The Wonder Material: Cartilage

The formerly simple tissue turns out to be
both more complex and masterly designed

 

by Jerry Bergman, PhD

Cartilage, the flexible connective tissue that keeps joint motion fluid by coating the surfaces of the bones in our joints turns out to be far more complex than previously imagined. The function and design of this coating that covers other tissues, including bones at the joint, would seem to be straightforward, but as one study admitted,

Exactly how cartilage manages this near-frictionless, shock absorbing function is not fully understood. It is generally accepted that it depends on interactions between fluid in the joint and the molecules that make up the tissue, known as the extracellular matrix (ECM). Studying these subtle dynamics at the microscopic level has long been a goal of scientists.[1]

What Cartilage Does for Us

Cartilage is a seemingly simple substance that has numerous important functions in the body. This stiff rubber-like elastic tissue also has a structural function, including as part of the rib cage, the ear, nose, intervertebral discs, and even the bronchial tubes. In short, it is everywhere and is even used to hold tubes open, such as the rings of the trachea (commonly called the windpipe) in the cricoid cartilage. This cartilage type consists of strong connective tissue constituting the dorsal part of the larynx, or voice box.

In summary, cartilage is a vital construction material which holds the body together. It is avascular (i.e., it does not contain blood vessels) and aneural (it does not contain nerves), thus it does not feel pain, but heals slowly.

One of cartilage’s major roles is to coat the ends of our bone joints, allowing them to smoothly glide past one another.  The surface it creates is about five times more slippery than ice on ice. It also cushions bones, helping to protect them against the force of impact, which can be enormous. In a healthy adult male, the femur can support 30 times the body weight. For the average adult male, this equals roughly 6,000 pounds of compressive force! Understanding this “simple substance” has required scientists to develop some of the most sophisticated research tools ever invented.

The New Study Method

To understand the miracle of cartilage, Researchers at the Argonne National Laboratory employed X-ray photon correlation spectroscopy using ultra-bright X-ray beams produced by their Advanced Photon Source (APS) system.[2] This system allowed them to observe the dynamics of the extracellular matrix at scales never previously achieved – less than one micron, 70 times smaller than the width of a human hair.[3] The goal of the research was to better understand and treat cartilage problems and diseases such as osteoarthrosis.

Another study by Partain et al. in 2021 determined that cartilage “behaves as a biphasic material, where material mechanics derives from a fluid phase, solid phase, and interaction between the two.”[4] They found that cartilage integrates several materials that alter their function according to changes in temperature, pressure, and other factors as the extracellular matrix is in motion. For example, when hydrated,

cartilage matrix dynamics are depth dependent, with matrix dynamics fastest at the cartilage surface and progressively slowing with increased depth…. Healthy cartilage has a hierarchical structure that is often described as three different zones: surface zone, middle zone, and deep zone. Each zone has a different structural composition that affects matrix mobility.”[5]

This design allows cartilage to function very effectively in its many roles and locations in the body. The Partain study concluded that cartilage

tissues have complex structures that provide complex physical functions. These functions derive from interactions occurring across length scales. However, many questions remain in how tissue interactions provide mechanical function.[6]

Cartilage Evolution Baffles Evolutionists

As shown above, scientists still do not understand how cartilage achieves its near frictionless shock absorbing capability. That has not stopped Darwinists from claiming it evolved, but they have to admit they are baffled by its origin. In a 2016 paper in Current Biology about animal evolution, Brunet and Arendt confessed, “it remains a mystery how cartilage itself first arose in evolution.”[7]

Frankly, there is no evidence for the origin of this complex substance from simpler substances. It exists in even some ‘simple’ so-called ‘primitive’ animals, including a few isolated groups of protostomes (e.g., worms, arthropods, mollusks): chelicerates (e.g., arachnids, sea spiders, horseshoe crabs) and cephalopods (e.g., squid, octopus). Though unrelated according to evolutionists, the cartilage composition in a wide variety of animals, from cuttlefish, horseshoe crabs, fish, mammals to humans is structurally very similar. Animals either utilize cartilage or use some other very different support system such as chitin. Chitin is a tough, protective, semitransparent nitrogen-containing polysaccharide used in many insects. Nothing in between chitin and cartilage—nor any evidence of cartilage evolution—has ever been found.

