The Christadelphian magazine and evolution. Part 3 - John Hellawell

The April 2015 edition of The Christadelphian carries an article by freshwater ecologist John Hellawell, which like the previous two attacks on evolutionary biology fails to differentiate between evolution as fact and evolution as theory, which means its argument is ultimately aimed at a straw man version of evolution. Further undermining its credibility is its invocation of long-rebutted special creationist arguments such as 'survival of the fittest' being a tautology. It also makes attacks which are readily dismissed by anyone with a grasp of developmental biology and population genetics. Finally, it invokes the tired 'halting between two opinions' trope in which the author pits evolution against creation, a strategy which will simply help catalyse a loss of faith in those who have been inculcated with this false dilemma. Those who have been told that our faith is based on evolution being false are hardly to be blamed for abandoning us when they discover that contrary to what Hellawell and others assert, the evidence for evolution is beyond dispute.

Opponents of evolution in our community often assert that evolution enjoys support in the scientific community primarily on anti-theistic grounds, and is in reality a ‘theory in crisis’, with no evidence to support it. The former is demonstrably false, as I have repeatedly pointed out. At least two of the leading figures in the modern evolutionary synthesis – Theodosius Dobzhansky [1] and Ronald Fisher – were devout Christians, while today, scientists of the caliber of Simon Conway Morris (palaeontology) and Kenneth Miller (cell biology) are representative of the majority of Christians who work in the life and earth sciences and accept the reality of evolution. [2] Respected organisations such as BioLogos, the American Scientific Affiliation, Christians in Science, and the Faraday Institute for Science and Religion provide reasoned defences of both evolutionary biology and Christianity from highly respected biologists and Biblical scholars. To argue that evolution and atheism are synonymous is to fall into the trap maintained by both the fundamentalist fringe of Christianity, and the anti-theist zealots from the New Atheist movement.

The assertion that evolution is a 'theory in crisis' is frankly risible, if only because those who attack evolution Allan Harrison and Robert Talbot demonstrated in their articles in The Christadelphian cannot even properly define evolution, let alone provide a coherent, informed criticism of it. As the respected evolutionary biologist Douglas Futuyma points out:

In The Origin of Species, Darwin propounded two major hypotheses: that organisms have descended, with modification, from common ancestors; and that the chief cause of modification is natural selection acting on hereditary variation. Darwin provided abundant evidence for descent with modification, and hundreds of thousands of observations from paleontology, geographic distributions of species, comparative anatomy, embryology, genetics, biochemistry, and molecular biology have confirmed this hypothesis since Darwin's time. Thus, the hypothesis of descent with modification from common ancestors has long had the status of a scientific fact. [3]

Futuyma is hardly alone. Evolutionary biologiost Ryan Gregory likewise shares Futuyma's assessment of the overwhelming nature of the evidence for common descent when he remarks:

Over the past 150 years, this initial list has been supplemented by countless observations in paleontology, comparative anatomy, developmental biology, molecular biology, and (most recently) comparative genomics, and through direct observations of evolutionary change in both natural and experimental populations. Each of thousands of peer-reviewed articles published every year in scientific journals provides further confirmation (though, as Futuyma...notes, “no biologist today would think of publishing a paper on ‘new evidence for evolution’ ... it simply hasn’t been an issue in scientific circles for more than a century”). Conversely, no reliable observation has ever been found to contradict the general notion of common descent. It should come as no surprise, then, that the scientific community at large has accepted evolutionary descent as a historical reality since Darwin’s time and considers it among the most reliably established and fundamentally important facts in all of science. [4]

The evidence for common descent is so strong that even some of the more intellectually honest members of the intelligent design creationist community accept this fact. As biochemist Michael Behe concedes:

When two lineages share what appears to be an arbitrary genetic accident, the case for common descent becomes compelling, just as the case for plagiarism becomes overpowering when one writer makes the same unusual misspellings of another, within a copy of the same words. That sort of evidence is seen in the genomes of humans and chimpanzees. For examples, both humans and chimps have a broken copy of a gene that in other mammals helps make vitamin C As a result, neither humans nor chimps can make their own vitamin C. Of an ancestor of the two species originally sustained the mutation and then passed to both descendant species, that would neatly explain the situation...The same mistakes in the same gene in the same positions of both human and chimp DNA. If a common ancestor first sustained the mutational mistakes band subsequently gave rise to these two modern species, that would very readily account for both why both species have them how. It's hard to imagine how there could be stronger evidence for common ancestry of chimps and humans. [5]

As Gregory notes, the evidence for common descent comes from many disciplines such as biogeography, comparative genomics, and palaeontology, is accepted by the overwhelming majority of life scientists, and has been regarded as a settled fact for well over a century. Given this, it is  hardly unreasonable to have expected the authors commissioned by The Christadelphian to justify the claim that evolution is false to recognise the magnitude of the task they have been assigned and:

• Provide a reliable, factual, accessible assessment of the evidence from comparative anatomy, palaeontology, comparative genomics, biogeography, cell and molecular biology, and developmental biology
• Show that this evidence is better explained by special creationism
• Show why their assessment of the evidence should be believed over that of > 99% of professional biologists who actually work in these disciplines

The previous two articles by a retired science educator and a retired industrial scientist, both of which failed to properly define evolution, let alone show why special creation is a better explanation for the evidence than common descent show that to date, The Christadelphian is failing miserably to even recognise the magnitude of the task it has set itself in refuting evolution, let alone successfully achieve it.

John Hellawell - Halting between fundamentalism and reality

John Hellawell, the author of the April 2015 article "Halting between two opinions" does have a respectable career in freshwater ecology, with a particular interest in areas such as freshwater toxicology and fish biology. However outside of that area, one fails to see any evidence that he has published any robust critiques of evolutionary biology that have been accepted as compelling by his colleagues. What most laypeople fail to realise, as I have said more than once, is that outside a scientist's sphere of competence, his opinion is no more authoritative than any other educated layperson. What this means is that Hellawell is not in a position to offer an authoritative refutation of the evidence for common descent from disciplines such as developmental biology, palaeontology, comparative genomics, and molecular biology which lie outside his area of professional expertise, any more than an orthopaedic surgeon is in a position to dismiss the evidence for general relativity, or an inorganic chemist the evidence for continental drift.

Hellawell's inability to provide an authoritative, informed refutation of evolution is a matter of public record, as one can see from a British Centre for Science Education review of one of Hellawell's anti-evolution public lectures:

When dealing with [the evidence for evolution in the fossil record] he was in his element and told us how Darwin had referred to the fact we should see transitions in the fossil record and lamented the fact we didn’t. 

Here is the quote he gave;

“But, as by this theory innumerable transitional forms must have existed, why do we not find them embedded in countless numbers in the crust of the earth?”

And here is the rest of it, that was kept from the audience by Dr Hellawell;

“It will be more convenient to discuss this question in the chapter on the Imperfection of the Geological Record; and I will here only state that I believe the answer mainly lies in the record being incomparably less perfect than is generally supposed. The crust of the earth is a vast museum; but the natural collections have been imperfectly made, and only at long intervals of time.”

Here is an extract from the chapter Darwin refers to;

“These causes [the imperfection of the fossil record, the limited exploration of the record, poor fossilization of certain body types, etc.], taken conjointly, will to a large extent explain why -- though we do find many links -- we do not find interminable varieties, connecting together all extinct and existing forms by the finest graduated steps. It should also be constantly borne in mind that any linking variety between two forms, which might be found, would be ranked, unless the whole chain could be perfectly restored, as a new and distinct species; for it is not pretended that we have any sure criterion by which species and varieties can be discriminated.”

I think that by anyone’s standards, simply quoting the first line is extremely dishonest and misleading. 

But Hellawell simply went on to claim that the situation had not changed since Darwin’s day. 

