• stephenstrent7

Who Hath Ears to Hear

Updated: Jan 8

Trent Stephens, PhD

We read in Deuteronomy 29:2-4, “And Moses called unto all Israel, and said unto them, Ye have seen all that the Lord did before your eyes in the land of Egypt unto Pharaoh, and unto all his servants, and unto all his land; The great temptations which thine eyes have seen, the signs, and those great miracles: Yet the Lord hath not given you an heart to perceive, and eyes to see, and ears to hear, unto this day.”

In the New Testament, the Savior admonished his followers at least eight times:

Matthew 13:9 “Who hath ears to hear, let him hear.”

Mark 4:9 “And he said unto them, He that hath ears to hear, let him hear.”

As with almost all scripture, the Savior told us to hear but he did not tell us how to hear. I will combine in this essay two statements by President Russell M. Nelson that relate to hearing. One statement was made during a press conference on January 16, 2018 that followed his announcement as the 17th president of The Church of Jesus Christ of Latter-day Saints, as reported in the Deseret News by Daniel Peterson (January 25, 2018). Asked “how to attract millennials to the faith and retain them” President Nelson responded: “‘help them to appreciate eyes that see and fingers that feel and ears that hear.’” He continued, “‘That’s not an accident. That’s a gift from their Creator. So I would start right there.’”

A little under three years earlier, on April 9, 2015, the then Elder Nelson was at BYU dedicating the new Life Sciences Building. Marianne Prescott paraphrased Elder Nelson in the LDS Church News, “There will always be more to learn, the apostle said, especially when studying topics that relate to the creation, physiology and laws of life.”

As a development biologist who has studied, taught, and written about prenatal human development for the past fifty years, I will start at the beginning and outline some of the “laws of life” concerning the formation of the ears – more specifically, the tympanic membrane (eardrum).

The external ear and eardrum begin forming in the human embryo at what is called Carnegie stage 10. The embryo is about 22-23 days old and is approximately 2-3.5 mm long (about one tenth of an inch). The embryo has between 4 and 12 pairs of body segments called somites. At this stage of development, the first two pharyngeal arches or branchial arches (Greek, branchial, meaning gill) have formed. Do human embryos have gills? No, but they have the nearly identical structures that in other animals, such as fishes and amphibians will become gills. This will be explained more fully below.

Figure 1. bird.cac.med.kyoto-u.ac.jp/gallery/GrossPicture/cs10.html; for stunning TEM views of a stage 10 human embryo see embryology.med.unsw.edu.au/embryology/index.php/Carnegie_stage_10

Carnegie stages are a standardized descriptive system of 23 stages, based on work by George Streeter (1942) and Ronan O'Rahilly and Fabiola Müller (1987), and supported by the Carnegie Institution of Washington. The stages cover the first 60 days of development and are based on the development of specific structures in human embryos. After approximately 60 days, the term embryo is commonly replaced by the term fetus. At this point, most adult structures are present and further development is primarily a matter of growth.

In human embryos, the external ear will eventually form from these two pharyngeal arches, along with the jaws from the first arch; and the tympanic membrane will form between the two arches.

A few days later, the human embryo has reached Carnegie stage 12. The embryo is about 26-30 days old, is approximately 5 mm long (about two tenths of an inch), and has 21 somites. At this stage, the embryo has three pharyngeal arches. The first arch is divided into the maxillary and mandibular processes, with the future mouth forming in between. The second arch is called the hyoid arch and the tympanic membrane will form from the first pharyngeal groove, between the mandibular portion of the first arch and the second (hyoid) arch.

Figure 2. Human Embryo Carnegie Stage 12; Carnegie Collection Embryo No.5923; for stunning TEM views of a stage 10 human embryo see embryology.med.unsw.edu.au/embryology/index.php/File:Stage12_sem1.jpg

After a few more days, the human embryo has reached Carnegie stage 14. The embryo is about 33 days old, is approximately 5 to 7 mm long (still about two tenths of an inch), and has 37 somites. At this stage, the embryo has three pharyngeal arches and a reduced fourth arch. The first arch is divided into the maxillary and larger mandibular processes, with the future mouth (stomodeum) forming in between. The tympanic membrane will form from the first pharyngeal groove, between the mandibular portion of the first arch and the hyoid arch. The tail is clearly present in the photo below. Yes, human embryos have tails.

