution mutations (called transitions) occur more frequently in nature than others (called transversions). As a case in point, an A-to-G substitution occurs more frequently than does either an A-to-C or an A-to-T mutation. When researchers included this factor into their analysis, they discovered that the naturally occurring genetic code performed better than one million randomly generated genetic codes. In a separate study, they also found that the genetic code in nature resides near the global optimum for all possible genetic codes with respect to its error-minimization capacity.3

It could be argued that the genetic code’s error-minimization properties are more dramatic than these results indicate. When researchers calculated the error-minimization capacity of one million randomly generated genetic codes, they discovered that the error-minimization values formed a distribution where the naturally occurring genetic code’s capacity occurred outside the distribution. Researchers estimate the existence of 1018 (a quintillion) possible genetic codes possessing the same type and degree of redundancy as the universal genetic code. Nearly all of these codes fall within the error-minimization distribution. This finding means that of 1018 possible genetic codes, only a few have an error-minimization capacity that approaches the code found universally in nature.

Frameshift Mutations

Recently, researchers from Germany wondered if this same type of optimization applies to frameshift mutations. Biochemists have discovered that these mutations are much more devastating than substitution mutations. Frameshift mutations result when nucleotides are inserted into or deleted from the DNA sequence of the gene. If the number of inserted/deleted nucleotides is not divisible by three, the added or deleted nucleotides cause a shift in the gene’s reading frame—altering the codon groupings. Frameshift mutations change all the original codons to new codons at the site of the insertion/deletion and onward to the end of the gene.

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Figure 4: Types of Mutations. Image credit: Shutterstock

The Genetic Code Is Optimized to Withstand Frameshift Mutations

Like the researchers from the University of Bath, the German team generated 1 million random genetic codes with the same type and degree of redundancy as the genetic code found in nature. They discovered that the code found in nature is better optimized to withstand errors that result from frameshift mutations (involving either the insertion or deletion of 1 or 2 nucleotides) than most of the random genetic codes they tested.

The Genetic Code Is Optimized to Harbor Multiple Overlapping Codes

The optimization doesn’t end there. In addition to the genetic code, genes harbor other overlapping codes that independently direct the binding of histone proteins and transcription factors to DNA and dictate processes like messenger RNA folding and splicing. In 2007, researchers from Israel discovered that the genetic code is also optimized to harbor overlapping codes.4

The Genetic Code and the Case for a Creator

In The Cell’s Design, I point out that common experience teaches us that codes come from minds. By analogy, the mere existence of the genetic code suggests that biochemical systems come from a Mind. This conclusion gains considerable support based on the exquisite optimization of the genetic code to withstand errors that arise from both substitution and frameshift mutations, along with its optimal capacity to harbor multiple overlapping codes.

The triple optimization of the genetic code arises from its redundancy and the specific codon assignments. Over 1018 possible genetic codes exist and any one of them could have been “selected” for the code in nature. Yet, the “chosen” code displays extreme optimization—a hallmark feature of designed systems. As the evidence continues to mount, it becomes more and more evident that the genetic code displays an eerie perfection.5

An elegant contrivance such as the genetic code—which resides at the heart of biochemical systems and defines the information content in the cell—is truly one in a million when it comes to reasons to believe.

Resources

Endnotes

  1. Regine Geyer and Amir Madany Mamlouk, “On the Efficiency of the Genetic Code after Frameshift Mutations,” PeerJ 6 (2018): e4825, doi:10.7717/peerj.4825.
  2. David Haig and Laurence D. Hurst, “A Quantitative Measure of Error Minimization in the Genetic Code,” Journal of Molecular Evolution33 (1991): 412–17, doi:1007/BF02103132.
  3. Gretchen Vogel, “Tracking the History of the Genetic Code,” Science281 (1998): 329–31, doi:1126/science.281.5375.329; Stephen J. Freeland and Laurence D. Hurst, “The Genetic Code Is One in a Million,” Journal of Molecular Evolution 47 (1998): 238–48, doi:10.1007/PL00006381.; Stephen J. Freeland et al., “Early Fixation of an Optimal Genetic Code,” Molecular Biology and Evolution 17 (2000): 511–18, doi:10.1093/oxfordjournals.molbev.a026331.
  4. Shalev Itzkovitz and Uri Alon, “The Genetic Code Is Nearly Optimal for Allowing Additional Information within Protein-Coding Sequences,” Genome Research(2007): advanced online, doi:10.1101/gr.5987307.
  5. In The Cell’s Design, I explain why the genetic code cannot emerge through evolutionary processes, reinforcing the conclusion that the cell’s information systems—and hence, life—must stem from the handiwork of a Creator.
Reprinted with permission by the author
Original article at:
https://www.reasons.org/explore/blogs/the-cells-design/read/the-cells-design/2018/10/03/the-optimal-design-of-the-genetic-code

The Multiplexed Design of Neurons

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BY FAZALE RANA – AUGUST 22, 2018

In 1910, Major General George Owen Squier developed a technique to increase the efficiency of data transmission along telephone lines that is still used today in telecommunications and computer networks. This technique, called multiplexing, allows multiple signals to be combined and transmitted along a single cable, making it possible to share a scarce resource (available phone lines, in Squier’s day).