He repeated again and again that there were no transition fossils (untrue - and this I could and did challenge in the Q & A)

Hellawell is simply wrong when he asserts that there are no transitional fossils. [6-7] As palaeontologist Steven Gould noted:

Since we proposed punctuated equilibria to explain trends, it is infuriating to be quoted again and again by creationists—whether through design or stupidity, I do not know—as admitting that the fossil record includes no transitional forms. Transitional forms are generally lacking at the species level, but they are abundant between larger groups. [8] (Emphasis mine)

In 1960, T. George Neville pointed out that:

"[t]here is no need to apologize any longer for the poverty of the fossil record. In some ways it has become almost unmanageably rich, and discovery is out-pacing integration: the growing number of species of Formaminifera that remain undescribed in the cabinets of the oil companies probably is of the order of thousands; and while most other organic groups are not so fully collected the ratio of added finds to palaeontologists studying them is constantly expanding. But what remains to be discovered is likely to be of less and less radical importance in revealing major novelties, more and more of detailed infilling of fossil series whose outlines are known. The main phyla, in so far as they are represented by fossils, now have a long and full history that is made three-dimensional by a repeatedly cladal phylogeny. The gaps are being closed not only by major annectant forms, the "missing links" that Darwin so deplored, like the fish-amphibian ichthyostegids, the amphibian-reptile seymouriamorphs, and the reptile-mammal ictidosaurs, but also by new discoveries of phyletic affiliations, as in graptolite structure...Together, the discovery of new fossil forms, the filling out of the details of bioserial change, the interpretation of biofacies, the adoption of new techniques both in fossil morphology and in fossil manipulation, and the establishment of a progressively refined timescale contribute to a present-day palaeontology offering the strongest support, the demonstrative "proof," of the fact and the process of evolution in terms wholly concordant with the essence of Darwinian theory.." [9] (Emphasis mine)

I cannot emphasise enough the point that if you claim that there are no transitional fossils, you are effectively claiming to have surveyed the entire field and found the claims for transitional forms wanting. Given that the fossil record as George pointed out fifty-five years ago is "almost unmanageably rich", that is an extraordinary claim to make. Certainly, it is hard to reconcile Hellawell's assertion with that of George, a geologist and palaeontologist who was in a far better position to provide an assessment of the evidence at the time.

The evolution of the mammalian inner ear from reptilian jaw bones is well established both from embryology (the same bone structures that in reptiles form part of the jaw in mammals form part of the middle ear) and palaeontology. Palaeontologist Kevian Padian, in his trial evidence for Kitzmiller v. Dover points out that fossil evidence for this has been known for decades:

Q. Let's talk about mammals. One of the examples that's referenced in [a creationist textbook]  is the mammalian ear, inner ear. Could you talk to us about how [the creationist textbook] discusses the mammalian ear and what science shows about that? And you've prepared a demonstrative for this?

A. I put a couple of slides together about the transition in the evolution of the mammal ear, which is unusual compared to all the other vertebrates. The next slide I think shows a bit about this. This is going to get a little complex anatomically, but I hope it will only hurt for a minute. The bones of the middle ear, mammals have three of them. You might have heard of them as the hammer, the anvil, and the stirrup.

The stirrup is a bone that's always in the ear, but the mammals have this anvil and hammer thing which are just outside that stirrup bone. These anvil and hammer bones actually correspond to bones that previously made up the upper and lower jaw joint in all the other animals, not just reptiles or anything like them, but everybody pretty much. So the [creationist textbook] authors claim that to make this correspondence is really stretching it, because they said there's no fossil record of this amazing process.

Consider, that to make this change one of these bones had to cross the hinge from the lower jaw into the middle ear region of the skull. Again this is from [creationist textbook] page 121. So they're saying there's no record of this process and it would be an amazing thing to have to change. The next slide shows that there are actually many sources going back several decades that differ, and there are just a few of them there.

The first one was actually an article by Romer, who was the dean of American vertebrate paleontology for half the century, about a cynodont that has an incipient mammalian jaw articulation, and I'll show you what that is in a minute. That comes from the journal Science in 1969. Here's a somewhat later paper by Edgar Allen of Madison, and now it's Chicago, on the evolution of the mammalian middle ear, and then a third one I put there is very recent piece, a little piece in Science by Thomas Marin from Germany and Zhe-Xi Luo, who's curator at the Carnegie museum here in Pittsburgh just a few hours away, one of the great museums in the country, and they are talking about the evolution of these bones in the middle ear something that is uncontroversial as a principle in comparative anatomy of vertebrates in palaeontology.

Q. Now, I note that first article I believe was from 1969.

A. Was.

Q. So this isn't a new development?

A. Oh, no. Oh, no. It's been known for decades. [10] (Emphasis mine)

Evolution of mammalian jaw joint
Source

The 1969 paper by Romer to which Padian refers states in the abstract:

A diagnostic mammalian character is jaw articulation between squamosal and dentary bones, replacing the quadrate-articular joint of reptiles. A newly discovered Argentinian Middle Triassic form shows, for the first time in an ancestral reptile, definite evidence of a squamosal-dentary articulation supplementary to the persistent primitive connection.  (Emphasis mine) [11]

In other words, Romer describes a reptile with both reptilian and mammalian jaw articulation. What we have is a transitional fossil, and one that has been known for over 40 years.

Since then, the fossil evidence for evolution has exploded. The evolution from lobe finned fish to tetrapod is very well documented, with fossils such as Tiktaalik roseae, a Devonian fish, having a wrist, and other tetrapod features. [12-15] The evolution of whales [16], terrestrial hoofed mammals [17], humans [18], birds (from dinosaurs) [19] and mammals from reptile like tetrapods [20] are all well documented. If Hellawell had properly resarched his subject, he would have been aware that as long ago as the 1960s, the assertion that 'no transitional fossils existed' was false, and today, it is simply impossible to declare that there are no transitional fossils, and be taken seriously anymore.

Hellawell's article in The Christadelphian fails to engage with the evidence for evolution

Given Hellawell's demonstrated failure to properly engage with the evidence for evolution as seen in the lecture which the BSCE attended and criticised, one would like to think that he would have learned from this. His article however shows no attempt to do this, spending an inordinate amount of time making a tedious argument pushing the tired 'scientist as god' trope:

Given these almost miraculous gifts of science and technology and the singular failure of the established churches to provide clear teaching and leadership, one can understand why most people accept the claims of science without question. After all, scientists have delivered the miracles, so should they not be held to be virtually infallible? [21]

Actually, most people don't hold scientists as 'virtually infallible', which not only is a straw-man representation of the public perception of science, but a view for which Hellawell provides absolutely no supporting evidence. In fact, one could more plausibly argue for a rise in anti-intellectualism as seen by the growth in anti-vaccine activism, climate change denialism, and the hysteria over genetically modified organisms. [22] In reality, the public perception towards science while generally positive, is hardly one of unquestioning obedience, contrary to what Hellawell alleges. Earlier this year Pew Research Center commented on how scientists and the general public view science and society:

79% of adults say that science has made life easier for most people and a majority is positive about science’s impact on the quality of health care, food and the environment

54% of adults consider U.S. scientific achievements to be either the best in the world (15%) or above average (39%) compared with other industrial countries

92% of AAAS scientists say scientific achievements in the U.S. are the best in the world (45%) or above average (47%)

About seven-in-ten adults say that government investments in engineering and technology (72%) and in basic scientific research (71%) usually pay off in the long run. Some 61% say that government investment is essential for scientific progress, while 34% say private investment is enough to ensure scientific progress is made. [23]

A 2013 Pew Research report found the military at the top of the list of 10 occupational groups seen as contributing “a lot” to society (78%), followed by teachers (72%), medical doctors (66%), scientists (65%) and engineers (63%). The order of ratings for each of the 10 groups was roughly the same in 2013 as in 2009, though there were modest declines in public appreciation for several occupations. 

Public appreciation of scientists’ contribution dropped 5 points from 70% in 2009 to 65% in 2013 with a corresponding uptick to 8% in those saying scientists contribute “not very much” or “nothing at all” compared with 5% in 2009. Views of medical doctors’ contribution fell 3 points from 69% in 2009 to 66% in 2013. Those of engineers stayed about the same (64% in 2009 and 63% in 2013). [24]

What we see here hardly provides evidence to support Hellawell's claim that the public blindly worships science, and neatly subverts his attempt to portray modern science as an idol at whose feet the general public blindly worships, in order to set up his refutation and provide some justification for the false 'science versus religion' dichotomy with which he ends his article. When Hellwell peddles the tired, dated trope of science being the new religion, it is not a good sign that the rest of his article will be an incisive critique of evolution.

This can be seen with his attempt to peddle another tired trope of mainstream Christianity capitulating to evolutionary biology out of a fear of repeating past errors:

The fact that the established churches do not even question evolutionary theory is probably a consequence of past failures. [25]

In fact, the truth of evolution was fairly quickly appreciated by many Christians. As historian of science David Livingstone has pointed out, many of Darwin’s most ardent supporters were theologically conservative Christians:

Darwin’s cause in America was championed by the thoroughgoing Congregationalist evangelical Asa Gray, who set himself the task of making sure that Darwin would have “fair play” in the New World. Let us be clear right away that this cannot be dismissed as capitulation to the social pressure of academic peers. To the contrary, Gray had to take on one of the most influential naturalists in America at the time to maintain his viewpoint – none other than Louis Agassiz, a Harvard colleague who vitriolically scorned Darwin’s theory. But Gray was not alone. Many of his countrymen, associates in science and brothers in religion took the same stand. And indeed even those who ultimately remained unimpressed with if not hostile to Darwin were quite prepared to admit that evolution had occurred. It is surely not without significance that Christian botanists, geologists, and biologists – that is to say, those best placed to see with clarity the substance of what Darwin had proposed – believed the evidence supported an evolutionary natural history. [26] (Emphasis mine)

The reason why mainstream churches don't question evolution is the same reason that they don't question heliocentrism or any other well-established fact.