Figure 3. Human Embryo Carnegie Stage 14; Carnegie Collection Embryo No.1380

The stage 14 human embryo looks remarkably similar – especially the pharyngeal arches – to a mouse embryo, a lizard embryo, and a chick embryo. (See the next three figures.) Interestingly, a major difference between the human embryo and the other three is that the human head at this age is smaller than that of the mouse and much smaller than that of the lizard or chick.

Figure 4. Mouse Embryo E10.5; <pubmed>22615991</pubmed>| PMC3355134 | PLoS ONE; 2012 Wang et al.

Figure 5. Lizard (Anolis – a type of iguana) embryo. Photo credit: Anolis embryo by Hendrik Bringsoe

Figure 6. 96 hour chick embryo. Although there are numerous photos of chick embryos, most are too darkly stained to see the pharyngeal arches very well, so I have chosen this drawing from a classic lab manual of embryology. Watterson, Ray L. and Robert M. Sweeney, Laboratory Studies of Chick, Pig and Frog Embryos, Burgess Publishing Company, Minneapolis, Minn, 1970

Even experts in developmental biology have a difficult time telling to which class of animal a specific embryo belongs.

Figure 7. Pharyngeal arches of a human (A), Mouse (B), Lizard (C), and Bird (chick, D) embryo. The images were traced from Figures 3-6.

Life Law #1: Embryos of very different animals (even at the level of class) resemble each other more closely than they do adult members of their own species.

In 1866, Ernst Haeckel coined the phrase “ontogeny [embryonic development] recapitulates phylogeny [evolution].” The concept of recapitulation was initially proposed in the 1790s by Johann Meckel and was formalized in 1826 by Étienne Serres, and was thereafter known as the “Meckel–Serres law.” The problem with this “law” was that it proposed that embryos pass through successive stages that recapitulate the adult forms of less complex organisms (Figure 8A). For example, Haeckel proposed that the pharyngeal grooves between the pharyngeal arches of human embryos not only resemble the gill slits of fish, but are directly derived from those adult structures.

The Meckel–Serres law was opposed by Karl Ernst von Baer's theory of divergence from a common ancestor (Figure 8B). That common starting point for fish, frog, and bird (as shown in Figure 8B) points to evolution from a common ancestor. Charles Darwin argued that embryos resemble each other because they share a common ancestor, which presumably developed from embryos resembling those of its descendants. However, Darwin saw no reason to suppose that an embryo at any stage resembled an adult of any ancestor.

Figure 8. Embryology theories of Ernst Haeckel (A) and Karl Ernst von Baer (B) compared; illustration by Ian Alexander

Modern evolutionary/developmental biology (evo-devo) is founded upon von Baer’s theory of divergence in suggesting that gene changes in the timing (heterochrony) and/or positioning (heterotopy) of developing embryonic structures lead to divergence into a variety of adult structures. Many of the genes involved in development have been identified and even localized in time and space during the developmental process. However, many of the connections between gene expression and specific morphological changes are yet to be fully determined. In my opinion, there remains a lot of room for discovering additional laws of life governing such changes.

The similar pharyngeal structures seen in Figure 7 result from what C.H. Waddington, in 1942, called canalization, which channels specific structures, much like a ball rolling down a hill will follow a valley between ridges. The valley and ridges of what Waddington in 1957 called the epigenetic landscape (epigenetic means built upon the underlying pattern of gene expression; Figure 9).

Figure 9. C.H. Waddington’s epigenetic landscape; The Strategy of the Genes, London : George Allen & Unwin.

In the case of embryonic pharyngeal structure, the canalized valley is apparently so old (phylogenetically) and deep that modern embryos such as birds, lizards, mice, and humans must traverse the valley before they can diverge into class-specific morphologies. Furthermore, that epigenetic valley also points backward toward a common starting point for a specific morphology, such as the pattern of pharyngeal arches. At this point, I will propose a second law of life.

Life Law #2: Specific embryonic morphologies result from canalized valleys based upon an epigenetic landscape, and what I call a hypogenetic landscape, which is more physics-based and underlies the expression of genes (I will discuss this concept in a separate essay).

In my opinion, it is because of a specific, yet to be identified canalized valley (or valleys) that bird, lizard, and mammalian embryos develop pharyngeal arch three and pharyngeal grooves two and three, but eliminate all those on their way to becoming fetuses (Figure 10).

