Can Dinosaurs Be Resurrected from Extinction?

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By Fazale Rana – September 25, 2019

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.

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Figure 1: Dinosaur Foot Structure. Image credit: Shutterstock

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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).

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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

Shared Biological Designs and the Creation Model

Endnotes
  1. Bhart-Anjan S. Bhullar et al., “A Molecular Mechanism for the Origin of a Key Evolutionary Innovation, the Bird Beak and Palate, Revealed by an Integrative Approach to Major Transitions in Vertebrate History,” Evolution 69, no. 7 (2015): 1665–77, doi:10.1111/evo.12684.
  2. João Francisco Botelho et al., “Skeletal Plasticity in Response to Embryonic Muscular Activity Underlies the Development and Evolution of the Perching Digit of Birds,” Scientific Reports 5 (May 14, 2015): 9840, doi:10.1038/srep09840.
  3. João Francisco Botelho et al., “Molecular Developments of Fibular Reduction in Birds and Its Evolution from Dinosaurs,” Evolution 70, no. 3 (March, 2016): 543–54, doi:10.1111/evo.12882.

Reprinted with permission by the author

Original article at:
https://www.reasons.org/explore/blogs/the-cells-design/read/the-cells-design/2018/11/21/vocal-signals-smile-on-the-case-for-human-exceptionalism

Soft Tissue Preservation Mechanism Stabilizes the Case for Earth’s Antiquity

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BY FAZALE RANA – DECEMBER 19, 2018

One of the highlights of the year at Reasons to Believe (well, it’s a highlight for some of us, anyway) is the white elephant gift exchange at our staff Christmas party. It is great fun to laugh together as a staff as we take turns unwrapping gifts—some cheesy, some useless, and others highly prized—and then “stealing” from one another those two or three gifts that everyone seems to want.

Over the years, I have learned a few lessons about choosing a white elephant gift to unwrap. Avoid large gifts. If the gift is a dud, large items are more difficult to find a use for than small ones. Also, more often than not, the most beautifully wrapped gifts turn out to be the biggest letdowns of all.

Giving and receiving gifts isn’t just limited to Christmas. People exchange all types of gifts with one another for all sorts of reasons.

Gifting is even part of the scientific enterprise—with the gifts taking on the form of scientific discoveries and advances. Many times, discoveries lead to new beneficial insights and technologies—gifts for humanity. Other times, these breakthroughs are gifts for scientists, signaling a new way to approach a scientific problem or opening up new vistas of investigation.

Soft Tissue Remnants Preserved in Fossils

One such gift was given to the scientific community over a decade ago by Mary Schweitzer, a paleontologist at North Carolina State University. Schweitzer and her team of collaborators recovered flexible, hollow, and transparent blood vessels from the remains of a T. rex specimen after removing the mineral component of the fossil.1 These blood vessels harbored microstructures with a cell-like morphology (form and structure) that she and her collaborators interpreted to be the remnants of red blood cells. This work showed conclusively that soft tissue materials could be preserved in fossil remains.

Though unexpected, the discovery was a landmark achievement for paleontology. Since Schweitzer’s discovery, paleontologists have unearthed the remnants of all sorts of soft tissue materials from fossils representing a wide range of organisms. (For a catalog of some of these finds, see my book Dinosaur Blood and the Age of the Earth.)

With access to soft tissue materials in fossils, paleontologists have a new window into the biology of Earth’s ancient life.

The Scientific Case for a Young Earth

Some Christians also saw Schweitzer’s discovery as a gift. But for them the value of this scientific present wasn’t the insight it provides about past life on Earth. Instead, they viewed this discovery (and others like it) as evidence that the earth must be no more than a few thousand years old. From a young-earth creationist (YEC) perspective, the survival of soft tissue materials in fossils indicates that these remains can’t be millions of years old. As a case in point, at the time Schweitzer reported her findings, John Morris, a young-earth proponent from the Institute for Creation Research, wrote:

Indeed, it is hard to imagine how soft tissue could have lasted even 5,000 years or so since the Flood of Noah’s day when creationists propose the dinosaur was buried. Such a thing could hardly happen today, for soft tissue decays rather quickly under any condition.2

In other words, from a YEC perspective, it is impossible for fossils to contain soft tissue remnants and be millions of years old. Soft tissues shouldn’t survive that long; they should readily degrade in a few thousand years. From a YEC view, soft tissue discoveries challenge the reliability of radiometric dating methods used to determine the fossils’ ages and, consequently, Earth’s antiquity. Furthermore, these breakthrough discoveries provide compelling scientific evidence for a young earth and support the idea that the fossil record results from a recent global (worldwide) flood.

Admittedly, on the surface the argument carries some weight. At first glance, it is hard to envision how soft tissue materials could survive for vast periods of time, given the wide range of mechanisms that drive the degradation of biological materials.

Preservation of Soft Tissues in Fossil Remains

Despite this first impression, over the last decade or so paleontologists have identified a number of mechanisms that can delay the degradation of soft tissues long enough for them to become entombed within a mineral shell. When this entombment happens, the soft tissue materials escape further degradation (for the most part). In other words, it is a race against time. Can mineral entombment take place before the soft tissue materials fully decompose? If so, then soft tissue remnants can survive for hundreds of millions of years. And any chemical or physical process that can delay the degradation will contribute to soft tissue survival by giving the entombment process time to take place.