Hellawell's implication that science and technology are seen as a 'new religion' by an unquestioning public owed everything to bald assertion, an approach which he employs with his first overt attack on evolutionary biology:

In reality, non-scientists can easily be ‘blinded with science’. Even some scientists seem to have difficulty in distinguishing between fact and theory, and this is particularly the case with evolutionary theory. [27]

No evidence is provided to justify his claim that people exhibit a blind spot in differentiating between fact and theory particularly when it comes to evolutionary theory. Once again, it is merely asserted. Ironically, it is Hellawell who appears to show considerable difficulty in differentiating between evolution as fact, and evolution as theory, and this strongly suggests that Hellawell's grasp of scientific epistemology is somewhat superficial. This is suggested by his somewhat slighting reference to theory, as seen by his juxtaposition of the word with fact in the second sentence, could readily be interpreted by the readers of his article, the overwhelming majority of whom will be scientific laypeople, as providing support for the common belief that a scientific theory is just a hunch, guess, or speculation. Given that many people can indeed be 'bounded with science', Hellawell's failure to disabuse people of this common mistake does lend weight to the likelihood that he has difficulty differentiating between theory and fact when it comes to evolution.

What do we mean by fact and theory in science? In science, a theory refers to a well-established collection of facts, tested hypotheses, and observations that has predictive and explanatory power, which is considerably different from what laypeople mean by theory. As Ryan Gregory notes:

The common and scientific definitions of “theory,” unlike of “fact,” are drastically different. In daily conversation, “theory” often implicitly indicates a lack of supporting data. Indeed, introducing a statement with “My theory is...” is usually akin to saying “I guess that...”, “I would speculate that...”, or “I believe but have not attempted to demonstrate that...”. By contrast, a theory in science, again following the definition given by the NAS, is “a well-substantiated explanation of some aspect of the natural world that can incorporate facts, laws, inferences, and tested hypotheses.” Science not only generates facts but seeks to explain them, and the interlocking and well-supported explanations for those facts are known as theories. Theories allow aspects of the natural world not only to be described, but to be understood. Far from being unsubstantiated speculations, theories are the ultimate goal of science. [28]

As for the scientific definition of fact, given that everything in science is regarded as being held provisionally, subject to revision or refutation, it is wrong to think that 'fact' in science is immune to this. However, this does not mean that from a pragmatic perspective there is no certainty in science. As Ryan notes:

Following the definition provided by the US National Academy of Science (NAS) (1998), one of the most prestigious scientific societies in the world, a scientific fact is “an observation that has been repeatedly confirmed, and for all practical purposes, is accepted as ‘true’.” Or, as Stephen Jay Gould (1981) put it in his inimitable style, “In science, ‘fact’ can only mean ‘confirmed to such a degree that it would be perverse to withhold provisional assent’.” It is this insistence on repeated confirmation by data—either through direct observation or reliable inference—that makes a claim to “fact” so much stronger in science. [29]

The difference between fact and theory in science can be readily illustrated by using gravity as an example. Gravity as fact refers to phenomena such as gravitational attraction, planetary motion, gravitational lensing, the mediation of gravity by space-time curvature, and gravitational redshift. Gravity as theory refers to the theoretical explanation proposed to explain these phenomena, with Newton's theory of gravity ably explained the first two phenomena, while general relativity, the currently accepted theory of gravity not only explained the phenomena that Newton's theory did, but also the latter three. General relativity, like Newton's theory of gravity, is not the last word in gravitational theory, if only because it fails to explain gravity at the quantum level. However, and this point needs to be stressed, the fact GR has significant problems does not mean that it it a 'theory in crisis'. GR is a remarkably successful theory which has passed many tests and has considerable predictive and explanatory power. Furthermore, if and when it is is supplanted by a quantum theory of gravity, the phenomena that GR explained do not vanish just because it has been falsified as a theory.

If we move to evolution, then evolution as fact refers to the fact of common descent and large-scale morphological change in the fossil record through time. These are emphatically demonstrated [30] by the biogeographic distribution of species, the fossil record, comparative genomics, atavisms, and comparative anatomy. Evolution as theory refers to the proposed theoretical mechanism to explain the facts of evolution. This point was emphasised by Darwin at least twice. Less than five years after he published the first edition of The Origin of Species, Darwin noted:

Whether the naturalist believes in the views given by Lamarck, or Geoffroy St.-Hilaire, by the author of the ‘Vestiges,’ by Mr. Wallace and myself, or in any other such view, signifies extremely little in comparison with the admission that species have descended from other species and have not been created immutable; for he who admits this as a great truth has a wide field opened to him for further inquiry. [31]

Darwin was clearly emphasising the difference between the fact of evolution, and the question of how it occurred. His proposed mechanism - natural selection - did not meet with universal acclaim, a point that in 1871 he acknowledged, while nonetheless reminding people of the difference between evolution as fact and evolution as theory:

Some of those who admit the principle of evolution, but reject natural selection, seem to forget, when criticising my book, that I had the above two objects in view; hence if I have erred in giving to natural selection great power, which I am very far from admitting, or in having exaggerated its power, which is in itself probable, I have at least, as I hope, done good service in aiding to overthrow the dogma of separate creations.  [32]

Due in no small part to the lack of a robust theory of heredity, natural selection fell out of favour in the scientific world by the late 19th century, with alternative theories of evolution during this 'eclipse of Darwin' such as neo-Lamarckianism, orthogenesis, and mutationism being advanced to explain the fact of evolution. As part of the modern synthetic theory of evolution, natural selection returned to favour in the mid-20th century. 

This is not to say that the modern synthetic theory of evolution is the final word in evolutionary theory, or is free from problems. However, as cell biologist Kenneth Miller notes, the theory of evolution "has proven to be a remarkably flexible scientific framework, brilliantly accommodating new data and even new fields of science, like molecular genetics." [33] It is no more a 'theory in crisis' than general relativity. And, just as gravitational lensing, planetary motion, and gravitational redshift would not vanish if GR was falsified, the facts of common descent and large-scale evolutionary change are not going to vanish if the modern synthetic theory is ever falsified. This is what we mean by evolution as fact and evolution as theory.

The scientific method - yes, it does support evolution

Hellawell correctly notes how the scientific method is not based around proving things, but rather by holding theories provisionally pending further evidence that will either further confirm them, or highlight problems requiring revision or even rejection:

Outside scientific circles it is rarely appreciated that science advances by disproving rather than proving things. An explanation of a scientific phenomenon is only acceptable if it fits the existing data, but if further contrary evidence is obtained it may have to be relinquished and an alternative postulated that fits the new evidence.

Hellawell however neglects to inform his readers that the the facts which the modern evolutionary synthesis seeks to explain - common descent and large-scale change in the fossil record - remain even if the modern synthetic theory of evolution is falsified tomorrow. Certainly, as cell biologist Ken Miller points out,  modern evolutionary theory has demonstrated all the hallmarks of a brilliant theory in its ability to accommodate new data, even those in areas which did not even exist when the theory originally appeared in the mid-20th century. Likewise, evolutionary biologist Ryan Gregory's remark that mainstream science regards the fact of evolution as one of the best-attested facts in science is something about which Hellawell remains silent. Neglecting to inform his readers of the strength of the case for evolution reflects either a deliberate move for rhetorical purposes, or a simple failure to appreciate how strong the case is. Neither option reflects well on the reliability of his argument.

It is not hard to find evidence in the scientific literature of how modern evolutionary theory. The fact of common descent allows one to make a prediction: mammals that either have no teeth, or possess teeth with no enamel should have pseudogenes for tooth enamel protein, given that they descended from ancestors whose teeth had enamel. In a 2009 paper, Meredith et al tested this hypothesis, and found that the evidence confirmed it:

Enamel is the hardest substance in the vertebrate body. One of the key proteins involved in enamel formation is enamelin. Most placental mammals have teeth that are capped with enamel, but there are also lineages without teeth (anteaters, pangolins, baleen whales) or with enamelless teeth (armadillos, sloths, aardvarks, pygmy and dwarf sperm whales). All toothless and enamelless mammals are descended from ancestral forms that possessed teeth with enamel. Given this ancestry, we predicted that mammalian species without teeth or with teeth that lack enamel would have copies of the gene that codes for the enamelin protein, but that the enamelin gene in these species would contain mutations that render it a nonfunctional pseudogene. To test this hypothesis, we sequenced most of the protein-coding region of the enamelin gene in all groups of placental mammals that lack teeth or have enamelless teeth. In every case, we discovered mutations in the enamelin gene that disrupt the proper reading frame that codes for the enamelin protein. Our results link evolutionary change at the molecular level to morphological change in the fossil record and also provide evidence for the enormous predictive power of Charles Darwin’s theory of descent with modification. [34] Emphasis mine

Having pointed out that the scientific method advances by disproof, Hellawell wastes a considerable amount of time on irrelevant digressions such as the disproof of the existence of phlogiston (true but irrelevant), and the 'disproof' of vestigial organs in the human body, and junk DNA (misleading to the point of being false [35], and flat-out wrong, respectively [36]). Going further, he cites Bernard Lovell's aphorism:

When I was a young scientist we knew everything about the universe but now we know practically nothing.

which again is true, but not only ignores the fact that what we have discovered (which is not going to magically vanish) nonetheless rules out many things (geocentrism, young Earth, special creation), but highlights another clumsy rhetorical strategy, which is essentially:

• Look how much we do not know
• Therfore, special creation is true

Needless to say, this is a fallacious line of reasoning, as can be seen if a geocentrist used Lovell's words as proof that "we know practically nothing about the universe", therefore heliocentrism is false.