Figure 10. Development of the Pharyngeal arches (PA), Pharyngeal grooves (PG), and Pharyngeal pouches (PP); along with primordia of the thyroid, palatine tonsils, parathyroids, thymus, and postbranchial body (M: Mandibular process of pharyngeal arch one; H: Hyoid arch: Pharyngeal arch 2). A: Stage 14 human embryo. The line shows the line of section through the pharyngeal structures to reveal the sections shown in figures B and C. B: Section of a stage 18 human embryo. The arrows show the overgrowth of processes to close off the cervical sinus and pharyngeal grooves 2 and 3. C: Section of a stage 20 human embryo.

Once the pharyngeal grooves are formed, grooves two and three never function but are closed off by tissue overgrowth from pharyngeal arch two, or two and four (see Figure 10B), and eventually disappear. These tissue overgrowths, especially that from pharyngeal arch two, are called opercular flaps, which actually matures into the operculum of fishes. The temporary space formed by these flaps is called the cervical sinus. In certain cases of birth defects the cervical sinus never disappears and remains as a cervical fistula, just below the ear. Following a law of life not enumerated here, the epithelial tissue inside the fistula becomes glandular, and fluid, like saliva, leaks to the outside through the opening of the fistula.

The canalization of the pharyngeal arches, grooves, and pouches facilitate the formation of several glands in the newborn neck and thorax. The thyroid gland is paired in birds, variable in reptiles and single in mammals. The thymus and parathyroids are very important in all these animal groups. On the other hand, fish have thymus and thyroid tissue but lack parathyroid glands. Therefore, it appears that reptiles, birds, and mammals must traverse this pharyngeal canalized valley in order for these critical glands to form.

The search for genes that underlie the epigenetic landscape and create valleys such as those for pharyngeal development has been ongoing for over one hundred years. A large part of this search has followed the trail of so-called homeotic mutants. William Bateson first discovered homeotic transformations in 1894; for example, the antennae of some insects have been found to transform into a leg – a normal structure but appearing in an abnormal location (homeotic). Then in 1915, Calvin Bridges, working in Thomas Hunt Morgan's laboratory at Columbia University, discovered the first homeotic mutant – the mutant occurred in a fruit fly (Drosophila melanogaster), consisted of partial duplication of the thorax, and was therefore named Bithorax (bx). Since then, numerous additional homeotic mutants have been discovered, belonging to a few families of control genes (genes that control the expression of other genes).

Then, in 1963, E.B. (Ed) Lewis at Caltech, by causing a mutation in the Bithorax complex (BX-C), produced a Drosophila with four wings, resembling a dragonfly, an insect of much greater antiquity. Then, in 1978, Lewis showed that by deleting the BX-C, he could produce Drosophila embryos with a succession of 10 thoracic-like segments, resembling a centipede. Lewis proposed that homeotic genes were arranged in a chromosomal order collinear with their expression pattern along the body axis. It was later discovered that this rule of collinearity not only applies to fruit flies but to all animals, including humans. For this work, Ed Lewis, along with Christiane Nüsslein-Volhard and Eric F. Wieschaus won the Nobel Prize in Physiology or Medicine in 1995.

Life Law #3: It is my opinion that what is commonly called Lewis' rule or Lewis’ principle of collinearity is actually one of the laws of life. This law states that at least homeotic genes are arranged in the same sequence on their respective chromosomes as they appear through time in the developing embryo.

Ray Wu at Cornell University developed the first method for DNA sequencing in 1970 and very early on the new sequencing technique was turned to discovering the DNA sequence of homeotic genes. In 1983, two research groups: Ernst Hafen, Michael Levine, and William McGinnis (in Walter Gehring's lab at the University of Basel, Switzerland) and Matthew Scott and Amy Weiner (in Thomas Kaufman's lab at Indiana University, Bloomington), independently discovered a DNA sequence, 180 base pairs long, that showed up in every homeotic gene sequenced. This sequence was dubbed the homeobox. Very soon, the name was shortened to Hox, and ever since, the role played by Hox genes in patterning embryos has been a major research enterprise.

In 2018, Julie Gordon wrote a review article in the International Journal of Developmental Biology (62, 775-783), in which she stated, “It is well known that Hox genes control spatial identity along the anterior-posterior axis of the developing vertebrate embryo, and nowhere is this more evident than in the pharyngeal region. Each of the distinct segmented regions has a unique pattern of Hox expression...” She then stated, “…HOXA3 is responsible for specifying organ identity within the third pharyngeal pouch, and in its absence, thymus and parathyroid organogenesis fails to proceed normally.”