In Dinosaur Blood and the Age of the Earth, I describe several mechanisms that likely promote soft tissue survival. Since the book’s publication (2016), researchers have deepened their understanding of the processes that make it possible for soft tissues to survive. The recent work of an international team of collaborators headed by researchers from Yale University provides an example of this growing insight.3

These researchers discovered that the deposition environment during the fossilization process plays a significant role in soft tissue preservation, and they have identified the chemical reactions that contribute to this preservation. The team examined 24 specimens of biomineralized vertebrate tissues ranging in age from modern to the Late Jurassic (approximately 163–145 million years ago) time frame. These specimens were taken from both chemically oxidative and reductive environments.

After demineralizing the samples, the researchers discovered that all modern specimens yielded soft tissues. However, demineralization only yielded soft tissues for fossils formed under oxidative conditions. Fossils formed under reductive conditions failed to yield any soft tissue material, whatsoever. The soft tissues from the oxidative settings (which included extracellular matrices, cell remnants, blood vessel remnants, and nerve materials) were stained brown. Researchers noted that the brown color of the soft tissue materials increased in intensity as a function of the fossil’s age, with older specimens displaying greater browning than younger specimens.

The team was able to reproduce this brown color in soft tissues taken from modern-day specimens by heating the samples and exposing them to air. This process converted the soft tissues from translucent white to brown in appearance.

Using Raman spectroscopy, the researchers detected spectral signatures for proteins and N-heterocycle pyridine rings in the soft tissue materials. They believe that the N-heterocycle pyridine rings arise from the formation of advanced glycoxidation end-products (AGEs) and advanced lipoxidation end-products (ALEs). AGEs and ALEs are the by-products of the reactions that take place between proteins and sugars (AGEs) and proteins and lipids or fats (ALEs). (As an aside, AGEs and ALEs form when foods are cooked, and they occur at high levels when food is burnt, giving overly cooked foods their brownish color.) The researchers noted that spectral features for N-heterocycle pyridine rings become more prominent for soft tissues isolated from older fossil specimens, with the spectral features for the proteins becoming less pronounced.

AGEs and ALEs are heavily cross-linked compounds. This chemical property makes them extremely difficult to break down once they form. In other words, the formation of AGEs and ALEs in soft tissue remnants delays their decomposition long enough for mineral entombment to take place.

Iron from the environment or released from red blood cells promotes the formation of AGEs and ALEs. So do alkaline conditions.

In addition to stabilizing soft tissues from degradation because of the cross-links, AGEs and ALEs protect adjacent proteins from breakdown because of their hydrophobic (water repellent) nature. Water promotes soft tissue breakdown through a chemical process called hydrolysis. But because AGEs and ALEs are hydrophobic, they inhibit the hydrolytic reactions that would otherwise break down proteins that escape glycoxidation and lipoxidation reactions.

Finally, AGEs and ALEs are also resistant to microbial attack, further adding to the stability of the soft tissue materials. In other words, soft tissue materials recovered from fossil specimens are not the original, intact material, because they have undergone extensive chemical alteration. As it turns out, this alteration stabilized the soft tissue remnants long enough for mineral entombment to occur.

In short, this research team has made significant strides toward understanding the process by which soft tissue materials become preserved in fossil remains. The recovery of soft tissue materials from the ancient fossil remains makes perfect sense within an old-earth framework. These insights also undermine what many people believe to be one of the most compelling scientific arguments for a young earth.

Why Does It Matter?

In my experience, many skeptics and seekers alike reject Christian truth claims because of the misperception that Genesis 1 teaches that the earth is only 6,000 years old. This misperception becomes reinforced by vocal (and well-meaning) YECs who not only claim the only valid interpretation of Genesis 1 is the calendar-day view, but also maintain that ample scientific evidence—such as the recovery of soft tissue remnants in fossils—exists for a young earth.

Yet, as the latest work headed by scientists from Yale University demonstrates, soft tissue remnants associated with fossils find a ready explanation from an old-earth standpoint. It has been a gift to science that advances understanding of a sophisticated process.

Unfortunately, for YECs the fossil-associated soft tissues have turned out to be little more than a bad white elephant gift.

Resources:

Endnotes
  1. Mary H. Schweitzer et al., “Soft-Tissue Vessels and Cellular Preservation in Tyrannosaurus rex,” Science 307 (March 25, 2005): 1952–55, doi:10.1126/science.1108397.
  2. John D. Morris, “Dinosaur Soft Parts,” Acts & Facts (June 1, 2005), icr.org/article/2032/.
  3. Jasmina Wiemann et al., “Fossilization Transforms Vertebrate Hard Tissue Proteins into N-Heterocyclic Polymers,” Nature Communications 9 (November 9, 2018): 4741, doi:10.1038/s41467-018-07013-3.
Reprinted with permission by the author
Original article at:
https://www.reasons.org/explore/blogs/the-cells-design/read/the-cells-design/2018/12/19/soft-tissue-preservation-mechanism-stabilizes-the-case-for-earth-s-antiquity

Does Radiocarbon Dating Prove a Young Earth? A Response to Vernon R. Cupps

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BY FAZALE RANA – APRIL 19, 2017

In my experience, one of the most persuasive scientific claims for a young Earth is the detection of carbon-14 in geological samples such as coal and fossilized dinosaur remains.1According to young-earth creationists (YECs), if the coal samples and fossils are truly millions of years old (as the scientific community claims), then there shouldn’t be any trace of carbon-14 in these samples. Why? It’s because the half-life of carbon-14 is about 5,700 years, meaning that all the detectable carbon-14 should have disappeared from the samples long before they reach even 100,000 years of age.

In Dinosaur Blood and the Age of the Earth, I respond to this young-earth argument, suggesting three mechanisms that can account for carbon-14 in fossil remains (and by extension, in geological materials) from an old-earth perspective.