Creation or Evolution - Hellawell confuses a theology of creation with a science of creation

Another classic special creationist error that Hellawell makes is to confuse a theology of creation with a science of creation, in which references to God as creator are taken as proof of special creation, even though the passages are completely silent about the precise mechanism employed by God. This argument betrays profound ignorance of the concept of Divine agency in which God readily employs secondary causes to effect his will. Robert Roberts - who opposed evolution - nonetheless grasped this essential point:

A first idea to be mastered in apprehending the ways of providence is the relation of the universe to God. All things are in Him, and He, though personally located in the highest heaven, is everywhere present by the Spirit, which is His substance in diffusion, so to speak. Nevertheless, God is different from His works. Creation, as organised by Him and in Him has a fixed nature, in virtue of which it has, by His appointment, an independent action, so to speak. Results ensue from certain conditions without His volition participating in the results. For example: you place a strip of paper in the candle flame: ignition follows. The ignition did not require the will of Almighty God to produce it. It resulted from conditions originally established by His will, but now having permitted independence of action. The same thing is illustrated in the million occurrences of everyday experience. It is essential to recognise it. It constitutes the platform of evidence. There could be no such conception as providence if every thing were due to direct Divine volition. [4]

That God is the creator of the universe no Christian doubts. The question here is the mechanism God employed, and Hellawell errs by assuming that chaining a series of texts that refer to God as creator somehow has something to say about the science of creation. They do not.

There is no excuse for being ignorant of Divine agency as examples abound in the Bible. For example, in Ex 7:4-5, God states:

When Pharaoh does not listen to you, then I will lay My hand on Egypt and bring out My hosts, My people the sons of Israel, from the land of Egypt by great judgments. The Egyptians shall know that I am the LORD, when I stretch out My hand on Egypt and bring out the sons of Israel from their midst.

In fact, God explicitly states in verses 17-18 that he would strike the water with the staff in his hand in order to turn it to blood:

Thus says the LORD, “By this you shall know that I am the LORD: behold, I will strike the water that is in the Nile with the staff that is in my hand, and it will be turned to blood. The fish that are in the Nile will die, and the Nile will become foul, and the Egyptians will find difficulty in drinking water from the Nile.

God however did not literally strike the Nile, but employed secondary methods (Aaron) to achieve his aims. Likewise, God did not literally stretch out his hand to smite Egypt, but rather employed secondary methods - the plagues - to achieve these ends. 

In fact, by the logic that special creationists such as Hellawell employ when they appeal to passages that refer to God as creator in order to disprove evolution, one could just as readily accuse those who accept what developmental biology tells us about foetal development as either teaching 'theistic embryology', or denying the power of God by seeking to find a naturalistic explanation for embryogenesis. Verses such as:

Jer 1:5 Before I formed you in the womb I knew you, and before you were born I consecrated you; I have appointed you a prophet to the nations. 

Psa 139:13 For You formed my inward parts; You wove me in my mother's womb. 

Job 10:10-11 Did You not pour me out like milk and curdle me like cheese; clothe me with skin and flesh, and knit me together with bones and sinews? 

Job 31:15 Did not He who made me in the womb make him, and the same one fashion us in the womb? 

Isa 44:2 Thus says the Lord who made you and formed you from the womb, who will help you 

Isa 44:24 Thus says the Lord, your Redeemer, and the one who formed you from the womb,  “I, the Lord, am the maker of all things,  stretching out the heavens by myself and spreading out the earth all alone."

are fairly emphatic in directly ascribing to God the formation of infants in the womb. In fact, the last verse not only refers to God as forming people from the womb also refers to God as creator. Appealing to that verse as evidence against evolution would also just as validly be used to argue against any attempt to promote a belief in 'theistic embryogenesis' as well as 'theistic evolution.' Developmental biologist and Christian Steve Matheson makes this point eloquently:

Those who simultaneously express Christian belief and affirm evolutionary theory are said to espouse a position called "theistic evolution." The view holds the peculiar distinction of being reviled by both hard-line creationists (who call it "appeasement") and prominent atheist commentators (who deride it as fallacious). I argue that these critics typically fail to articulate objections that are specific to the view. Most creationist critics of theistic evolution object to one or both of these characteristics of the view: 1) its reliance on naturalistic explanation, a feature common to all scientific theorizing; or 2) its embrace of "random" causal events, a feature common to myriad scientific explanations. Most atheist critics of theistic evolution object to its openness to supernatural explanation, a feature of religious belief in general. Such criticisms, valid or not, fail to address anything specific to theistic evolution. In other words, attacks on theistic evolution are usually attacks on theism or attacks on evolution, but rarely represent specific criticisms of the theistic evolution position. To better understand the controversy surrounding theistic evolution, I propose that critiques of the position be considered in light of a lesser-known position we may (with tongue in cheek) call "theistic embryology." Theistic embryology describes the thinking of those who simultaneously express Christian belief and affirm basic theories in human developmental biology. Although the logic is indistinguishable from that of theistic evolution, the view is uncontroversial and the term "theistic embryology" is practically non-existent. I suggest that critiques of theistic evolution be subjected to the "theistic embryology test." Most critiques that claim to identify weaknesses in theistic evolution make arguments that are equally damaging to "theistic embryology" and so fail the test. Critiques that fail this whimsical test are likely to be arguments against belief, or against naturalistic explanation, and should be considered as such. [38]

When Hellawell finally manages to address the actual science (on the fourth page of a five page article!) his arguments are unconvincing at best, and betray a superficial, dated grasp of the subject:

The conventional view of evolution is that it is a random process in which mutations, that is spontaneous changes in the genes, may confer advantages on the organism. These would thus  enable it to be better adapted to its environment and enhance the likelihood of its survival. This is often described as “the survival of the fittest”. When these genetic benefits accumulate and are passed to subsequent generations the species evolves and over time will become another species.  When the process continues over millions of years totally new creatures evolve.  

Two weaknesses are associated with this idea. There is an assumption that those organisms that survive must, by definition, be fitter than the rest. As the late Professor H. Graham Cannon, F.R.S. noted, if we ask which are the fittest the answer must be “those that survive”. This means that Darwin’s theory is “the survival of those that survive” which he did not think was a very profound concept. The other weakness is the very low rate of favourable mutations. Most, if not all, observed mutations do not appear to convey any benefit but just the opposite. About the only example of an advantageous mutation is that which causes sickle-cell anaemia, which confers resistance to malaria, but sufferers from this disease would probably consider that malaria is the lesser problem because there are preventatives and treatments for this, but there are none for sickle cell anaemia. [39]

The fatal flaw with Hellawell's argument - ironic given his claim earlier that some scientists "seem tho have difficulty in distinguishing between fact and theory" is that he fails to differentiate between evolution as fact - common descent - and evolution as theory, and therefore assumes that difficulties real or imagined (very much the latter in this case) with modern evolutionary theory will make the overwhelming evidence for common descent vanish. They do not. The fact of common descent means that Hellawell's attacks on a parody of evolutionary theory are frankly irrelevant to the debate.

Hellawell's first claim is the tired special creationist trope that 'survival of the fittest' is a tautology:

"There is an assumption that those organisms that survive must, by definition, be fitter than the rest. As the late Professor H. Graham Cannon, F.R.S. noted, if we ask which are the fittest the answer must be “those that survive”. This means that Darwin’s theory is “the survival of those that survive” which he did not think was a very profound concept."