Jena Chojnowski (Development, 141:3697-708, 2014) had previously stated, “…the Hoxa3 null mutant lacks third pharyngeal pouch derivatives, the thymus and parathyroids…and organ-specific markers are absent or downregulated during initial organogenesis…Our current analysis of the Hoxa3 null mutant shows that…the location and timing of key regional markers within the pouch, including Tbx1, Bmp4 and Fgf8 (all downstream genes involved in general tissue growth and patterning), were altered.” She concluded that, “These data show that Hoxa3 has multiple complex and tissue-specific functions during patterning, differentiation and morphogenesis of the thymus and parathyroids.”

Although much research remains, we are beginning to map the patterning of genes underlying the gene interactions responsible for the epigenetic landscape (Figure 11).

Figure 11. The gene interactions underlying C.H. Waddington’s epigenetic landscape; The Strategy of the Genes, London : George Allen & Unwin. The pegs represent the genes and the lines represent the gene interactions. Four of those interacting genes would be Hoxa3, Tbx1, Bmp4 and Fgf8.

In addition to the pharyngeal pouch derivatives just described, each pharyngeal arch contains a specific cartilage, artery (called an aortic arch), and nerve. In human embryos, the first and second aortic arches form and then disappear. Although those two arches last for barely a whisper, their appearance opens a crucial valley for the appearance of the remaining two major arches, which play a vital role in the very life-blood of the individual. The third arches become the bases of the internal carotid arteries. The left fourth arch becomes the aortic arch of the adult. Without the canalization to form an epigenetic valley having the first two aortic arches at the head, the internal carotid arteries, which supply blood to the brain, and the aorta would not form.

The cartilage of the mandibular process of the first pharyngeal arch is called Meckel’s cartilage. It gives rise to the malleus and incus of the middle ear, as well as to the sphenomandibular ligament, which attaches the mandible to the base of the skull. Although Meckel’s cartilage extends far into the mandible, the bone of the jaw itself is derived from dermal bone, just as in fishes, and the cartilage is in the same location, serving the same function as the mandibular portion of the hyomandibular bone in fishes. In amphibians, birds, and reptiles, the hyoid portion of the hyomandibular bone is transformed into the columella, and then the stapes in mammals. That bone is derived from Reichart’s cartilage in the second, or hyoid, arch. Again, this system shows a powerful canalization of these middle ear cartilages and bones. Without this specific epigenetic valley, there would be no middle ear bones and we would not hear much of anything.

The core of each pharyngeal arch consists of mesenchyme – loosely packed embryonic cells – also known as mesoderm (middle layer) comprised mostly of neural crest cells, which migrated into the face from the top of the head as the neural tube was closing to form the brain; just like in every other animal with a brain of any kind. The pharyngeal grooves are lined with ectoderm (outside layer) and the pharyngeal pouches are lined with endoderm (inside layer). Both ectoderm and endoderm are epithelial tissue, consisting of one or more layers of cells sitting on a basement membrane. Epithelial tissue has no blood vessels so both the ectoderm and endoderm depend on the mesoderm to bring critical nutrients and oxygen to their cells via capillaries within the mesoderm. Take away the mesoderm and the ectoderm and endoderm simply die.

That is exactly what happens in animals with gills. The mesenchyme between the ectoderm of the pharyngeal groove and endoderm of the pharyngeal pouch migrates away or dies by apoptosis (programmed cell death), leaving the basement membranes of the ectoderm and endoderm in direct contact, with no mesenchyme or capillaries in between. With no blood supply, the epithelial layers die, leaving a hole, or slit, between the outside world and the interior pharynx. This process happens between every pharyngeal groove and pouch in animals with gills – many of which have far more grooves and pouches than we possess. The ectoderm, mesenchyme, and endoderm of the adjacent pharyngeal arches proliferates into numerous ridges and folds to form the tissue of the gills, which extract oxygen from the water passing between the pharynx and the watery environment.

A nearly identical process occurs to form the mouth and anus of birds, reptiles, mice, and humans. Our embryos do not start out with holes for food to enter and wastes to leave. There is a buccopharyngeal membrane between the future mouth and pharynx, and a cloacal membrane between the hindgut and the future anus. The mesenchyme, which originally separated the ectoderm and endoderm, disappears, causing the two epithelial tissues, now in direct contact, to die, creating openings through the mouth and anus to the outside world.