When YECs detect carbon-14, they find it at low levels, corresponding to age dates older than 30,000 years (not 3,000 to 6,000 years old, as their model predicts, by the way). These low levels make it reasonable to think that some of the carbon-14 signal comes from contamination of the sample by, say, microorganisms picked up from the environment.

These low levels also make it conceivable that some of the detected carbon-14 is due to a ubiquitous carbon-14 background. Cosmic rays are continuously producing radiocarbon from nitrogen-14. Because of this nonstop production, carbon-14 is everywhere and will show up at extremely low levels in any measurement that is made, even if it isn’t present in the actual sample.

It is also possible that some of the carbon-14 in the fossil and coal samples arises from the in situ conversion of nitrogen-14 to carbon-14 driven by the decay of radioactive elements in the environment. Because fossils and coal derive from once-living organisms, there will be plenty of nitrogen-14 contained in these specimens. For example, environmental uranium and thorium would readily infuse into the interiors of fossils, and as these elements decay, the high energy they release will convert nitrogen-14 to carbon-14.

Employing a “back-of-the-envelope” flux analysis, Vernon Cupps—a YEC affiliated with the Institute of Creation Research—has challenged my assessment, concluding that neither (1) the production of carbon-14 from cosmic radiation nor (2) the decay of radioactive isotopes in the environment is sufficient to account for the carbon-14 detected in fossil and geological samples.2

Though I think his analysis may be unrealistically simplistic, let’s assume Cupps’s calculations are correct. He still misses my point. In Dinosaur Blood and the Age of the Earth, I argue that all three possible sources simultaneously contribute to the detectable carbon-14. In other words, while no single source may fully account for the detectable carbon-14, when combined, all three can. Cupps’s analysis neglects the contribution of the ubiquitous background carbon-14 and possible sources of contamination from the environment.

Ironically, the low levels of carbon-14 detected in fossils and geological specimens by YECs actually argue against a young Earth, not an old Earth.

How can that be?

If fossil and geological specimens are between 3,000 and 6,000 years old, then somewhere between 50 and 75 percent of the original carbon-14 should remain in the sample. This amount of material should generate a strong carbon-14 signal. The fact that these specimens all age-date to 30,000 to 45,000 years old means that less than 2 percent of the original carbon-14 remains in these samples—if the results of this measurement are taken at face value. It becomes difficult to explain this result if these samples are less than 6,000 years old. On the other hand, the weak carbon-14 signal measured by YECs does make sense if carbon-14 does not reflect the material originally in the sample, but instead stems from a combination of (1) contamination from the environment, (2) ubiquitous background radiocarbon, and/or (3) irradiation of the samples by isotopes such as uranium or thorium in the environment.

To put it plainly, it is difficult to reconcile the carbon-14 measurements made by YECs with fossil and geological samples that are 3,000 to 6,000 years old, Cupps’s analysis notwithstanding.

On the other hand, an old-earth perspective has the explanatory power to account for the low levels of carbon-14 associated with fossils and other geological samples.

Resources

Endnotes

  1. Vernon R. Cupps, “Radiocarbon Dating Can’t Prove an Old Earth,” Acts & Facts, April 2017, https://www.icr.org/article/9937.
  2. Ibid.
Reprinted with permission by the author
Original article at:
https://www.reasons.org/explore/blogs/the-cells-design/read/the-cells-design/2017/04/19/does-radiocarbon-dating-prove-a-young-earth-a-response-to-vernon-r.-cupps

Does Dinosaur Tissue Challenge Evolutionary Timescales? A Response to Kevin Anderson, Part 2

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BY FAZALE RANA – JANUARY 18, 2017

What is the proper relationship between science and the Christian faith? Answering that question can be complicated, involving an interplay between science, philosophy, theology, and biblical studies. Perhaps it’s not surprising that evangelical Christians (who all take Scripture seriously) advocate disparate models, weighing differently the data and insights from science and Scripture.

The three most prominent views held by evangelical Christians are: young-earth creationism (YEC), old-earth creationism (OEC), and evolutionary creationism (EC). Each view has strengths and weaknesses. And each view accepts and rejects (or at least expresses skepticism) about certain aspects of current scientific paradigms.

It goes without saying that “in-house” discussions among adherents of these three models can become quite contentious. And for good reason: much is at stake. No one wants to undermine Scripture. And no one wants to recklessly disregard scientifically established ideas. Because to do so could compromise the Church’s ability to reach out to non-Christians. In my view, it is okay to question scientific dogma—particularly if it challenges key tenets of the Christian faith. But it is important to do so responsibly and in a scientifically credible way.

My chief motivation for writing Dinosaur Blood and the Age of the Earth was to prevent well-intentioned Christians from unwittingly undercutting their effectiveness when sharing their faith by using a seemingly compelling scientific argument for a young Earth (with the hope of demonstrating the credibility of the creation accounts from a young-Earth vantage point).

Many Christians regard the discovery of soft-tissue remnants, associated with fossilized remains age-dated to be upwards of hundreds of millions of years, as a compelling scientific evidence for a young Earth. And I can see why.

Soft tissues shouldn’t survive for millions of years. Based on common wisdom, these materials should readily degrade in a few thousand years. That being the case, the discovery of soft tissue remnants associated with fossils is a compelling reason to question the reliability of radiometric dating methods used to determine the age of these fossils, and along with it, Earth’s antiquity. Instead, YECs argue that these discoveries provide powerful scientific evidence for a young Earth and support the idea that the fossil record results from a recent global (worldwide) flood.

Yet few scientifically minded people are swayed by this argument. In Dinosaur Blood and the Age of the Earth, I explain why this increasingly prominent argument for a young Earth is invalid. First, I explain why radiometric dating methods are reliable. Secondly, I explain how it is scientifically conceivable that soft-tissue remnants could survive for upwards of hundreds of millions of years.