This is false, and would appear to betrays Hellawell's a lack of familiarity of the fundamentals of modern evolutionary biology. Robert Keith Elias and John Harshman point out that:

Specific heritable characteristics may include:

• visual sensitivity to yellow
• densest fur
• longest tail feathers

There is simply nothing tautological (in the circular sense) about survival of long tail feathers. That "fitness" is intended to refer to specific characteristics is the core to understanding that SoF is not in any sense a tautology, because by observation we can, for example, establish that those arctic foxes with the densest fur survive to pass on that characteristic. Similarly in a changing environment we may note that in dry years it is the finches with the strongest beaks that survive, while in wet years those with the longest beaks are retained. Hence, instances of SoF are clearly responses to changes in the real world, and repeated failures to see the obvious reactions, would disprove SoF. [40]

Given that special creationists tend to claim that they accept 'microevolution' but not 'macroevolution', it is somewhat incoherent for them to claim that they accept the former, but then claim that 'survival of the fittest' is a tautology. As Harshman and Elias note, "[c]ould it be they don't understand their own argument?"

Hellawell's superficial description of evolutionary biology quoted earlier fails to recognise that not all evolution is adaptive. Genetic drift is another mechanism of evolutionary change, one which due to its random nature is not adaptive:

A commonly held but incorrect stance is that essentially all of evolution is a simple consequence of natural selection. Leaving no room for doubt on the process, this narrow view leaves the impression that the only unknowns in evolutionary biology are the identities of the selective agents operating on specific traits. However, population-genetic models make clear that the power of natural selection to promote beneficial mutations and to remove deleterious mutations is strongly influenced by other factors. Most notable among these factors is random genetic drift, which imposes noise in the evolutionary process owing to the finite numbers of individuals and chromosome architecture. [41]

By failing to recognise that evolutionary change is not exclusively adaptive, the special creationist argument to which Hellawell appeals makes the mistake of thinking that fitness and survival are equivalent. They are not. Harshman and Elias point out that:

Another problem with [the creationist] argument is that it sets up full equivalence between survival and fitness. "Who are the "fittest"? The ones who survive! Why look – it happens every time!"(emphasis added). If that were true, then all differential survival would necessarily be selection. But we have a name for differential survival that isn't selection; it is called drift (basically, changes in a population's gene pool due to chance). And in fact we can often perform tests that distinguish selection from drift. We couldn't do that if selection were just "those that survive survive".

Perhaps the most embarrassing part of Hellawell's argument is H. Graham Cannon, the authority to which he appeals. Cannon, a professor of zoology at the University of Manchester died in 1963, over fifty years ago, which means that he was educated in the first quarter of the 20th century and did much of his research before the modern evolutionary synthesis was forged. Hellawell neglects to provide a reference for the Cannon quotation, but a little searching uncovers that it was from Cannon's book "The Evolution of Living Things", published in 1958! When we look at the quotation in context, Cannon shows the same confused thinking on the subject that special creationists exhibit:

He pointed out, as had Malthus and others before him, that there is a struggle for existence among all living things but now he added that in that struggle it will be the fittest that survive. Now what exactly does this mean? There is a competition and in the result of that competition is is found that the fittest have come out top, Yes, but fittest for what? Fittest to survive! So Darwin pointed out that in the struggle for existence it will be those most fitted to survive who do in fact survive - which is a complete truism - a self-evident truth. Or, put it another way - he said that Nature selected for survival only the fittest. But how could this statement be tested experimentally. What are the fittest? Simply those that survive. So that Nature selects for survival those that survive! [42]

As we've already seen, survival and fitness are not synonymous, as not all evolution is adaptive, given the presence of genetic drift. Furthermore, we can readily test this statement experimentally, as noted earlier. Finally, the creationist argument betrays a failure to differentiate between how fitness is measured, and how it is defined. Mathematician Jason Rosenhouse notes:

In applying the theories of population genetics, it is true that the fitness of a gene is measured by its representation in future generations. But this is far different from saying that fitness is defined that way. Fitness refers to a statistical tendency for certain organisms to bear more young than others. There is nothing tautological in that definition. Furthermore, it is a standard result in probability theory that if your sample size is sufficiently large, the measured freqeuncy of the particular gene in the next generation will be a good approximation to its theoretical value...So there's nothing logically suspect either in the theory or the practice of population genetics. [43]

Hellawell's appeal to an obscure, thoroughly dated reference in order to rebut evolutionary theory again demonstrates how little he knows about the subject he elects to criticise, and strongly hints that outside of his narrow area of competence, his understanding of evolution is mired in the era before the modern evolutionary synthesis.

In passing, it is helpful to note that Cannon appears to have been  one of those holdouts who accepted evolution, but had sympathies with neo-Lamarckianism, as one can infer from the blurb on the back cover of his book:

Professor Cannon's studies of modern experimental embryology and his researches into the functional morphology of various animals...have convinced him that the wonderfully precise and efficient mechanisms that one meets within living things cannot possibly have been brought about by any pure chance device. He takes us back again to Lamarck as a starting point, and demonstrates that there must be a directive forced which controls evolution and that force must reside within the organism. 

Historian of science Peter Bowler notes that Cannon accepted evolution, but:

...retained an interest in the increasingly discredited Lamarckian theory. Lamarckism, the inheritance of acquired characteristics, was traditionally a theory which supposed that evolution was governed by habit…Lamarckism came increasingly under attack from the geneticists of the early twentieth century, but some morphologists and palaeontologists refused to accept the findings of the new experimental biology, Cannons’ increased sense of how habit determined structure seems to have made it difficult for him to abandon the belief in a direct relationship between them via the Lamarckian effect. he assumed that the organism was much more plastic under the influence of the environment than most Darwinians would allow. [44]

Once again, given that Hellawell, as an opponent of evolution, has the burden of proof in showing why special creation is a better interpretation of natural history than evolution, one would expect him to provide an argument based on something far more substantive than  an obscure book well over fifty years old by a forgotten, maverick zoologist whose neo-Lamarckian sympathies on the mechanism of evolutionary change have long since been debunked.

Hellawell's second point - that almost all observed mutations are deleterious - likewise is another tired special creationist trope:

Most, if not all, observed mutations do not appear to convey any benefit but just the opposite. About the only example of an advantageous mutation is that which causes sickle-cell anaemia, which confers resistance to malaria, but sufferers from this disease would probably consider that malaria is the lesser problem because there are preventatives and treatments for this, but there are none for sickle cell anaemia.

This response again shows a considerable ignorance of contemporary evolutionary biology. In short:

• Some mutations are deleterious, some are beneficial, while most are neutral. The literature is replete with examples of beneficial mutations.
• Each human is born with between 60-100 mutations – if they were invariably deleterious, we'd pretty quickly be dead.
• Modern evolutionary biology recognises the importance of networks of genes, in which single mutations often have a negligible effect.

Some mutations are harmful, some are beneficial but others are neutral. Hellawell ignores the fact that a mutation that is beneficial in one environment may be positively harmful in another. The literature is replete with examples of beneficial mutations:

• A point mutation in the apolipoprotein A gene results in the creation of a mutant version of apolipoprotein A, apoA-IM. This beneficial mutation has been linked with reduced rates of atherosclerosis in those heterozygous for the apoA-IM mutation. [45] The clinical significance of this mutation has been explored in many studies. [46][47]
• The CCR5 gene codes for a chemokine receptor that, along with the CD4 T cell co-receptor is used by the HIV-1 virus as an entry point. A mutation in the CCR5 gene conveys resistance to HIV infection in people homozygous for the mutation, while HIV-1 infected individuals heterozygous for the mutation have a two to three year delay before they develop AIDS. The particular mutation is a 32 base pair deletion that results in loss of the CCR5 receptor. [48]
• Bacteria have evolved the ability to metabolise nylon breakdown products. This was achieved by a frameshift mutation which created a unique enzyme that gave the bacteria the opportunity to access a never-before utilised food source. [49]
• In 2008, the evolutionary biologist Richard Lenski published a landmark paper on the evolution by a colony of E. coli bacteria of the ability to metabolise citrate under oxic conditions, something that E. coli is not normally able to do. Over the previous twenty years, Lenski had cultured 12 colonies of E. coli, taking samples every 500 generations to provide a “fossil record”. After 31,500 generations, one colony evolved the ability to metabolise citrate in an oxic environment. The two hypotheses to explain this were (1) an extremely rare mutation or (2) a mutation that was contingent on an earlier mutation to evolve the ability to metabolise citrate. Lenski’s analysis favoured the latter, “Our results instead support the hypothesis of historical contingency, in which a genetic background arose that had an increased potential to evolve the Cit_ phenotype.” [50] 
• Evolution of vertebral steroid receptors and the endocrine systems associated with them involved duplication of an ancestral steroid receptor gene, and mutation of the duplicate. [51][52]

