Examples
of Bad Design Gone BadA refutation of "bad design" in nature claims
by Rich Deem
Examples
of Bad Design Gone Bad|
Bad Design in Nature? |
| Evolutionists often complain about "bad" designs in biology. The hypothesis is that evolution will often improvise and make bad, jerry-rigged designs because of physical limitations placed on the system by biology, physics or chemistry. In essence, evolutionists say that they can do better. The implication is that a divine designer could not do such a poor job. Let's look at some famous examples of "bad design" and see what the latest published literature says about that design. |
In a recent article in Scientific American entitled "If Humans Were Built to Last,"1 evolutionists S. Jay Olshansky, Bruce Carnes, and Robert Butler argued that the human body reflects the mindless process of natural selection, and not intelligent design. The authors said that many of our physical shortcomings exist because natural selection causes us to survive "just long enough to reproduce." Once we've passed on our genes, they say, our bodies start to fall apart, since natural selection no longer operates.
One of the examples of "bad design" proposed by Olshansky et al. is the human esophagus. At the bottom of the throat, the trachea (the passage that leads to the lungs) enter the esophagus. When you swallow food or water, a structure called the epiglottis closes to cover your trachea so that these materials do not go into your lungs. The system does not work perfectly every time, as we have all experienced when choking on food or water that "goes down the wrong way." In some instances, this choking can be life threatening. Olshansky et al. suggest that a better design would be to have two separate tubes - one leading from the nose directly into the lungs and the second leading from the mouth directly to the stomach.
There are several problems with this "better" design. First, to have two tubes in the neck would require extra space and extra systems (with the associated additional energy costs) to maintain two structures. More importantly, it would be very difficult to breathe when you get a sinus infection. Congestion in the nose would be life threatening, since it would prevent or severely restrict breathing, since the nose would be the only way that air could enter the lungs. There would also be the problem of getting rid of liquid that accidentally enters the lungs. It would have to be pushed all the way up to the nose and expelled there (make sure you carry lots of tissue with you!). Under the current system, it need only go to the top of the trachea and the down the esophagus to the stomach. The two tube design would also restrict the amount of physical activity that humans could do. When we run, we take in air through our mouths, since the larger opening allows for a more rapid respiration rate. The only way to allow for a large respiration rate with one tube to the nose would be to greatly increase the size and openings in our nose. Not only would this look ugly, but the larger openings would present problems. Things could enter into such large openings and have direct access to your lungs (How would you like to inhale a fly into your lungs?). Larger nasal passages would also reduce the temperature of the air, since it could not be heated as effectively (important for cold climates). Another major problem would be speech and language. We need to use our mouths and tongue in order to produce speech. Air running over vocal cords, in the absence of a tongue, lips and teeth, would only be able to produce a very limited number of sounds (it might not affect Rambo, but the rest of us would have a difficult time communicating). Try it some time (hold your mouth open and don't move your tongue as you attempt to communicate). Of course the evolutionist might propose additional structures in the nose (like a tongue, lips and teeth-like structures).
So, here is what the evolutionists are proposing for a superior breathing apparatus. Our trachea would continue up to our nose, requiring our necks to be at least 1 inch wider. We would have huge noses with nose lips and a tongue protruding out. Of course, our faces would have to be much longer to accommodate the additional structures. Now, we would really be ugly! On second thought, it might be interesting trying to kiss with two sets of lips - nah, constantly expelling liquid out our nose would make it kind of gross. Aren't you glad you weren't designed by an evolutionist!
A new study analyzed the giant panda's thumb using computed tomography, magnetic resonance imaging (MRI) and related techniques. Contrary to what evolutionists have previously expressed about the "bad design," the current study shows that the radial sesamoid bone (its "thumb") is "one of the most extraordinary manipulation systems" among mammals.2
The radial sesamoid bone functions as an active manipulator, enabling the Panda to grasp bamboo stems between the bone and the opposing palm. Contrary to previously published studies, a computerized analysis of the three-dimensional images indicate that the radial sesamoid bone does not move independently of its articulated bones, but acts as part of a functional unit of manipulation. The radial sesamoid bone and the accessory carpal bone form a double pincer-like apparatus enabling the panda to manipulate objects with great dexterity.
A
schematic animated model based on the recent study is shown at right. The model
shows how the metacarpals, radial sesamoid and radial carpal bones function as a
unit to grasp objects. The accessory carpal acts as an additional
"finger" when the hand grasps food. The abductor pollicis brevis,
opponens pollicis, and abductor digiti quinti muscles further serve in grasping
when contracted during grasping.