When I published Dinosaur Blood and the Age of the Earth, I expected responses by YECs. And there have been a few. Generally, I won’t engage in tit-for-tat when my ideas are criticized. But, I am making an exception in the case of Kevin Anderson’s recent technically rigorous article for Answers in Depth, the journal of Answers in Genesis, titled: “Dinosaur Tissue: A Biochemical Challenge to the Evolutionary Timescale.” Because Anderson is a scholar, and because his approach is fair-minded, it is important to pay attention to his critiques of my work and to engage his ideas.

In part one (of this two-part blog series), I addressed Anderson’s dismissal of the biomolecular durability argument I present in Dinosaur Blood and the Age of the Earth as part of the explanation for collagen (and keratin) survivability in fossils. In this second part, I engage Anderson’s challenges to what he refers to as “the most popular explanation for prolonged preservation” of soft tissue. Namely, the “iron model.”1

The Iron Model for Soft Tissue Preservation

As described in Dinosaur Blood and the Age of the Earth, paleontologists have noted iron deposits associated with preserved soft-tissue remnants in a number of fossilized specimens. (In fact, iron deposits were associated with the recently discovered dinosaur feathers preserved in amber, age-dated to 99 million years.2) On this basis, they speculate that the iron in conjunction with oxygen help to preserve soft-tissue materials through a variety of possible mechanisms, including: killing off microbes, inhibiting enzymes, and causing cross-linking reactions that function as a fixative (like formaldehyde), at least until mineral entombment takes place.3 The researchers posit that iron associated with hemoglobin (the protein that binds and carries oxygen found in red blood cells) is the primary source of iron. Presumably, when the organism dies, the red blood cells lyse, releasing hemoglobin and iron into the tissue.

To demonstrate the validity of this idea, researchers from North Carolina State University exposed ostrich blood vessels dispersed in an aqueous solution of ruptured blood cells. They observed iron deposits forming on the blood vessels. The blood cell lysate stabilized the soft tissue. Compared to blood vessels dispersed in water (in the presence and absence of oxygen) which lasted only a few days, blood vessels exposed to red blood lysates persisted for upwards of two years (and counting).

Yet, Anderson questions the iron model for a variety of reasons.

  • He raises doubts about the relevancy of the laboratory experiments on the ostrich blood vessels.
  • He expresses concern that the iron level in dinosaurs is insufficient for it to achieve adequate preservation, even if the iron model is valid.
  • He notes that the reactions that promote cross-linking also destroys amino acids. (Even though amino acids have been recovered from dinosaur and bird fossils.)

In my view, none of these criticisms bears much weight.

To be fair, Anderson rightly highlights a problem constantly confronting scientists studying the origin and history of life. Namely, how do chemical and physical processes identified in the laboratory under highly controlled conditions (and the auspices of researchers) translate to the uncontrolled conditions of Earth’s past environment? Though granting Anderson this point—in fact, I have raised a similar criticism toward work in prebiotic chemistry in my book Creating Life in the Lab—it is important to acknowledge that the stability experiments with ostrich blood vessels demonstrate that, in principle, the iron model has merit. It is also worth noting that the conditions employed by the researchers in the lab experiments represent a worst-case scenario, because the vessels were dispersed in water which promotes hydrolysis and microbial growth. In other words, under “real-life” conditions, iron-mediated preservation of soft tissue has an even greater likelihood than in the experiments conducted in the laboratory.

Concerning Anderson’s second point about iron abundances in dinosaurs (or ancient birds), it is noteworthy that iron from the lysed red blood cells binds to the ostrich blood vessels, suggesting some type of concentrating mechanism that localizes the iron to the soft tissue. Also, as Anderson acknowledges, there may be environmental sources of iron that could contribute to the iron pool. Even if there are still questions as to the source and available levels of iron for tissue preservation, this mechanism appears to be significant. As already noted, paleontologists have discovered iron associated with soft tissue remnants found in fossils.

As for Anderson’s third point, it is true that the reaction mediated by iron and oxygen (which drives cross-linking) alters amino acids. And it is true that unaltered amino acids are found in the fossil specimens. But these two results are not mutually exclusive. How is that possible? Because chemical reactions don'[t necessarily go to completion. To put it another way, during the preservation process, it is unlikely that all the amino acids comprising dinosaur proteins reacted via the iron and oxygen mediated reactions. Some of the amino acids will remain unaltered—even highly reactive ones. It is noteworthy that the molecular profiles of materials extracted from dinosaur fossils show a relative dearth of less stable amino acids and an abundance of more durable amino acids, exactly as expected if the amino acids come from the remnants of ancient protein specimens.4

Ultimately, my complaint with Anderson’s critiques have less to do with his scientific points, and more to do with his “either-or” posture. Even if Anderson’s critique of the iron model stands, it doesn’t mean that there is no way to account for soft-tissue preservation. As I argue in Dinosaur Blood and the Age of the Earth, there is probably no single preservation mechanism that accounts for the survival of soft tissue materials. In reality, it is a combination of mechanisms working additively (maybe, synergistically) that accounts for the persistence of soft tissue in fossils, with the iron-oxygen mechanism working in conjunction with other processes.

Other Preservation Mechanisms

In Dinosaur Blood and the Age of the Earth, I argue that many of the mechanisms that affect soft-tissue decomposition (hydrolysis via exposure to water, oxidation caused by oxygen exposure, breakdown by environmental enzymes, and microbial decomposition) can actually protect soft-tissue remnants under some circumstances.