Life Law #4: Without intervening mesenchyme, ectoderm and endoderm come into direct contact, and without capillaries to supply blood, which reside exclusively in the mesenchyme, those epithelial layers die, leaving a hole or slit between the interior of the embryo and the outside environment.

Now to the tympanic membrane. An examination of Figure 10C will reveal that there is a considerable amount of mesenchyme between the ectoderm and endoderm of pharyngeal grooves and pouches numbers two, three and four. However, the ectoderm and endoderm of pharyngeal groove and pouch number one come very close to one another. None-the-less, the intervening mesenchyme, no matter how thin, remains in place, rich with capillaries that supply blood to the area. The first pharyngeal groove becomes the external acoustic (auditory) meatus (a passage) and the first pharyngeal pouch becomes the middle ear and auditory tube, connecting the middle ear to the pharynx. As thin as the tympanic membrane is in newborns and adults, there always remains the same three layers as in the embryo.

The world of the embryo is stranger than any strangeness we can possibly imagine. Our embryos don’t look at all like us after we are born. Rather they look much more like embryos of other animals such as lizards, chickens, and mice. Yet it is our world; a world we have all traversed; a path we have all traveled; along valleys cut by physics, genes and time into an as-yet poorly understood epigenetic landscape; and along with every creature that has ever existed or that ever will exist. This strangeness, which includes forming pharyngeal grooves that are formed and then covered up and disappear, and arteries that form and disappear almost immediately, is not only difficult to comprehend but almost impossible to explain. This nearly incomprehensible complexity led the great geneticist Theodosius Dobzhansky to exclaim “nothing in biology makes sense except in the light of evolution.”

Yet, President Nelson has spoken out in the past against evolution. In a talk given at BYU on 29 March 1987 entitled, “The Magnificence of Man,” the then Elder Russell M. Nelson stated, “Through the ages, some without scriptural understanding have tried to explain our existence by pretentious words such as ex nihilo (out of nothing). Others have deduced that, because of certain similarities between different forms of life, there has been a natural selection of the species, or organic evolution from one form to another. Many of these people have concluded that the universe began as a “big bang” that eventually resulted in the creation of our planet and life upon it.”

“To me, such theories are unbelievable! Could an explosion in a printing shop produce a dictionary? It is unthinkable! Even if it could be argued to be within a remote realm of possibility, such a dictionary could certainly not heal its own torn pages or renew its own worn corners or reproduce its own subsequent editions!”

“We are children of God, created by him and formed in his image. Recently I studied the scriptures to find how many times they testify of the divine creation of man. Looking up references that referred to create, form (or their derivatives), with either man, men, male, or female in the same verse, I found that there are at least fifty-five verses of scripture that attest to our divine creation. I have selected one to represent all the verses that convey the same conclusion:

“‘The Gods took counsel among themselves and said: Let us go down and form man in our image, after our likeness. …

“‘So the Gods went down to organize man in their own image, in the image of the Gods to form they him, male and female to form they them.’ (Abr. 4:26, 27.)”

“I believe all of those scriptures that pertain to the creation of man. But the decision to believe is a spiritual one, not made solely by an understanding of things physical, for we read that “the natural man receiveth not the things of the Spirit of God: for they are foolishness unto him: neither can he know them, because they are spiritually discerned.’ (1 Cor. 2:14)”

“It is incumbent upon each informed and spiritually attuned person to help overcome such foolishness of men who would deny divine creation or think that man simply evolved. By the Spirit, we perceive the truer and more believable wisdom of God.”

“With great conviction, I add my testimony to that of my fellow Apostle Paul, who said, ‘Know ye not that ye are the temple of God, and that the Spirit of God dwelleth in you?

“‘If any man defile the temple of God, him shall God destroy; for the temple of God is holy, which temple ye are.’ (1 Cor. 3:16, 17)

Then in a talk entitled, “Thanks Be to God,” in the April 2012 General Conference of the Church, Elder Nelson addressed the same issue, except this time, he left out the reference to evolution. He said, “Anyone who studies the workings of the human body has surely ‘seen God moving in his majesty and power.’ (Doctrine and Covenants 88:47) Because the body is governed by divine law, any healing comes by obedience to the law upon which that blessing is predicated. (See Doctrine and Covenants 130:21)

“Yet some people erroneously think that these marvelous physical attributes happened by chance or resulted from a big bang somewhere. Ask yourself, ‘Could an explosion in a printing shop produce a dictionary?’ The likelihood is most remote. But if so, it could never heal its own torn pages or reproduce its own newer editions!”