Evolutionists say that the design of the Panda's thumb is bad compared to that of the primate opposable thumb. However, the opposable thumb is not designed for continuous grasping. Such kind of usage can result in carpal tunnel syndrome (just ask any laboratory technician who has been pipetting for many years). Being a herbivore, the Giant Panda spends nearly all of its waking hours eating. It collects bamboo leaves by grasping and stripping leaves from the stalks. Contrary to what the evolutionists say, the opposable thumb would be a bad design for the Panda, since it could not function under the stress of continuous use. The Panda's hand, with its "thumb" bound to the metacarpals, is a much stronger design able to withstand continuous use.
The authors concluded their study with the following statement:
"We have shown that the hand of the giant panda has a much more refined grasping mechanism than has been suggested in previous morphological models."
The vertebrate eye is
quite an exceptional organ in terms of its function. Light passes through the
cornea, then through the lens where it is focused on the retina, which contains
the photoreceptors (rods and cones) for detecting this light (see diagram to
right). Each rod and cone that receives light fires a signal to the neural
apparatus, which transmits the signal to the optic nerve, which goes to the
brain for processing. The brain does some fancy processing, including inverting
the image and interpreting what is seen (this is a whole other story that cannot
be covered here).
The invertebrate eye is much simpler and is quite different, especially in the design of its retina. The invertebrate retina is composed of the photoreceptors, which face the incoming light, followed by the neural layer, and the underlying layers that supply nutrients and oxygen through a capillary bed. However, the vertebrate retina is said to be "inverted," since the neural layers face the light and the photoreceptor cells actually face away from the incident light. Evolutionists say that this arrangement was the result of improvised evolution in which obvious errors in "design" were accommodated through successive mutational alterations to make the apparatus work in a functional manner. According to Richard Dawkins, a leading proponent of evolution:
"Any engineer would naturally assume that the photocells would point towards the light, with their wires leading backwards towards the brain. He would laugh at any suggestion that the photocells might point away, from the light, with their wires departing on the side nearest the light. Yet this is exactly what happens in all vertebrate retinas. Each photocell is, in effect, wired in backwards, with its wire sticking out on the side nearest the light. The wire has to travel over the surface of the retina to a point where it dives through a hole in the retina (the so-called ‘blind spot’) to join the optic nerve. This means that the light, instead of being granted an unrestricted passage to the photocells, has to pass through a forest of connecting wires, presumably suffering at least some attenuation and distortion (actually, probably not much but, still, it is the principle of the thing that would offend any tidy-minded engineer). I don’t know the exact explanation for this strange state of affairs. The relevant period of evolution is so long ago."3
Dawkins doesn't know why the vertebrate retina is designed this way because he doesn't really understand how the eye works. In fact, the retina is designed with slightly suboptimal light gathering abilities so that it will be functional for at least several decades. If it were designed according to Dawkins' "tidy-minded engineer," it would not work at all, as we shall see.
First, we need a short introduction to the physics of light. The electromagnetic spectrum emitted by the sun is composed of many different wavelengths, a small percentage of which are visible to our eyes (370-730 nanometers). The near-visible wavelengths include the longer wavelengths (infrared) and the shorter wavelengths (ultraviolet). The amount of energy within each wavelength is inversely proportional to the wavelength. Therefore, electromagnetic energy that consists of shorter wavelengths (e.g., ultraviolet light) is more energetic.
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| Neural Layer |
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| Rods and Cones |
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| RPE Choroid |
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on animation to enlarge (444 KB) |
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Although the visual apparatus cannot detect the high energy wavelengths, it is still affected by them, since the entire system is exposed to the full spectrum. In contrast, the rest of the body is protected from high energy light by pigment (melanin) in the skin. Even so, a lifetime exposure of the skin cells to this light can result in DNA damage, which may lead to the development of cancers. The eye contains a special layer of cells, the Retinal Pigment Epithelium (RPE), which has complex mechanisms for dealing with toxic molecules and free radicals produced by the action of light. Specific enzymes such as the superoxide dismutases, catalases, and peroxidases are present to eliminate potentially harmful molecules such as superoxide and hydrogen peroxide. Antioxidants such as a-tocopherol (vitamin E) and ascorbic acid (vitamin C) are available to reduce oxidative damage.