In response to this point, Anderson argues that these claims are “self-contradictory.”5 But this is exactly my point. Conditions traditionally thought to drive soft-tissue breakdown, preserve soft tissues under certain sets of conditions. In other words, traditional views about soft-tissue decomposition aren’t likely correct.

In fact, the iron model illustrates this point. In keeping with common wisdom, exposure to oxygen drives soft-tissue destruction. Conversely, excluding oxygen during the fossilization process should aid in preservation by preventing oxidative decomposition of the soft-tissue materials. But oxidation reactions also drive cross-linking of proteins. So, exposure to oxygen also preserves soft tissues. Whether decomposition or preservation occurs depends on the specific circumstances surrounding the fossilization process, with some conditions “tipping the scale” in favor of decomposition and other conditions “moving the needle” toward preservation. And, of course, iron released from hemoglobin (or from environmental sources) accelerates the cross-linking reactions, helping to stabilize the soft-tissue materials.

Are Fossils Thousands of Years Old or Millions of Years Old?

Anderson concludes his argument by lamenting the bias of the scientific community. He says, “The problem is that the evolutionary community does not really consider the first alternative [dinosaurs aren’t as old as we think they are] as a possibility. Thus, it really is not an ‘either/or’ option. In their view the fossils must be old, therefore the tissue must somehow have survived (biochemical contradictions not withstanding). . . . No one has ever observed multi-millions of years of animal tissue preservation. The only reason there is even a quest for an unknown preservation mechanism is because evolutionary assumptions require dinosaur fossils to be at least 65 million years old.”6

Anderson’s protests not withstanding, the scientific community does not assume the fossils to be millions of years old, but has measured fossils to be millions of years old using sound, scientifically established radiometric methods. Consequently, the scientific community has observed soft tissue preserved for millions of years, with the recovery of blood vessels remnants, and protein fragments from the fossils of dinosaurs (and other organisms).

Finally, while it is true that the scientific community lacks full understanding of the mechanisms involved, preservation of soft tissues in fossils does not stand as a “biochemical contradiction.” Instead, there are sound explanations for the persistence of soft-tissue remnants in fossils. And as work continues, I predict that the scientific community will identify new preservation mechanisms. In fact, this has already happened. Researchers now think that eumelanin released from melanosomes can serve as a fixative assisting in the preservation of keratin associated with fossilized feathers, claws, and skin.7

I appreciate Kevin Anderson’s thoughtful engagement with my ideas regarding soft-tissue preservation, but I disagree with his conclusions. Simply put, soft-tissue preservation in fossils is not a valid scientific argument for a young Earth, nor does it provide evidence that the fossil record was laid down as a result of a recent, global flood.

Resources

Endnotes

  1. Kevin Anderson, “Dinosaur Tissue: A Biochemical Challenge to the Evolutionary Timescale,” Answers in Genesis 11 (2016): https://answersingenesis.org/fossils/dinosaur-tissue/.
  2. Lida Xing et al., “A Feathered Dinosaur Tail with Primitive Plumage Trapped in Mid-Cretaceous Amber,” Current Biology 26 (December 19, 2016): 3352–60, doi:10.1016/j.cub.2016.10.008.
  3. Mary Schweitzer et al., “A Role for Iron and Oxygen Chemistry in Preserving Soft Tissues, Cells and Molecules from Deep Time,” Proceedings of the Royal Society B 281 (January 2014): 20132741, doi:10.1098/rspb.2013.2741.
  4. Mary Schweitzer et al., “Preservation of Biomolecules in Cancellous Bone of Tyrannosaurus Rex,” Journal of Vertebrate Paleontology 17 (June 1997): 349–59, doi:10.1080/02724634.1997.10010979.
  5. Kevin Anderson, “Dinosaur Tissue.”
  6. Ibid.
  7. Alison Moyer, Wenxia Zheng, and Mary Schweitzer, “Keratin Durability Has Implications for the Fossil Record: Results from a 10 Year Feather Degradation Experiment,” PLoS One 11 (July 2016): e0157699, doi:10.1371/journal.pone.0157699.
Reprinted with permission by the author
Original article at:
https://www.reasons.org/explore/blogs/the-cells-design/read/the-cells-design/2017/01/18/does-dinosaur-tissue-challenge-evolutionary-timescales-a-response-to-kevin-anderson-part-2

Does Dinosaur Tissue Challenge Evolutionary Timescales? A Response to Kevin Anderson, Part 1

doesdinosaurtissuechallengepart1

BY FAZALE RANA – JANUARY 11, 2017

Is there a bona fide scientific challenge to the age of the Earth, which is measured to be 4.5 billion years old? As an old-earth creationist (OEC), I would answer no. But, there has been one scientific argument for a young Earth that has given me some pause for thought: the discovery of soft tissue remnants in the fossilized remains of dinosaurs (and other organisms). Paleontologists have discovered the remnants of blood vessels, red blood cells, bone cells, and protein fragments, such as collagen and keratin, in the fossilized remains of dinosaurs that age-date older than 65 million years.

These unexpected finds have become central to the case made by young-earth creationists (YEC) for a 6,000-year-old Earth. In effect, the argument goes like this: Soft tissues shouldn’t survive for millions of years. Instead, these materials should readily degrade in a few thousand years. Accordingly, the discovery of soft tissue remnants associated with fossils is a prima facie challenge to the reliability of radiometric dating methods used to determine the age of these fossils, and along with it, Earth’s antiquity. YECs argue that these discoveries provide compelling scientific evidence for a young Earth and support the idea that the fossil record results from a recent global (worldwide) flood.

