A scientific and philosophical assessment of supposed "poor design" examples in the natural realm
by Casey Luskin
One of the most common objections to intelligent design theory is the claim that if certain aspects of the biological realm function at a level below the most optimal energetic level of efficiency, and thus they could not have been designed. Because this objection is theological in nature, only a theological answer can be given in response. Such arguments rest upon two major assumptions:
• That the existence of such "sub-optimal" functions necessarily implies that they were not designed.
The most famous alleged examples of "bad design" are expounded by Richard Dawkins in "The Blind Watchmaker" and Stephen Jay Gould in "The Panda’s Thumb". Dawkins believes that the vertebrate eye is wired "backwards" and gives the appearance of random evolutionary wiring, rather than the optimal design (who Dawkins thinks acts and thinks with the purposes of modern-day engineers) would give it. According to Dawkins, "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!)"1.
Dawkins claims that the fact that the neural layer sits over the eye is evidence of poor design for it inhibits vision, however, this fact results in an insignificant reduction of vision8 (as even Dawkins admits) which never gets noticed unless you are doing that old trick where you close one eye and stare at a dot until it disappears (due to the location of the optic nerve). In fact, the presence of the neural layer in front of the photo receptor cells actually prevents over-bleaching of the receptor pigments, which would incapacitate the visual apparatus8. Furthemore, it turns out that vertebrate eyesight is actually so advanced that the eye requires a very large supply of blood in order to provide high levels of visual information to the brain. In order to keep fresh blood flowing to the photo-receptor cells in the retina, it is necessary that each cell be directly plugged into blood capillaries from the rear. As a result, the only way for it to reach its level of functionality is to have the optical nerve extend out over the retina.2 If the vertebrate eye were arranged the other way as Dawkins suggested, "these two opaque layers [the neural layer and the blood capillaries] would have to be interposed in the path of light to the photoreceptors which would leave them in darkness!!"8. In other words, if Dawkin's had been our intelligent designer, the eye wouldn't function at all.
Stephen Jay Gould argues that the "thumb" of the Panda (which really consists of uniquely modified wrist bones) functions much worse for grasping objects, such as bamboo shoots, than does the true opposable thumb found in humans and therefore Gould says it has poor design. This poor design is not the work of a designer but rather the result of an unfortunate set of mutations plagueing the panda.
As it turns out, however, the human opposable thumb is not at all well designed to accommodate 12 hours/day of scraping leaves from bamboo branches (which is what Pandas do) however the panda's thumb can accomplish this function without a problem. A recent study used MRI and computer tomography analyzed the panda thumb and concluded the following:
These writers (Gould and Dawkins) are at least doing a better job of putting intelligent design on the table than anyone else, however their arguments rely upon theological assumptions about how the designer ought to operate (i.e. a theology) which are suspect, so that their critiques hardly give the issue a fair treatment. As Phillip Johnson writes,
While maximum energetic efficiency is a goal of many race-car designers, it is not necessarily the singular design specification of an infinitely wise and perfect Being who has many complex purposes and plans for His creation (perhaps such as, say, the permanent conquering and destruction of evil). Anyone who claims sub-optimal design must be prepared to give up that belief if future studies show that a broader look at the situation actually reveal that the system is not sub-optimally designed; Gould would most likely re-think his Panda’s thumb arguments before re-using them today. Accordingly, true sub-optimalities can never be proven, for one never knows that there isn’t a higher level of order in which the apparent sub-optimality is actually perfectly fulfilling the exact function it was intended to perform.
This issue has now essentially boiled down to the age-old objection to JudeoChristian theology known as the "problem-of-evil" argument. The argument states that a kind, loving, all-powerful God cannot coexist with evil. To apply this to ID, they are saying that a designer would not create something with energetic suboptimality. Since we are speaking in a theological context where they assume the designer is God, then it is fair to point out that their theological objection not only assumes that the evil must be the sole responsibility of God, but it denies the need for and meaning of free will and assumes there could not some higher purpose for which God has allowed for the evil (sub-optimalities) to currently exist!
A classic example of this flawed reasoning can be seen in the writings of Charles Darwin himself:
This case also illustrates the thought processes behind such arguments: in saying what God can and cannot do he is putting his own wisdom and reasoning above God’s. In Darwin’s mind, it would have been impossible for God to have made things the way Darwin saw them. Does this mean that Darwin sees things correctly? The key words here are "the way Darwin saw them" for Darwin claims that his own reasoning powers and knowledge set are sufficient to exclude the possibility that God could have created the Ichneumonidae. As God says to Job, "Where were you when the foundations of the earth were laid?" (Job 38:4). Where was Darwin when God designed the ecosystem? Does Darwin have a large enough knowledge set to make qualified judgments about these issues? If in fact our knowledge set is limited when compared to that of the Creator of the universe, or even when compared to what we think is out there in the natural world, perhaps we ought to reserve judgment until we have a complete and accurate physical and metaphysical picture of what’s really going on in the world.