This scattered distribution requires evolutionists to imagine that “cartilage evolved independently in each of these groups and was not present in their last common ancestor.”[8] The problem with this explanation is obvious: no evidence exists it evolved even once, so to postulate it evolved numerous times multiplies the implausibility of the story.

Fossils Don’t Help

Although animal bones are the bread and butter of the fossil trade, we have no evidence of bone evolution either! Consequently, for

the evolutionary biologist, the hard parts of animals are similarly double-faced: their endurance makes them the prime candidates for fossilization and provides paleontologists with a wealth of information on the skeleton of extinct animals. From the paleontologist’s view, animal evolution is thus mainly the evolution of hard parts (plus what can be deduced from them). But for the same reason, the origin of the first animal skeletons, and the ancestral structures that gave rise to them in soft-bodied animals, remains mysterious.[9]

Cartilage as soft tissue is often not preserved in the fossil record, but bones are. Brunet and Arendt admit that for over

a century, morphologists have been debating, with precious little evidence, the hard questions of skeleton origins: When did animal skeletons first evolve? Did they appear once or several times independently? Which ancestral soft tissues first became rigid, and by what molecular mechanisms?[10]

This leaves evolutionists in the dark about the origin of animal skeletons. Since cartilage is believed to be the “evolutionary precursor to vertebrate bones,” the fact that bones show no evidence of evolution either leaves both substances unexplained. The theory that bones evolved from cartilage is merely a combination of two imaginary scenarios.

Summary

Cartilage follows a trend I have seen in human anatomy studies. When investigated more closely, it is a far more complex structure than previously believed. The evidence of the evolution of this complex structure has so far eluded evolutionists, as has the evolution of bone from cartilage. Evolutionists attempt to push the origin of these materials much further back in the fossil record than evidence provides. The record shows that, among living animals, no phylogenetic pattern of cartilage used only in certain animals (such as higher vertebrates) has been found. Cartilage is scattered in animal life from some very primitive organisms to many of the most advanced organisms. This is contrary to what they should expect: namely, its absence in the lowest life forms to its being increasingly more common as they go up the evolutionary ladder.

References

[1] Malooley, J., Sliding into place: Study shows how cartilage interacts with the joints in our bodies, Argonne National Laboratory, 14 March 2022. https://www.anl.gov/article/sliding-into-place-study-shows-how-cartilage-interacts-with-the-joints-in-our-bodies.

[2] Partain, B.D., et al., Spatially-resolved nanometer-scale measurement of cartilage extracellular matrix mobility, Osteoarthritis and Cartilage 29(9):1351-1361, September 2021.

[3] Malooley, 2022.

[4] Partain et al., 2022, pp. 1354-1355.

[5] Partain et al., 2022, p. 1354.

[6] Partain et al., 2022, p. 1356.

[7] Brunet, T., and D. Arendt, Animal evolution: The hard problem of cartilage origins, Current Biology 26(14), R667–R688, , https://www.cell.com/current-biology/pdf/S0960-9822(16)30562-0.pdf, 25 July 2016.

[8] Brunet and Arendt, 2016, p. R686; italics added.

[9] Brunet and Arendt, 2016, p. R685.

[10] Brunet and Arendt, 2016, p. R686.

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Dr. Jerry Bergman has taught biology, genetics, chemistry, biochemistry, anthropology, geology, and microbiology for over 40 years at several colleges and universities including Bowling Green State University, Medical College of Ohio where he was a research associate in experimental pathology, and The University of Toledo. He is a graduate of the Medical College of Ohio, Wayne State University in Detroit, the University of Toledo, and Bowling Green State University. He has over 1,300 publications in 12 languages and 40 books and monographs. His books and textbooks that include chapters that he authored are in over 1,500 college libraries in 27 countries. So far over 80,000 copies of the 40 books and monographs that he has authored or co-authored are in print. For more articles by Dr Bergman, see his Author Profile.