As I detail in my book Dinosaur Blood and the Age of the Earth, there are good reasons to think that radiometric dating methods are reliable. And, that being the case, then there must be an explanation for soft tissue survival. Despite the claims made by YECs, there arescientific mechanisms that can account for the survival of soft-tissue materials for millions of years, as discussed in Dinosaur Blood and the Age of the Earth.

In response to my book (and other recent challenges) to the soft-tissue argument for a young Earth, YEC Kevin Anderson wrote a piece for Answers in Depth, the journal of Answers in Genesis, titled: “Dinosaur Tissue: A Biochemical Challenge to the Evolutionary Timescale.”

In this technically rigorous piece, Anderson argues that paleontologists now view soft-tissue remnants associated with the fossilized remains of dinosaur (and other organisms) as commonplace. On this point, Anderson and I would agree. However, Anderson complains that the scientific community ignores the troubling implications of the soft-tissue finds. He states: “Despite a large body of evidence for the authenticity of the tissue, there remains a pattern of denial within the evolutionist community—presumably to downplay the ramifications of this discovery. . . . Apparently many find the soft-tissue evidence much easier to dismiss than to understand and explain. Perhaps this should not be too surprising. The tissue is certainly difficult to account for within the popular geologic timescale.”1

Yet, in Dinosaur Blood and the Age of the Earth, I explain how soft-tissue remnants associated with fossils are accounted for within “the popular geologic timescale.”

Soft-Tissue Survival in Fossils

Once entombed within a mineral “encasement” (which occurs as the result of the fossilization process), soft-tissue remnants can survive for vast periods of time. The key: the soft tissues must be preserved until entombment happens. In Dinosaur Blood and the Age of the Earth, I identify several factors that promote soft-tissue preservation during the fossilization process. One relates to the structure of the molecules comprising the soft tissues. Some molecules are much more durable than others, making them much more likely to survive until entombment.

This durability partially explains the chemical profile of the compounds associated with soft-tissue remnants. For example, paleontologists have uncovered collagen and keratin fragments associated with dinosaur fossils. These finds make sense because these molecules are heavily cross-linked. And they occur at high levels in bones (collagen) and feathers, skin, and claws (keratin). Researchers also believe that iron released from hemoglobin, and eumelanin released from melanosomes associated with feathers, function as fixatives to further stabilize these molecules, delaying their decomposition.

But What about Measured Collagen Decomposition Rates?

Kevin Anderson agrees that some molecules, such as collagen, resist rapid degradation. However, he rejects the durability argument I present in Dinosaur Blood and the Age of the Earth as part of the explanation for collagen (and keratin) survivability, citing work published in 2011 by researchers from the University of Manchester in the UK.2

In this study, investigators monitored collagen loss in cattle and human bones at 90 °C (194 °F). Even though this high temperature doesn’t directly apply to the fossilization process, the researchers employed a temperature close to the boiling point of water to gather rate data in a reasonable time frame. Still, it took them about one month to generate the necessary data, even at this high temperature. In turn, they used this data to calculate the bone loss at 10 °C (50 °F), which corresponds to the average temperature of a typical archaeological site in a country such as Great Britain. These calculations made use of the Arrhenius rate equation. This equation allows scientists to calculate the rate for a chemical process (such as the breakdown of collagen) at any temperature, once the rate has been experimentally determined for a single temperature. The only assumption is that the physical and chemical properties of the system (in this case, collagen) are the same as the temperature used to measure the reaction rate and the temperature used to calculate the reaction rate.

But, as I discuss in Dinosaur Blood and the Age of the Earth, if the conditions differ, then a phenomenon known as an Arrhenius plot break occurs. This discontinuity makes it impossible to calculate the reaction rate.

On this basis, I questioned if the data generated by the University of Manchester scientists for collagen breakdown in bone near the boiling point of water is relevant to breakdown rates for temperatures that would be under 100 °F, let alone to temperatures near 50 °F. I speculated that at such high temperatures, the collagen would undergo structural changes (for example, breaking of inter-chain hydrogen bonds that cross-link collagen chains together) making this biomolecule much more susceptible to chemical degradation than at lower temperatures where collagen would remain in its native state. In other words, the conditions employed by the research team from the University of Manchester may not be relevant to collagen preservation in fossil remains.

Kevin Anderson challenged my claim, stating, “Dr. Rana speculates that high temperatures may unexpectedly alter how collagen will degrade, so perhaps the Arrhenius equation cannot be properly applied. However, he fails to offer any experimental support for his conclusion. If he wants to challenge these decay studies, he needs to provide experimental evidence that collagen decay is somehow an exception to this equation.”3

Fair enough. Yet, it was relatively easy for me to find the experimental data he requires. A quick literature search produced work published in the early 1970s by a team of researchers from the USDA in Beltsville, MD describing the thermal denaturation profiles of intact collagen from a variety of animal sources.4 The onset temperatures for the denaturation process typically begin near 60 °C (140 °F), reach the mid-point of the denaturation around 70 °C (158 °F), and end around 80 °C (176 °F). In other words, collagen denaturation occurs at temperatures well below the temperatures used by the University of Manchester scientists in their study.

From the denaturation profiles, these researchers determined that the loss of native structure primarily entails the unraveling of the collagen triple helix. This unraveling would expose the protein backbone, making it much easier to undergo chemical degradation.

In Dinosaur Blood and the Age of the Earth, I discuss another reason why the study results obtained by the University of Manchester scientists don’t contradict the recovery of collagen from 70–80 million-year-old dinosaur remains. In effect, this research team was addressing a different question. Namely, how long can collagen last in animal remains in a form that can be isolated and used as a source of genetic information about the organisms found at archaeological and fossil sites?