People may falsly trust their own reasoning and knowledge set, however, I do not mean to brush aside all examples of evil, sub-optimalities, and suffering by lightly responding that they all simply have a greater good purpose which may or may not be understandable at this time. No, this ultimately is not the proper response. Sadly, for us all, evil and sub-optimalities are real—they are here today. It would be naive, foolish, destructive, and irresponsible to pretend that we live in a perfect world masquerading as an imperfect one. However, from the standpoint of the evolutionist looking at evil and saying—"look, you say your good God did this!", it must be recognized that the Bible had had an adequate answer for why there is evil and imperfection for thousands of years previous. Thus, there can be given a theological answer to this theological objection.
The text of Genesis states that in the beginning God when created everything, it was "good" (Genesis 1:31). Now I’m not sure what exactly what "good" means, but it doesn’t necessarily mean "perfect" in the sense that all was necessarily free from all forms of sub-optimalities. Now the skeptic right here would throw in the point that "Couldn’t an all knowing God know how to create the world without these sub-optimalities?". The answer is Yes, He does know how to create a "perfect" world, but He chose not to. And He didn’t choose not to because He didn’t love us, but rather because He does love us (more on this later)! Most JudeoChristian theologians agree that Genesis admits that suffering and evil are ultimately the result of humanity’s freely chosen rebellion (sin) against God. Free will in the moral sense is the ability to freely choose what is right and wrong. Since relationships can only be real and have true love if there is free choice involved, and since God wants to have real loving relationships with humans, God gave us free will. Thus God gives us the choice to choose what is right (God, love, selflessness) or what is wrong (hatred of God, selfishness, evil) so our relationship to Him can be real. To summarize, evil doesn’t have to exist in this world, but the opportunity to choose it must exist if the relationship is to be real (and we're not just robots). Unfortnately, we collectively have chosen evil and suffering and sub-optimalities have entered the world as a result. The result is what we call a fallen world full of imperfection.
The arguments used by Dawkins and Gould are grounded in the assumption that God must have created everything in this universe in a "perfect" fashion, and that everything must have been created with 100% unhindered energetic efficiency--All the power and none of the pain! Biblical theology predicts that in a fallen universe full of self-chosen evil, imperfection will be found. Thus Gould’s and Dawkins’s alleged sub-optimality arguments, even if valid, hardly make a dent in Biblical theology. Running straight to the Biblical theologian saying "see, look, I found imperfection!" would usually evoke a cool-headed response saying "Duh, like we didn’t already know it was there, it's the result of sin! But why are you so worried? God has it all under control." The true root of the evolutionist’s objection is revealed as the refusal to acknowledge that imperfection might not be God's fault, and that God be actually be able have it all under control (He is, after all, God). Accepting either of those premises is an inherently spiritually humbling act that not all of us are always willing to perform. It is this refusal, coupled with an unwillingness to accept the clear and unavoidable limits to our metaphysical knowledge that spawn arguments like those of Dawkins and Gould.
Though Genesis teaches that imperfections persist in the world because of sin, Biblical theology also teaches that although these imperfections exist today, God is mercifully in the process of destroying evil and ending this imperfection once and for all. We are extended a life-raft—salvation through the atoning death Jesus Christ--to get out of this ocean of imperfection. If we choose to grab hold on to it, we are saved from all ultimate lasting effects of the imperfection and evil of this world. Since our sin is the cause of evil in this world, God requires its death. However, because He loves us, He sent His Son, Jesus Christ, to die in the world’s place, to show us He loves us, and simultaneously to remove the ultimate effects our sin from our lives, effectively conquering evil. Christian theology teaches in John 3:16 that, "God so loved the world that he gave his one and only Son, that whoever believes in him shall not perish but have eternal life." All one has to do is believe in Jesus as savior from sin and evil, and we will be saved from this evil. We got ourselves into this mess, and God wants to pulls us out. Since our relationship to Him must be real, our getting pulled out ultimately requires a choice on our part to believe that He will pull us out and then ask Him to do so.
God promises to one day re-create the universe in a more perfect form perhaps not totally unlike the 100% energetic-efficiency world hoped for by Dawkins and Gould. Since evil exists before the creation of the universe (due to the rebellion of various spiritual beings against God), and doesn’t afterwards, it appears that something about this universe has something to do with something relating to the ultimate and complete destruction of evil. If this is the case, then perhaps all of these apparent sub-optimalities in biological design really are designed to perfectly fulfill their intended purpose: namely, to be a cog in the machine of the universe, a tool, in part, playing a perfectly designed role in God’s plan for the ultimate and complete destruction of evil.