Evolution of specific aldosterone-MR signaling by molecular exploitation. (A) Synthesis pathway for corticosteroid hormones. Ligands for the ancestral CR and extant MRs are underlined; cortisol, the ligand for the tetrapod GR, is overlined. The terminal addition of aldosterone is in green. Asterisks, steps catalyzed by the cytochrome P-450 11β-hydroxylase enzyme; only the tetrapod enzyme can catalyze the step marked with a green asterisk. (B) MR's aldosterone sensitivity preceded the emergence of the hormone. The vertebrate ancestor did not synthesize aldosterone (dotted circle), but it did produce other corticosteroids (filled circle); it had a single receptor with affinity for both classes of ligand. A gene duplication (blue) produced separate GR and MR. Two changes in GR's sequence (red) abolished aldosterone activation but maintained cortisol sensitivity [see (C)]. In tetrapods, synthesis of aldosterone emerged due to modification of cytochrome P-450 11β-hydroxylase. mya, million years ago. (C) Mechanistic basis for loss of aldosterone sensitivity in the GRs. Phylogenetically diagnostic amino acid changes that occurred during GR evolution were introduced into AncCR-LBD by mutagenesis. Dose-response is shown for aldosterone (green), DOC (blue), and cortisol (red). The double mutant (bottom right) has a GR-like phenotype. Arrows shows evolutionary paths via a nonfunctional (red) or functional (green) intermediate. (From ref 7)

• Evidence of chromosomal translocation and segmental duplication in Cryptococcus neoformans. [53]
• Genome duplication in yeast as a source of evolutionary novelty. [54]
• Whole genome duplication as a source of genetic variety is not restricted to yeasts. Examination of the genomes of chordates has shown the existence of multiple copies of genes in the same gene family. None of this is remotely controversial; as long ago as 1999, one paper noted:

Duplication of genes and entire genomes are two of the major mechanisms that facilitated the increasing complexity of organisms in the evolution of life. Gene duplications might be responsible for the functional diversification of genes, the creation of gene families and the generally increased genomic, and possibly also phenotypic, complexity. Protostomes, such as Drosophila, and deuterostome ancestors of vertebrates tend to have single copies of genes whereas chordate genomes typically have more genes, often four; the copies belong to the same gene family. [55]

• Proviral elements from ancient retroviral infections have served as the source of genetic novelty. Placental morphogenesis would not be possible without the cooption of an ancient retroviral envelope protein to perform an entirely different task. [56]
• Horizontal gene transfer in bacteria is responsible for more than just the transfer of antibiotic resistance. One example involves the Salmonella PhoP-PhoQ system which senses environmental magnesium ions, allowing the bacterium to tell whether it is inside a host cell. If this is the case, it activates a molecular pathway that permits it to survive inside the cell. The genes that permit Salmonella to do this are not part of its original genome but were obtained by horizontal gene transfer. [57] 
• Evolution of complexity has been simulated and occurs in a Darwinian manner. [58]

Hellawell's claim that mutations are almost always lethal is simply wrong, and ignores the fact that as we have shown, mutations can be beneficial. More importantly, he overlooks the fact that most mutations are neutral. Lenski’s long term evolutionary experiment highlights the fact that neutral mutations can linger in the genome until another mutation arrives which effects a beneficial phenotypic change. The average human being has around 175 mutations, [59] according to one study so clearly, most of these are not life-threatening, and otherwise we wouldn’t be here! Really serious mutations tend to be purged from the gene pools via purifying selection. Crippling mutations such as those causing Huntingdon’s disease, CADASIL or other genetic disorders are noticeable because of their characteristic phenotype. Neutral mutations are invisible from a phenotypic perspective, so the special creationist simply overlooks their existence.

Hellawell's disparaging and poorly-informed reference to the Drosophila experiments:

Experiments with the common fruit fly, in which exposure to radiation and harmful chemicals created a vast range of genetic mutations have not resulted in a single advantageous mutation.

demonstrate specific ignorance of what these experiments are aimed to achieve. [60] The authors of a recent review paper on experimental evolution using a Drosophila model point out:

Experimental evolution with laboratory populations is an alternative tool with which to study adaptation. One of the most attractive applications of experimental evolution is to create a replicated set of populations that have been differentiated relative to replicated control populations, using a well-defined selection protocol, and then compare the allele frequencies at various loci for associations between particular types of phenotypic and genetic differentiation. In short, laboratory evolution allows biologists to use strong inference tests of hypotheses concerning phenotypic and genetic responses to selection. In addition, the recent development of cost-effective genomic tools has allowed broad and systematic assays of the molecular foundations of the effects of experimental evolution. [61] 

Examples of evolution observed in Drosophila abound:

Stress-resistance characters respond to direct and reverse selection. Laboratory selection for increased resistance to starvation and desiccation produces rapid responses within populations of D. melanogaster, and high heritability estimates have been reported for both traits. Direct selection for increased starvation (Rose system “SO” and SB” lines) and desiccation (Rose system “D” lines) resistance results in a correlated increase in longevity in the absence of acute starvation or desiccation, along with decreased fecundity...Furthermore, some experiments suggest that lines selected for increased desiccation resistance have decreased preadult viability and slower development time than control lines. There appear to be complex trade-offs connecting resource acquisition during larval stages, adult stress resistance, and life history generally. [62] 

Pseudocomparative surveys and reverse-selection experiments reveal correlations between stress resistance and life history characters. The mean longevity of Drosophila populations has been demonstrated to change as a result of manipulating the age of reproduction in a population over multiple generations. Furthermore, longer-lived lines (Rose system “O” lines) have generally been found to tolerate starvation and desiccation significantly better than lines with shorter average lifespans (Rose system “B” lines). These pseudocomparative results were interpreted to mean that resistance to starvation and desiccation might be general physiological mechanisms necessary for maintaining health at late ages. [63]

It hardly needs stressing that there is no ‘limit’ to evolutionary change, but a reference to documented speciation in Drosophila should make this clear, and prevent any further creationist attempts to peddle the usual misunderstandings about Drosophila experiments.

Special creationists such as Hellawell have a thorough dated view of evolution which begins and ends with selection working on single point mutations ignores the fact that modern evolutionary biology recognises the importance of networks of genes, and that fixating on single beneficial or deleterious mutations is trivialising evolution. The developmental biologist Paul Myers makes this clear:

Mutations are the root of biological variation, of course, but we often have a naive view of their consequences. Most mutations are neutral. Even advantageous mutations are subject to laws of chance in their propagation, and a positive selection coefficient does not mean there will be an inexorable march to fixation, where every individual has the allele. This is also true of deleterious mutations: chance often dominates, and unless it is a strongly negative allele, like an embryonic lethal mutation, there's also a chance it can spread through the population. 

Stop thinking of mutations as unitary events that either get swiftly culled, because they're deleterious, or get swiftly hauled into prominence by the uplifting crane of natural selection. Mutations are usually negligible changes that get tossed into the stewpot of the gene pool, where they simmer mostly unnoticed and invisible to selection. Look at human faces, for instance: they're all different, and unless you're looking at the extremes of beauty or ugliness, the variations simply don't make much difference. Yet all those different faces really are the result of subtly different combinations of mutant forms of genes.  

"Combinations" is the magic word. A single mutation rarely has a significant effect on a feature, but the combination of multiple mutations may have a detectable or even novel effect that can be seen by natural selection. And that's what's going on all the time: the population is a huge reservoir of genetic variation, and what we do when we reproduce is sort and mix and generate new combinations that are then tested in the environment. [64]

It can be quite difficult to get this simple point across – really serious mutations tend to kill in utero. Even then, some deleterious mutations can be beneficial in some environments, as the persistence of sickle cell anaemia in malaria-endemic areas demonstrates. Hellawell's fatuous comment that "malaria is the lesser problem because there are preventatives and treatments for this, but there are none for sickle cell anaemia" ignores the fact that prior to the introduction of modern medicine, malaria was a greatly feared disease which caused considerable morbidity and mortality. Homozygous individuals (that is, those with two copies of the sickle cell gene) are affected, but those with a single copy have a considerable survival advantage, which is of course why the trait persists in malarial endemic areas.

Thinking in terms of networks of genes helps realise the fallacy behind the “mutations are deleterious therefore evolution can’t occur” fallacy. Below is the signalling network for the epidermal growth factor pathway.

A creationist likely would argue that a just a single mutation would destroy this cellular pathway, but this is actually not the case. Often, the effect of a mutation in one of the genes involved in such complex pathways is negligible. Myers again:  

The curious thing is, though, that the more elaborate the network, the more pieces tangled into the pathway, the smaller the effect of any individual component (in general, of course). What we find over and over again is that many mutations to any one component may have a completely indetectable effect on the output. The system is buffered to produce a reliable yield.

Now do you see what's wrong with the simplistic caricature of evolution at the top of this article? It's superficial; it ignores the richness of real biology; it limits and constrains the potential of evolution unrealistically. The concept of evolution as a change in allele frequencies over time is one small part of the whole of evolutionary processes. You've got to include network theory and gene and environmental interactions to really understand the phenomena. And the cool thing is that all of these perspectives make evolution an even more powerful force.