In other words, they weren’t interested in how long chemically and physically altered collagen fragments would persist in fossil remains, but, instead, how long collagen will retain a useful form that can yield insight into the natural history of past organisms. Specifically, they were interested in the survival of “the non-helical collagen telopeptides located at the very ends of each chain and recently considered potentially useful for species identification in archaeological tissues.”5

The researchers lament that this region of the collagen molecules is “lost to the burial environment within a relatively short period of geologic time.”6 As they point out, the parts of the collagen molecule most useful to characterize the natural history of past organisms and their relationships to extant creatures, unfortunately, are “regions of the protein that do not benefit from as many interchain hydrogen bonds as the helical region, and thus will likely be the first to degrade.”7

The researchers also point out that they expect collagen to persist for much longer than 700,000 years, but in a chemically altered state due to cross-linking reactions and other types of chemical modifications. They state, “Collagen could plausibly be detected at lower concentrations [than 1 percent of the original amounts] in much older material but likely in a diagenetically-altered state and at levels whereby separation from endogenous and exogenous contaminations is much more time-consuming, costly and perhaps applicable only to atypically large taxa that can offer sufficient fossil material for destructive analysis.”8

In other words, chemically altered forms of collagen will persist in animal remains well beyond a million years, particularly if they are large creatures such as dinosaurs. And this is precisely what paleontologists have discovered associated with dinosaur fossils—fragments of diagentically altered collagen (and keratin).

But What about Molecular Fragments Derived from Non-Durable Proteins Isolated from Dinosaur Remains?

Another related challenge raised by Anderson relates to the recovery of molecular fragments of other proteins from dinosaur fossils that are much less durable than collagen. Anderson writes: “Several of these proteins (e.g., myosin, actin, and tropomyosin) are not nearly as structurally ‘tough’ as collagen. . . . Even if there were a biochemical basis that enabled collagen fragments to survive millions of years, this cannot be said about all these other dinosaur proteins.”9

As I point out in Dinosaur Blood and the Age of the Earth, in addition to molecular durability, there are several other factors that contribute to soft-tissue preservation. One relates to abundance. Biomolecules that occur at high levels in soft tissue will be more likely to leave behind traces in fossilized remains than molecules that occur at relatively low levels.

Along these lines, collagen and keratin would have been some of the most abundant proteins in dinosaurs and ancient birds, making up connective tissue and feathers, skin, and claws, respectively. Likewise, actin, myosin, and tropomyosin would also have occurred at high levels in dinosaurs and ancient birds, because these proteins are the major components of muscle. So even though these proteins aren’t as durable as collagen or keratin, it still makes sense that fragments of these biomolecules would be associated with dinosaur fossils because of their abundances.

In short, the durability and abundances of proteins provide a credible explanation for the occurrence of soft-tissue remnants in the fossilized remains of dinosaurs. But these two features don’t fully account for soft-tissue preservation. As it turns out, there are additional factors to consider.

In his article, Anderson also challenges what he refers to as “the most popular explanation for prolonged preservation” of soft tissue. Namely, the “iron model.”10 In part 2 of my response to Kevin Anderson, I will describe and respond to his critique of the iron model and other preservation mechanisms.

Resources

Endnotes

  1. Kevin Anderson, “Dinosaur Tissue: A Biochemical Challenge to the Evolutionary Timescale,” Answers in Genesis 11 (2016): https://answersingenesis.org/fossils/dinosaur-tissue/.
  2. Mike Buckley and Matthew James Collins, “Collagen Survival and Its Use for Species Identification in Holocene-Lower Pleistocene Bone Fragments from British Archaeological and Paleontological Sites,” Antiqua 1 (2011): e1, doi:10.4081/antiqua.2011.e1.
  3. Anderson, “Dinosaur Tissue.”
  4. Philip E. McClain and Eugene R. Wiley, “Differential Scanning Calorimeter Studies of the Thermal Transitions of Collagen: Implications on Structure and Stability,” Journal of Biological Chemistry 247 (February 1972): 692–97, https://www.jbc.org/content/247/3/692.full.pdf.
  5. Buckley and Collins, “Collagen Survival.”
  6. Ibid.
  7. Ibid.
  8. Ibid.
  9. Anderson, “Dinosaur Tissue.”
Reprinted with permission by the author
Original article at:
https://www.reasons.org/explore/blogs/the-cells-design/read/the-cells-design/2017/01/11/does-dinosaur-tissue-challenge-evolutionary-timescales-a-response-to-kevin-anderson-part-1

Can Keratin in Feathers Survive for Millions of Years?

cankeratininfeatherssurvive

BY FAZALE RANA – AUGUST 10, 2016

I don’t like conflict. In fact, I try to avoid it whenever possible. And that’s part of the reason I never wanted to become directly involved in the young-earth/old-earth controversy that takes place within the church.

Frankly, I find the debate tedious, and a distraction from the real work at hand: helping skeptics and seekers recognize the scientific evidence for God’s existence and Scripture’s reliability.

Of course, if people ask me age-of-the-earth questions, I am quick to explain why I hold to an old-earth/day-age interpretation for Genesis 1 and what I see as biblical, theological, and scientific issues with a young-earth/calendar day interpretation of the Genesis 1 creation account.

Soft Tissues in Fossils and the Age of the Earth

Over the course of the last few years, one question that has come up a lot relates to the discovery of soft tissue remnants in fossils, such as the blood cells and blood vessels remains recovered from a T. rex specimen that age-dates to 68 million years old. Young earth creationists make use of these surprising results to argue that it is impossible for fossils to be millions of years old. They argue that soft tissues shouldn’t survive that long. These materials should readily degrade in a few thousand years. In their view, these finds challenge the reliability of radiometric dating methods used to determine the age of these fossils, and along with it, Earth’s antiquity. Instead, they argue that these breakthrough discoveries provide compelling scientific evidence for a young Earth and support the idea that the fossil record results from a recent global (worldwide) flood.