Pondering these two talks, it is my opinion that it is the apparent, perceived stochastic nature of the Big Bang and evolution with which President Nelson disagrees. Again, here President Nelson references “divine law.” I, personally, believe that we who study science should search for divine law in all aspects of our existence. In this essay, I have pointed out some of what I think are divine laws governing the development of the embryonic pharynx and the auditory structures.

If we follow the valley of pharyngeal arch development back up the epigenetic slope, that path apparently points back in time to the first appearance on earth of a pharyngeal apparatus. In our path back in time to discover the origins of pharyngeal structures, we encounter two remarkable “living fossils.” One is an agnatha (a jawless fish) called a lamprey (Figure 12), the most primitive extant vertebrate, and the most structurally primitive animal to possess pharyngeal arches. The earliest fossil lampreys date from the Upper Ordovician – around 450 million years ago.

Figure 12. The lamprey Lampetra fluviatilis in Pirita river, Estonia.

The second living fossil is a lancelet (Figure 13; also called an amphioxus), an invertebrate Cephalochordate with pharyngeal segmentation and gill slits in the head. The gill-slits are used for taking in small food particles, and not for respiration. Respiration occurs directly through the skin, which is a simple epithelium. A single blind caecum, branches off from the gut, with an epithelium that phagocytizes the food particles taken in through the gills. Although the cecum performs many functions of the vertebrate liver, it is not considered to be a true liver. Lancelets also have a closed circulatory system with a primitive heart-like pumping organ. The circulation transports digested food particles throughout the body, but does not have red blood cells or hemoglobin for transporting oxygen.

Figure 13. A Lancelet (or Amphioxus) specimen —Subphylum: Cephalochordata— collected in coarse sand sediments (600 µm) on the Belgian continental shelf. Total Length: approximately 22 mm. Hans Hillewaert; 1997, QS:P571,+1997-00-00T00:00:00Z/9

As is the case in other invertebrates, lancelets have a single cluster of Hox genes rather than the multiple copies found in vertebrates. However, the sequence of lancelet genes is very similar to that of vertebrates and Hox gene expression patterns reveal homologous axial positions between lancelet and vertebrate embryos. For example, the Hox pattern in the vertebrate hindbrain is homologous to an extensive region of the lancelet neural tube.

Lancelets resemble and have been proposed to be closely related to, the 530-million-year-old Pikaia, from the Cambrian, whose fossils have been extracted from the Burgess Shale.

Figure 14. Life reconstruction of Pikaia gracilens

In my recent book The Infinite Creation (Stephens, Trent, Cedar Fort, 2020) I stated:

“One of the less common members of the [Burgess shale] community, and not at all impressive, was the little, two-inch-long fish-like animal named Pikaia.26 Although, even now, there are millions of arthropods in the oceans and on land, the tiny, unimpressive Pikaia, and its kin, were destined to give rise to the vertebrates, which would eventually dominate the Earth. Pikaia probably swam much like an eel and may have developed one of the first heads among the animals leading to the vertebrates. It had two antennae and six pairs of gill-like appendages. It also possessed a notochord and exhibited some thirty eight V-shaped muscular body segments.”

“First discovered by Charles Walcott in the famous Burgess Shale there has been much debate about Pikaia's taxonomic classification – in particular its relationship to the vertebrate clade. Once thought to be the oldest known chordate - the direct ancestor of all vertebrates - Pikaia is now considered to belong to a stem group of basal chordates that included the ancestors of modern vertebrates. Even if Pikaia is not the direct ancestor of modern vertebrates a creature with many of the same anatomical features almost certainly was.”

“Pikaia's most defining feature is the putative notochord that runs along the head-tail axis of its body. The notochord is a rod-like flexible organ that, among other roles, acts as an anchor for muscles within an organism which in turn facilitates movement. Over many generations the notochord was to become encased within the calcified bones of a vertebral column – the defining feature of all vertebrates.”