His attacks on evolution also betray ignorance of the fundamentals of population genetics. He asserts that:

I believe that even if a favourable  mutation occurred, the probability of its being effective and passed on to succeeding generations is very low.

This is simply wrong. As the geneticist and evolutionary developmental biologist Sean Carroll points out, even a favourable mutation that conveys only a slight fitness advantage over other member of the population can rapidly become fixed in the population.

Now let's turn to the question of the spread of the black fur color mutation. Once the mutation exists, its spread is a matter of selection and time. The key factors are the selective advantage of the black fur trait, and the effective population size (this is not the total number of individuals, but takes into account the breeding population and other factors, it is designated N_e). The greater the advantage, the faster it will spread, but the greater the size of the population, the longer it will take before every mouse is black. The formula for the average time (t, in generations) required until most of the mice are black is: 

t = (2/s) natural log (2N_e ) generations 

Here are some values of t as a function of the advantage s for a population size of 10,000 individuals; note that as the selection coefficient increases, the amount of time for the favorable mutation to spread decreases:

s = 0.001	time = 19,807 generations
s = 0.01	time =1981 generations
s = 0.05	time = 396 generations
s = 0.1	time =198 generations
s = 0.2	time = 99 generations

The estimated selection coefficient for dark mice living on black lava flows is greater than 0.01. Consulting the table above reveals that the dark fur mutation would spread completely in fewer than 2000 generations, or less than 2000 years. This shows that even a mutation of slight benefit will spread in a time span that is short in geological terms. [65]

Had Hellawell bothered to check a popular book on evolutionary biology let alone a reference on population genetics, let alone the standard references, he would not have made such an error.

It is not clear what Hellawell's point is in the remainder of his paragraph, but it again shouts considerable unfamiliarity with modern trends in evolutionary biology, particularly evolutionary developmental biology:

 During embryonic development, the fertilised egg divides into two, four, eight cells and so on, eventually producing a large number of cells. At a certain stage, the destiny of some of these cells is determined and they will become the reproductive cells of the adult, while the others form the rest of the body. If a mutation occurs in the reproductive cells it might be passed on to a future generation but it cannot confer benefit on the adult. If it occurs in the somatic cells, that is those that will form the body, it could benefit the adult but it would not be passed on to offspring. This means that the ‘window of opportunity’ to confer evolutionary benefit is limited to mutations that occur in the very early stages of development, usually lasting only a relatively short period.

The discovery that animals share a group of 'tool kit genes' involved in the development of organs and body parts during embryogenesis not only has been one of the major breakthrough in developmental biology in recent years, but has shown us how mutations in that 'relatively short period' can result in developmental repatterning and large-scale evolutionary change. Developmental biologists and geneticist Sean Carroll gives a splendid example of how this happens:

The three-spine stickleback fish occurs in two forms in many lakes in North America—a shallow-water, bottom-dwelling, reduced-spined form and an open-water, full-spines form...The pelvic spines are actually part of the fishes’ pelvic fin skeleton, and the pelvic and pectoral fins are repeated structures. Pelvic spine length is under selection pressure from predators. In the open water, longer spines help protect the fish from being swallowed by larger predators. But, on the lake bottom, long pelvic spines are a liability. Dragonfly larvae seize and feed on young sticklebacks by grabbing them by their spines. 

The evolution of these stickleback populations is very recent. The lakes they inhabit were formed by receding glaciers in the last ice age, approximately 10,000 years ago and each lake was colonized by oceanic sticklebacks that then rapidly and repeatedly diverged into the short-and long-spined populations. Exceptional fossil records of stickleback evolution have been uncovered that document their rapid evolution. 

Because the two populations are so recently evolved, they can still mate together and produce offspring. This allows geneticists to trace the genetic changes that underlie the divergence of body forms. Recently, David Kingsley, Dolph Schluter, and their collaborators at Stanford University and the University of British Columbia have been able to pinpoint genes responsible for the evolution of different traits in sticklebacks. The evolution of one trait, the pelvic spines, reveals how the formation of a repeated structure evolves through changes in the way a tool-kit gene is used. 

The reduction of pelvic spines in bottom-dwelling populations is due to a reduction in the development of the pelvic fin bud. The major gene responsible for the reduction of the pelvic skeleton was recently identified as a tool-kit gene called Pitx1. This is a typical tool-kit gene—it has several jobs in the development of the fish, it acts by controlling other genes, and has counterparts in other animals, such as the mouse. In the mouse, Pitx1 helps make the hindlimb different from the forelimb (limbs are another repeated structure). 

We know from the fossil record that the pelvic fin was the evolutionary forerunner of the hindlimb of four-legged animals. The use of Pitx1 in the development of the pelvic fins in fish and in mammal hindlimbs is a very nice, independent piece of evidence supporting that history. But the main point I want to make here is how the fishes’ pelvic skeleton gets reduced by changes at the Pitx1 gene without affecting other body parts where Pitx1 also functions. 

The big clue comes from comparing the Pitx1 proteins of the pelvic-reduced and full pelvic forms. There is not a single difference in the protein sequence. 

But, wait, didn’t I say that changes at Pitx1 made the pelvic skeleton different? Yes, I did. The apparent paradox is resolved by understanding that, in addition to the coding part of a gene, every gene also contains noncoding DNA sequences that are regulatory. Embedded in this regulatory DNA are switchlike devices that determine where and when each gene is or is not used. Tool-kit genes can have many separate switches, with each switch controlling the way a gene is used in a different body part. The function of switches depends on their DNA sequence, and changes in their sequence can alter how they work. A critical property of these switches is that changes in one switch will not affect the function of the other switches. And therein lies a huge insight into how form evolves. That is, the use of a tool-kit gene can be fine-tuned in one structure without affecting any other structures. 

In the pelvic-reduced stickleback, the Pitx1 gene is, in fact, not used in pelvic fin development. Changes in the switch that govern its use in the hindlimb have enabled the selective reduction of this part of the fishes’ skeleton...The power of this example lies in its demonstration of how, at the fundamental level of DNA, a major change in body anatomy can rapidly evolve.” [66]

Two forms of stickleback fish occur in many lakes, the bottom-dwelling form has a reduced pelvic skeleton. The reduction of the skeleton is due to a change in the function of a genetic switch controlling the use of the Pitx1 gene in the developing pelvic fin (X). Drawing by Leanne Olds.

Hellawell's attacks on evolution betray a failure to differentiate between evolution as fact and evolution as theory, as well as a profound ignorance of the subject he criticises. In 2009, the British Centre for Science Education members who attended one of his lectures pointed out the many flaws in his attacks on evolution. Unfortunately, he has learned nothing from this event, and still makes attacks on evolutionary biology that are dated and flatly wrong.

Distorting the teaching of Scripture

While our community has traditionally opposed evolution, it has also rightly prided itself on a rational approach to Bible study. Unfortunately, over the last half-century, the crude fundamentalism that drives large sections of  evangelical Christianity has maintained a death-grip on much of our community, with a flat literalism and a tendency towards dogmatism being painfully evident in much recent exegesis. Hellawell's concluding words positively exude this spirit:

The concept of theistic evolution also contradicts the repeated statement that God created our world and all its inhabitants. Creation was propounded by the Lord Jesus and the Apostle Paul. If the Son of God, the Apostle Paul, the Psalmists and the Prophets were wrong on this matter, then we are in very serious trouble.

Hellawell's fundamental mistake is to confuse his own uninspired, literal reading of the Bible with the inspired message. As we've noted before, he has confused a theology of creation with a science of creation, an approach which shows a regrettable lack of familiarity with the concept of divine agency, where God acts through secondary causes. Worse, Hellawell has needlessly created a conflict between the two books of divine revelation - the Bible and the natural world - by this failure to differentiate between creation as theology, about which the Bible is eloquent, and creation as science, about which it is entirely silent. When Hellawell uses frankly manipulative language such as his assertion that if Jesus, Paul, and the authors of the Bible were wrong on creation, then "we are in very serious trouble", he is deliberately creating a potential crisis of faith by pitting the Bible against science. Those who have been indoctrinated with the belief that evolution denialism is a first principle of the one true faith can hardly be blamed for abandoning faith when they discover that contrary to Hellawell's assertions, evolution is a fact. [67]

Over 150 years ago, W.D. Jarding pointed out that:

The inconsistency spoken of between nature and scripture, arises not from antagonism, but from the misinterpretations of both. It is man’s interpretation of the one set against man’s interpretations of the other. It is not nature versus scripture, but false science against true theology, or false theology against scientific fact. Some scientific men, we believe, view the Scriptures through the distorted medium of “confessions of faith” and doubt them, and theologians view science and call it false, because it does not take to their turn-pike road. [68]