Because I’m a biochemist—and an old earth creationist—people frequently ask me how I make sense of the T. rex find and the discovery of other types of soft tissue remnants in the fossil remains of other creatures that age-date to several hundred million years, in some cases.

Dinosaur Blood and the Age of the Earth

These queries eventually motivated me to write Dinosaur Blood and the Age of the Earth. And I am glad I did. Aside from the young-earth/old-earth debate, the scientific questions related to soft tissue finds in fossils are captivating.

The central question of Dinosaur Blood and the Age of the Earth centers around soft tissue durability: If radiometric dating is reliable, then how is it possible for soft tissue remnants to persist for millions of years?

Recent work by a research team at North Carolina State University (NC State)—headed up by Mary Schweitzer—helps address this question, specifically focusing on beta-keratin fragments recovered from the fossilized feathers and claws of Shuvuuia deserti and Rahonavis ostromi.1

How Can Keratin Survive in Fossils?

As I discuss in Dinosaur Blood and the Age of the Earth, some biomolecules (such as keratins) form extremely stable structures that delay their degradation. Keratins have a number of structural features (such as extensive crosslinking) that helps explain why fragments of these proteins could survive for tens of millions of years, under the right conditions.2 But my analysis was theoretical. Even though my assessment was based on sound biochemical principles, it would be nice to have some corroborating experimental evidence to support my claims. (The old saying in science applies: “theories guide, experiments decide.”) And that is precisely what the NC State researchers provide in their recent study.

Feather Decomposition

Schweitzer and her team conducted a ten-year experiment to gain insight into the natural degradation processes of feathers (and other biological materials made up of keratins such as skin, claws, beaks, and hair). To do this, they exposed feathers from a Hungarian partridge to a variety of conditions, and then analyzed the samples busing: (1) transmission electron microscopy (TEM) to monitor changes in the fine structure of the feather’s anatomy; and (2) a technique called in situ immunofluorescence to determine if pieces of keratin proteins persisted in the feather remains.

Of particular interest is the feather samples Schweitzer and her team wrapped in aluminum foil and heated in an oven for 10 years at 630°F—conditions used to sterilize glassware. Many paleontologists consider high heat to be a proxy for deep time.

Perhaps it is no surprise, when viewed under a microscope, the macroscopic features of feathers treated at high temperatures were completely lost. Instead the only thing visible were shiny black pieces of “charcoal-like” material. Yet, when examined at high magnification with a TEM, the investigators were able to visualize fragments of feather barbs. Using their immunofluorescence technique, the researchers were able to detect clear evidence of keratin fragments in the sample.

These observations align with my thoughts about keratin’s durability, making it all the more reasonable to think that soft tissue remnants persist in millions-of-years old fossil remains. In fact, when the researchers applied their immunofluorescence to the Shuvuuia desertisamples, once again, they found evidence for keratin fragments in these fossil remains.

Preservation Mechanisms

As I point out in Dinosaur Blood and the Age of the Earth, molecular durability alone isn’t sufficient to account for soft tissue survivability. For soft tissue remnants to persist in fossil, the rate of fossilization has to outpace the rate of soft tissue degradation. When that happens, a mineral ‘casing’ will entomb the soft tissue before it completely decomposes, preserving it for paleontologists to later discover. In addition to molecular durability, scientists have identified a number of mechanisms that contribute to both the degradation and preservation of soft tissues during the process of burial and fossilization.

Along these lines, the NC State scientists speculate on processes that might extend keratin’s survivability in feathers—at least, long enough for mineral entombment to occur. They think one of their observations about the high-heat sample offers a clue. The research team noted that melanosomes (the organelles that harbor pigments, giving feathers their colors) were absent after heating for ten years at 630°F. On this basis, they conclude that paleontologists have made a mistake when they interpret microbodies as melanosomes in fossilized feathers. Instead, they think that the mirobodies derive from microbes.

This reinterpretation is good news for keratin preservation on two accounts. It is true that microbial activity can destroy soft tissues, but the NC State scientists think it can also help speed up the fossilization process leading to the preservation of keratin remnants. How? Because microbes secrete materials (called exopolymeric substances) that promote deposition of minerals, speeding up the entombment of the soft tissue. Additionally, the NC State researchers think that melanosome degradation may also be important. When these organelles break down, they release their contents (eumelanin) which may function like a fixative, slowing down tissue degradation long enough for the soft tissue to be entombed.

The NC State study has unearthed fascinating details regarding feather decomposition and provides key insights that help account for the persistence of keratin in fossilized remains of reptiles, birds, and feathered dinosaurs that date to tens of millions of years old.

Resources
Structure of Collagen Unravels the Case for a Young Earth” by Fazale Rana (Article)
Dinosaur Blood and the Age of the Earth by Fazale Rana (Book)

Endnotes

  1. Alison Moyer, Wenxia Zheng, and Mary Schweitzer, “Keratin Durability Has Implications for the Fossil Record: Results from a 10 Year Feather Degradation Experiment,” PLoS One 11 (July 2016): e0157699, doi:10.1371/journal.pone.0157699.
  2. Fazale Rana, Dinosaur Blood and the Age of the Earth (Covina, CA: RTB Press, 2016), 57–58.
Reprinted with permission by the author
Original article at:
https://www.reasons.org/explore/blogs/the-cells-design/read/the-cells-design/2016/08/10/can-keratin-in-feathers-survive-for-millions-of-years