This is such an important and also complex issue that it comes up time and time again on the IDEA Club debate listserve (if you’d like to join the debate listserve, just come to a meeting, become a member, and we’ll get you signed on to it). However, the author feels that this is such an important issue that if you’d just like to discuss it further, he’s willing to take anyone who sees evil as a big wall between themselves and their only ticket out of evil (belief in God’s salvation) to lunch! So, if you’ve got questions, comments, gripes, or issues with God and evil and you want a free lunch, e-mail the author at "firstname.lastname@example.org". Evil is something we are all struggle through and try to explain, and thus it is something worth hearing each other’s perspectives over. Perhaps by going to lunch you’ll gain a new and different perspective!
A Final Afterthought
Gould’s and Dawkins’ arguments do raise a final interesting point about the implications of the actual existence of such sub-optimal designs. If sub-optimally-performing organisms are out-competed, then over time we should see sub-optimalities tend to disappear. Any sub-optimally functioning features ought to be either selected out or improved upon, if there is selection pressure against the sub-optimal feature. If evolutionary forces are the only ones at work, the presence of sub-optimal designs implies that things tend to get stuck on adaptive peaks and cannot naturally evolve further—a prediction of arguments for irreducible complexity. What initially appeared to be an argument against intelligent design might equally become an argument against an evolution history—especially if the supposed sub-optimalities have supposedly persisted for millions of generations admits selection pressure.
The evolutionist is now in a self-contradictory position, for persistent sub-optimalities imply a limitation to the natural creative power of evolution—something evolutionists desperately disavow. If imperfections do persist, then according to the way evolution, by definition, works, they must not be truly sub-optimal features. Thus, to the evolutionist, sub-optimal designs ought to make them turn their heads and say, "wait a second, I put all that faith in natural selection and it goes on to produce this awkward useless feature?" However, if intelligent design is involved, then theology is no longer excluded from the explanatory grab-bag, and a whole new door of potentially fruitful explanations for the origin of alleged sub-optimalities is opened.
Theistic models of intelligent design define optimality as that which matches God’s purpose, which is ultimately loving and wise. Nothing should exist which isn’t in concert with that purpose, or a result of the actions and interactions of good or evil forces within the metaphysics of that model. Positively arguing against a theistic ID model through sub-optimal design requires a correct metaphysic, understanding of theology, and a bigger knowledge set than humans have at the present time. In essence, it is very difficult, if not impossible to prove a sub-optimality under a theistic worldview. While scientists don’t like unfalsifiable models, this argument only shows that one particular objection to intelligent design can't be fruitful; other objections still may be proveable. Regardless, I think that those who object and say that intelligent design ought to be falsifiable in this manner have completely forgotten about the limitations of humans next to God's omnipotence and awesome mighty power. Objecting to intelligent design in this form means denying God's unlimited power and wisdom in the first place.
In a final explanation of the title of this paper, we see that the evolutionists have not employed good theology and found bad design, but rather they have employed bad (or perhaps misguided) theology and we have seen examples of very good design. However, even if bad design were one day detected, this would in no way challenge a Biblical picture of the design of the world. If you disagree with my last statement, I highly ask that you take me up on that lunch offer (but I get to pick the restaurant!).
1. Dawkins, Richard (1986). The Blind Watchmaker. London: Penguin Books; pp. 93-94
2. Denton, Michael, "The Inverted Retina: Maladaptation or Pre-adaptation?" Origins & Design (19:2) Issue 37. (Also available at http://www.arn.org/docs/odesign/od192/ir192summ.htm#anchor4039228
3. Hideki Endo; Daishiro Yamagiwa; Yoshihiro Hayashi; Hiroshi Koie; Yoshiki Yamaya; Junpei Kimura; Role of the giant panda’s pseudo-thumb. Nature, January 28, 1999, Vol 347 # 6717 Pg. 309-310.
4. Phillip Johnson. Reason in the Balance, InterVarsity Press (1995), Pg. 90.
5. Darwin C., letter to Asa Gray, May 22, 1860, in Darwin F., ed., "The Life of Charles Darwin," , Senate: London, 1995, reprint, p.236
6. Encyclopaedia Brittanica’s entry on "Ichneumon". Can be found at: http://www.britannica.com/bcom/eb/article/4/0,5716,42934+1+41986,00.html.
7. Edward E. Farmer. Plant Biology: New Fatty Acid-Based Signals: A Lesson from the Plant World. Science, Volume 276, Number 5314, Issue of 9 May 1997, pp. 912-913.
8. Peter W. V. Gurney. Is Our ‘Inverted’ Retina Really ‘Bad Design’?, Creation Ex Nihilo Technical Journal, Vol. 13, No. 1, (also available at http://www.trueorigin.org/retina.htm)
9. The author would also like to thank the conversations, insight, and information provided by Richard Deem (via e-mail), Stephen C. Meyer (via e-mail), and Fuz Rana (from his lecture at Reasons to Believe's "Putting Creation to the Test Conference", June 22-24, 2000) which greatly aided in the production of this document.