Given that the fact of evolution has not been in doubt for well over a century, with recent discoveries in genetics emphatically confirming this, any contradiction between Bible and science owes everything to faulty exegesis. I have pointed out elsewhere how a proper interpretation of the creation narratives recognises that they were given to a pre-scientific community not to instruct them in science, but to preserve their faith in the presence of rival belief systems. Genesis is a polemic against ancient Near Eastern theology which accommodates a pre-scientifc world view without endorsing it. C.C. Walker put it well:

Moses’ testimony is not so “plain” that it cannot be misinterpreted or misunderstood...Moses’ testimony was given to Israel in what might be called the infancy of the world, when men did not know the extent of the earth, let alone that of the sun, moon, and stars. And, as we believe, it was given (by God through Moses), not so much to instruct Israel in cosmogony in detail, as to impress upon them the idea that The Most High God is the Possessor of Heaven and Earth (Gen. 14:22). And this against the claims of the gods of the nations, as was abundantly proved in Israel’s history. [69]

Hellawell needlessly creates a conflict between Bible and science by his fundamentalist distortion of the Bible in which theological references to creation are anachronistically read as scientific declarations about the mechanism of creation. By recognising that Genesis 1 is ancient cosmology and not modern science, we decouple the creation narratives from any question of how God created, a move which eliminates the needless evolution-creation battle, and allows us to really make sense of Genesis 1. [70]

Hellawell ends by invoking the "halting between two opinions" trope which while a valid exhortation, in this case is yet again attempting to frame the discussion in terms of a false dilemma. The real question we face today is not evolution versus creation, but faith versus unbelief. By making evolution and creation mutually exclusive, instead of recognising the former as a means of achieving the latter, Hellawell and his fellow special creationists are simply helping catalyse a drift from faith to unbelief for those who have bought into this false dilemma.

An honest reading of the natural history of this planet rules out special creation, and if I can rework the 'halting between two opinions' theme, we have been confronted with unarguable evidence that the mechanism of creation employed by God was an evolutionary one. We need to choose between accepting the witness of creation, or privileging a human distortion of Bible and science over that witness. Over a century ago, C.C. Walker contemplated the implications for our faith for the possibility that extinct giant birds were ancestral to modern birds: 

The professors tell us for instance that some of these ancient birds, whose strides we can see for ourselves from their footprints were from four to six feet long, were like gigantic ostriches. Supposing that it were ever established that they were the actual progenitors of our smaller forms (“There were giants in the earth in those days” might apply to to birds and beasts), would the credibility of the Mosaic narrative suffer? Not at all, in our estimation. We should indeed have to revise somewhat our interpretation of the brief cosmogony of Gen. 1.; but should not waver as concerning its divinity, nor await with less faith and patience the reappearance of Moses in the land of the living. [71]

As has been amply confirmed, modern life is related to ancient, extinct forms of life via a process of descent with modification. As Walker notes, that means we do indeed need to revise our interpretation of the creation narratives, but it does not diminish one iota our faith and confidence in its author.

References

1. "It is wrong to hold creation and evolution as mutually exclusive alternatives. I am a creationist and an evolutionist. Evolution is God's, or Nature's, method of Creation. Creation is not an event that happened in 4004 B.C.; it is a process that began some 10 billion years ago and is still under way." Dobzhansky T "Nothing in Biology Makes Sense Except in the Light of Evolution", American Biology Teacher (1973) 35: 125–129

2. Mainstream scientists frequently point out that over 99.9% of mainstream scientists accept that the evidence confirms the reality of evolution. This is not hyperbole. As historian of science Ronald Numbers points out, formal lists of those who ‘dissent from Darwin’ represent a vanishingly small percentage of the total population of scientists: “After more than a decade of effort the Discovery Institute proudly announced in 2007 that it had got some 700 doctoral-level scientists and engineers to sign “A Scientific Dissent from Darwinism.” Though the number may have struck some observers as rather large, it represented less than 0.023 percent of the world’s scientists. On the scientific front of the much ballyhooed “Evolution Wars,” the Darwinists were winning handily. The ideological struggle between (methodological) naturalism and supernaturalism continued largely in the fantasies of the faithful and the hyperbole of the press.” - Ronald Numbers "Creationism, intelligent design, and modern biology" in Biology and Ideology: From Descartes to Dawkins Eds Alexander D.R., and Numbers R.L. (2010: University of Chicago Press) p 327-328

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6. Prothero D.R. Evolution: What the Fossils Say and Why it Matters (2007: Columbia University Press)

7. Hunt K Transitional Vertebrate Fossils FAQ TalkOrigins Archive

8. Stephen Jay Gould, Evolution as Fact and Theory, Hen's Teeth and Horse's Toes: Further Reflections in Natural History, New York: W. W. Norton & Company, 1994, p. 260

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10. The testimony of Kevin Padian in Kitzmiller v. Dover

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21. Hellawell J.M. "Halting between two opinion" The Christadelphian (2015) 152:162-166

22. Gatehouse J "America dumbs down: a rising tide of anti-intellectual thinking" Macleans May 15 2014

23. Funk C, Rainie L "Public and Scientists’ Views on Science and Society" Pew Research Center January 29 2015

24. ibid

25. Hellawell, op cit p 162

26. Livingstone D.N. “Darwin’s Forgotten Defenders” (Eerdmans 1984) p xi-xii

27. Hellawell, op cit p 162

28. Gregory, op cit p 47

29. loc cit

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35. Hellawell makes the classic special creationist mistake of confusing vestigial with functionless. This is wrong. A vestigial structure is one which has lost most or all of its ancestral function. Whether it has secondarily acquired an unrelated function (such as the human coccyx which is a vestigial tailbone, but now serves as an attachment for pelvic floor muscles) is irrelevant to the question of a structure's vestigial status. Certainly, the presence of vestigial inner wings under the fused outer wing covers of flightless beetles, and the skin-covered eye remnants in mole rats are examples of vestigial structures with no function that make perfect sense in the light of evolution, but are impossible to explain honestly from a special creationist point of view.

36. At least two thirds of the human genome is junk DNA which neither codes for protein, nor has any regulatory function. It is unarguable evidence of non-sentient design in the genome, as evolutionary biologist John Avise points out: "[t]hese range from de novo mutational glitches that collectively kill or maim countless individuals (including embryos and fetuses) to pervasive architectural flaws (including pseudogenes, parasitic mobile elements, and needlessly baroque regulatory pathways) that are endogenous in every human genome."

37. Roberts R The Ways of Providence (1881: Birmingham) p 8

38. Matheson S "Theistic embryology: the gathering storm" Quintessence of Dust 2 May 2009

39. Hellawell, op cit p 165

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52. Fraser J.A. et al "Chromosomal Translocation and Segmental Duplication in Cryptococcus neoformans" Eukaryotic Cell (2005) 4:401-406

53. Kellis M, Birren B.W, Lander E.S. “Proof and evolutionary analysis of ancient genome duplication in the yeast Saccharomyces cerevisiae” Nature (2004) 428:617-624

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60. ibid, p R1847

61. ibid, p R1849

62. loc cit.

63. Dobzhansky, T, Pavlovsky, O "An experimentally created incipient species of Drosophila", Nature (1971) 23:289-292.

64. Myers PZ “It’s more than genes, it’s networks and systems.” Pharyngula July 24th 2010.

65. Carrol S.B. The Making of the Fittest: DNA and the Ultimate Forensic Record of Evolution (2006: W. W. Norton & Company) p 61-62

66. ibid, p 205-207

67. This is not a rhetorical flourish. Comments such as "My own eldest son has decided he cannot be baptized because he has seen the evidence for evolution with his own eyes, and our ecclesia will not tolerate discussion on the subject. Unlike some young people, he is too honest to say he doesn’t believe it, just so that he can ‘pass the test’ and be baptised” are hardly uncommon, and are an indictment on the fundamentalists in our community who put blind adherence to human dogma over true belief.

68. Jardine W.D. "The Bible as a Law of Life and Immortality" The Ambassador of the Coming Age (1864) 1:93-94 

69. Walker C.C. "Is it 'Wrong' to Believe that the Earth is a Sphere?" The Christadelphian (1913) 50:348

70. "It seems to me that this kind of reading of Genesis not only makes good sense of the text within its cultural horizons, but puts the emphasis back where it belongs. Perhaps it is time to stop warring, for example, over the length of the days and instead to recall what Genesis 1 is more likely about. This world is God's temple-palace and he has not abandoned it. If we are truly to bear his image, then neither should we. Not only so, but every human being is made in God's image. From this perspective, it makes a great deal of sense for Jesus as God's son among us not only to cleanse Israel;s microcosmic temple, but also to restore our image, opening blind eyes, deaf ears, raising the dead, etc. Little wonder Paul speaks of a new creation. With these truths firmly in mind and heart, it would be difficult for Christians not to change the world." Rikki Watts. Making Sense of Genesis 1.

71. Walker C.C. "Genesis" The Christadelphian (1910) 47:501