Because of continuous damage caused by light, the discs (along with the photopigments) of the photoreceptor cells are continuously replaced by the RPE.4, 5 If this were not the case, the photoreceptors would quickly accumulate fatal defects that would prohibit their function. In addition, the RPE cells contain the pigment melanin, which absorbs stray and scattered light to improve visual acuity. The RPE is in contact with the choroid layer, which contains a very large capillary bed, which has the largest blood flow per gram of any tissue in the body. Why is the blood flow so high in the choroid? Since the RPE and photoreceptor cells are in constant regeneration, they require a high rate of exchange of oxygen and nutrients. In addition, it appears that the high rate of blood flow is required to remove heat from the retina to prevent damage resulting from focused light (the old magnifying glass in the Sun phenomenon).6
So why is Dawkins' "tidy-minded engineer" design such a bad idea? Dawkins thinks that the neural layer should be under the photoreceptors, putting them between the photoreceptors and the choroid. Where would the RPE (which is required to regenerate the photoreceptors) go? If it were between the neural layer and the choroid, it would be too far away from the photoreceptors to constantly regenerate them. In addition, this design would put another layer between the photoreceptors and their blood supply, reducing the exchange of oxygen and nutrients, and minimizing the effectiveness of the choroid in removing heat from the receptors. Dawkins' idea of "good" evolution would prevent the photoreceptors from being regenerated and would likely lead to heat damage. Such a design would certainly fail within the first year of use. It's a good thing that God does not design the way evolutionists would!
More information on the design of the eye can be found at the links below.7-9
Another common "vestigial" organ, according to many uninformed atheists is the human appendix. Since food does not flow through it, like the rest of the intestine, the assumption is that it has no function. It certainly does not have digestive function. This is true. However, the intestine is much more than just a digestive organ. An examination of the appendix microscopically, shows that it contains a significant amount of lymphoid tissue. Similar aggregates of lymphoid tissue (known as gut-associated lymphoid tissues, GALT) occur in other areas of the gastrointestinal system. The GALT are involved in the body’s ability to recognize foreign antigens in ingested material. My own research, in particular, is focused on examining the immunological functions of the intestine.
Experiments in rabbits demonstrate that neonatal appendectomy impairs the development of mucosal immunity.10 Morphological and functional studies of the rabbit appendix indicate that it is probably the equivalent of the avian bursa in mammals.11 The bursa plays a critical role in the development of humoral immunity in birds. The histological and immunohistochemical similarity of the rabbit and human appendix suggest that the human appendix has a similar function to that of the rabbit appendix. The human appendix may be particularly important early in life because it achieves its greatest development shortly after birth and then regresses with age, eventually resembling such other regions of GALT as the Peyer’s patches in the small intestine. These recent studies demonstrate that the human appendix is not a vestigial organ, as originally claimed.
According to Dr. Moore (Clinically Oriented Anatomy), "in infants and children it has the appearance of a well-developed lymphoid organ and may have important immunological functions."
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The existence of large amounts of non-coding DNA (up to 97% in humans) in the
genomes of eukaryotes has been used as an argument against intelligent design
(and the role of a Creator) and as an argument for the random process of
evolution. However, a recent study13 has shown that
eukaryotic non-coding DNA (also called "secondary DNA") is functional
as a structural element in the nucleus. Previously, there were two evolutionary
theories that attempted to describe the reason for the existence of non-coding
DNA One theory stated that non-coding DNA was "junk" that consisted of
randomly-produced sequences that had lost their coding ability or partially
duplicated genes that were non-functional. The second theory stated that
non-coding DNA was "selfish", in that it consisted of DNA that
preferentially replicated more efficiently that coding DNA, even though it
provided no selective advantage (in fact was somewhat detrimental in that it was
parasitic).
The new study examined the genomes of the single-celled photosynthetic organisms
know as Crytomonads. These organisms exist as vastly different cell sizes, with
the nucleus being proportional in size to that of the cell. Researchers
discovered that the amount of non-coding DNA was proportional to the size of the
nucleus, suggesting that more non-coding DNA was required in larger nuclei. As
an added proof, the nucleomorph, a small piece of DNA contained within the
plastid that codes for itself and photosynthetic function, was not changed in
size, despite changes in cell size and nuclear content.
The new study is a stunning rebuttal to the evolutionary theories that attempt
to discredit design and promote concepts such as "junk" DNA and
"selfish" DNA. According to the authors:
"Furthermore, the present lack of significant amounts of nucleomorph secondary DNA confirms that selection can readily eliminate functionless nuclear DNA, refuting 'selfish' and 'junk' theories of secondary DNA"
Related Story - "When 'Junk' DNA Isn't Junk"
Kennon Guerry, R., Ham, W.T., Mueller, H.A. 1998. Light toxicity in the posterior segment. In Tasman W., Jaeger EA. (eds.), Clinical Ophthalmology, Lippincott-Raven, New York, vol. 3, ch. 37.
Young, R.W. 1982. The Bowman Lecture: Biological renewal: Applications to the eye. Trans. Ophthalmol. Soc. UK 102 :42-67.
Parver, L.M., Auker, C., Carpenter, D.O. 1980. Choroidal blood flow as a heat dissipating mechanism in the macula. Am. J. Ophthalmol. 89:641–646.