Today, there are a number of ways to carry out multiplexing. One of them is called time-division multiplexing. While other forms of multiplexing can be used for analog data, this technique can only be applied to digital data. Data is transmitted as a collection of bits along a single channel separated by a time interval that allows the data groups to be directed to the appropriate receiver.

Researchers from Duke University have discovered that neurons employ time-division multiplexing to transmit multiple electrical signals along a single axon.1 The remarkable similarity between data transmission techniques used by neurons and telecommunication systems and computer networks is provocative. It can also be marshaled to add support to the revitalized Watchmaker argument for God’s existence and role in the origin and design of life.

A brief primer on neurons will help us better appreciate the work of the Duke research team.

Neurons

The primary component of the nervous system (the brain, spinal cord, and the peripheral system of nerves), neurons are electrically excitable cells that rely on electrochemical processes to receive and send electrical signals. By connecting to each other through specialized structures called synapses, neurons form pathways that transmit information throughout the nervous system.

Neurons consist of the soma or cell body, along with several outward extending projections called dendrites and axons.

multiplexed-design-of-neuronsImage credit: Wikipedia

Dendrites are “tree-like” projections that extend from the soma into the synaptic space. Receptors on the surface of dendrites bind neurotransmitters deposited by adjacent neurons in the synapse. These binding events trigger an electrical signal that travels along the length of the dendrites to the soma. However, axons conduct electrical impulses away from the soma toward the synapse, where this signal triggers the release of neurotransmitters into the extracellular medium, initiating electrical activity in the dendrites of adjacent neurons.

Sensory Neurons

In the world around us, many things happen at the same time. And we need to be aware of all of these events. Sensory neurons react to stimuli, communicating information about the environment to our brains. Many different types of sensory neurons exist, making possible our sense of sight, smell, taste, hearing, touch, and temperature. These sensory neurons have to be broadly tuned and may have to respond to more than one environmental stimulus at the same time. An example of this scenario would be carrying on a conversation with a friend at an outdoor café while the sounds of the city surround us.

The Duke University researchers wanted to understand the mechanism neurons employ when they transmit information about two or more environmental stimuli at the same time. To accomplish this, the scientists trained two macaques (monkeys) to look in the direction of two distinct sounds produced at two different locations in the room. After achieving this step, the researchers planted electrodes into the inferior colliculus of the monkeys’ brains and used these electrodes to record the activity of single neurons as the monkeys responded to auditory stimuli. The researchers discovered that each sound produced a unique firing rate along single neurons and that when the two sounds were presented at the same time, the neuron transmitting the electrical signals alternated back and forth between the two firing rates. In other words, the neurons employed time-division multiplexing to transmit the two signals.

Neuron Multiplexing and the Case for Creation

The capacity of neurons to multiplex signals generated by environmental stimuli exemplifies the elegance and sophistication of biological designs. And it is discoveries such as these that compel me to believe that life must stem from the work of a Creator.

But the case for a Creator extends beyond the intuition of design. Discoveries like this one breathe new life into the Watchmaker argument.

British natural theologian William Paley (1743–1805) advanced this argument by pointing out that the characteristics of a watch—with the complex interaction of its precision parts for the purpose of telling time—implied the work of an intelligent designer. Paley asserted by analogy that just as a watch requires a watchmaker, so too, does life require a Creator, since organisms display a wide range of features characterized by the precise interplay of complex parts for specific purposes.

Over the centuries, skeptics have maligned this argument by claiming that biological systems only bear a superficial similarity to human designs. That is, the analogy between human designs and biological systems is weak and, therefore, undermines the conclusion that a Divine Watchmaker exits. But, as I discuss in The Cell’s Design, the discovery of molecular motors, biochemical watches, and DNA computers—biochemical complexes with machine-like characteristics—energizes the argument. These systems are identical to the highly sophisticated machines and devices we build as human designers. In fact, these biochemical systems have been directly incorporated into nanotechnologies. And, we recognize that motors and computers, not to mention watches, come from minds. So, why wouldn’t we conclude that these biochemical systems come from a mind, as well?

Analogies between human machines and biological systems are not confined to biochemical systems. We see them at the biological level as well, as the latest work by the research team from Duke University illustrates.

It is fascinating to me that as we learn more about living systems, whether at the molecular scale, the cellular level, or the systems stage, we discover more and more instances in which biological systems bear eerie similarities to human designs. This learning strengthens the Watchmaker argument and the case for a Creator.

Resources

Endnotes

  1. Valeria C. Caruso et al., “Single Neurons May Encode Simultaneous Stimuli by Switching between Activity Patterns,” Nature Communications 9 (2018): 2715, doi:10.1038/s41467-018-05121-8.
Reprinted with permission by the author
Original article at:
https://www.reasons.org/explore/blogs/the-cells-design/read/the-cells-design/2018/08/22/the-multiplexed-design-of-neurons