Again, I quote from my book, The Infinite Creation: “This ‘cosmopolitan’ distribution of several fish-like animals at the time of the Burgess Shale belies [Stephen Jay] Gould’s conclusion in Wonderful Life (literally the last page), ‘Wind the tape of life back to Burgess times, and let it play again. If Pikaia does not survive in the replay, we are wiped out of future history – all of us, from the shark to robin to orangutan…And so, if you wish to ask the question of the ages – why do humans exist? – a major part of the answer…must be: because Pikaia survived the Burgess decimation. This response does not cite a single law of nature; it embodies no statement about predictable evolutionary pathways, no calculation of probabilities based on general rules of anatomy or ecology. The survival of Pikaia was a contingency of “just history.”…We are the offspring of history…’2

“Herein, Gould mentions and promptly dismisses a “law of nature” to explain vertebrate evolution and the origin of humans, but then claims, unequivocally that we are “the offspring of history” – this sounds a lot like stamp collecting, not science. Conversely, I propose there were laws of nature governing the course of evolution – we simply haven’t, as yet, given enough effort and creativity to fine them.

“For example, one rule of evolution might be that having a head may be an advantage to literally getting ahead in the evolution contest. Head formation in early animals has been proposed to have resulted from an elongated body, active swimming in search of food, and a mouth at the leading end. The search for food meant sensing the environment – such as smelling, feeling, and seeing – near the mouth. Concentration of nerves in the area of those sensory organs and nerve interactions for processing and responding to sensory information began the pathway toward a brain.30”

Furthermore: “Gould challenged anyone reading the Wonderful Life to consider, “I must be able to convince you – by actual example – that honorable, reasonable, and fascinating different alternatives could have produced a substantially divergent history of life not graced by human intelligence.”2 The “reasonable,” “actual example” Gould came up with was a contest between polychaetes (segmented, marine bristle worms) and priapulids (unsegmented, smooth marine worms). Whereas both began in the Burgess Shale era, priapulids had the numerical advantage. However, polychaetes won out in the long run, having some eight thousand extant species today and priapulids lost, having only fifteen extant species. Gould claimed that, “For some reason, priapulids do not rank among the success stories of modern biology.”2 He continued, “The entire modern world contains scarcely more genera of priapulids than the single Burgess fauna from one quarry in British Columbia…Burgess priapulids occupied center stage…What happened? We do not know. It is tempting to argue that polychaetes had some biological leverage…But we have no idea what such an advantage might be.”2 How about polychaetes having heads and priapulids lacking the same? Would that make any difference? Is there a law of evolution that says “If you have a head you have a great advantage over something without a head”? I’ll take that challenge, Stephen, and I think your history hypothesis is losing out to laws of science.

“Concerning priapulids, marine biologist Ronald Shimek stated, “…these animals really don't have a defined head.”36 Furthermore, based upon genetic data, polychaetes exhibit a complete head to tail complement of Hox genes (developmental patterning genes, which will be discussed more in a later chapter), whereas priapulids show only caudal (tail) Hox genes – they exhibit no complete Hox gene sequences in what would be the head, if they had a head – which they do not.37”

The sequence of nucleotides in Hox genes is not random. The process of mutation is more or less random, however, given an almost infinite number of mutations in the history of DNA on this or any other planet, the combination of 180 nucleotide bases forming the homeobox is inevitable. The 180 nucleotide bases in the homeobox code for 60 amino acids that form what is called the homeodomain. Those sixty amino acids supercoil to form a structure that fits very precisely into the major and minor grooves of DNA and then regulates gene expression.

Figure 15. The Antennapedia homeodomain protein from Drosophila melanogaster bound to a DNA fragment, illustrating the binding interactions of the recognition helix and unstructured N-terminus with the DNA major and minor grooves. Homeodomain-dna-1ahd.png; GFDL

Life Law #5: DNA is the inevitable life-giving molecule in the universe. No matter what other chemical combinations arise, be they lipid, protein, RNA, or DNA; DNA will always become the supreme repository of living information that can be stored and passed on from one cell to another and to the infinite offspring of those cells. Any protein that interacts with DNA in order to control is gene expression, will have a structure identical to or nearly identical to the homeodomain.

As we progress up the valleys of the epigenetic and hypogenetic landscapes, and search for more and more laws of life that govern the earliest and subsequent laws of development, we will discover that the process is not a stochastic, random walk through time, but rather, the unfolding of ever more complex laws that govern ever more complex morphologies. We will ultimately discover that by means of those life laws, we human beings are indeed created in the image of an omniscient, omnipotent God – our Heavenly Father.

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