Power to the PC police?:Pros and cons.

A clash of Titans XXXII

Truth is dangerous III

Darwinism can't win even with loaded dice.

Researchers Ran a Massive Yearlong Experiment to Get Bacteria to Evolve. Guess What Happened?

Evolution News & Views

It's a struggle out there. You have to be fit to survive. When the pressure is on, nature favors the ones who can take the heat.

It's a theme that has been drummed into our heads since school. It's a cultural meme. Social Darwinists used it to justify atrocities -- see the new documentary The Biology of the Second Reich. Today's kinder, gentler Darwinists downplay the violence in the struggle for existence, yet the fact as they see it is inescapable: environmental circumstances select random genetic mutations that confer fitness, i.e., survival, by allowing organisms to adapt.

That in a nutshell explains the development of complex life forms. We're assured there are gobs of evidence for it, too.

Looking into a recent paper in PNAS about evolutionary fitness tradeoffs, you have to feel sorry for a team of five evolutionists from UC Irvine who did their level best to produce clear evidence for the favored story. They began with a startling revelation:

Despite the centrality of adaptation to evolution, surprisingly little is knownabout the diversity of mutations that contribute to adaptation or about their phenotypic and fitness effects (1). There are, in fact, only a few well-known examples linking genotype, phenotype, and adaptation in nature (2-4). (Emphasis added.)

Those references are worth a glance. Reference (1) is to H. Allen Orr (2005), "The genetic theory of adaptation: a brief history,"where he states, "Here I survey the history of adaptation theory, focusing on the rise and fall of various views over the past century and the reasons for the slow development of a mature theory of adaptation."

References (2-4) surely must represent what, in the authors' opinions, constitute the best "well-known examples linking genotype, phenotype, and adaptation in nature." What are they? #2 is about stickleback fish that gained or lost body armor, but the authors admit, like these ones do, that "the genetic and molecular basis of morphological evolution is poorly understood." #3 is about mice with varying coat colors due to a single mutation that allows light-colored mice to survive better on light backgrounds and dark-colored mice to survive better on dark backgrounds (a kind of "peppered mice" story). #4 is about a gene in butterflies that affects wing pattern mimicry. So these are their best examples linking genes to adaptation. What became of Darwin's finches and peppered moths?

Moving right along, the UC Irvine team next offers an excuse for this lack of evidence:

In nature, this connection is often complicated by factors such as varying selection pressures or underlying genetic heterogeneities. Although the task is difficult, the general inability to connect phenotype to genotype in the context of environmental adaptation has been a major failing in the field of evolution.

So they are here to fix that epic fail. After listing four complicating factors in their study, they say this in the last sentence of the paper:

Given the breadth of these complexities in a well-controlled experimental system, it is no wonder that the mapping of genotype, phenotype, and fitness continues to be a daunting task in natural populations.

In a moment we will see what they did and what went wrong, but first pause to be astonished.This is the theory that is so well-established by mountains of evidence, we are constantly told, that any criticism of it must be stifled as ignorant, and only this theory must be allowed to be considered scientific. They have just told us otherwise. "Surprisingly little is known" about it, and the best examples they could produce are all instances of trivial variations among existing species. If they had better examples, they surely would have brandished them proudly instead of giving excuses about how hard it is to find genetic evidence for adaptation.

The Experimental Test

Their experiment should have been ideal for testing the genetics of adaptation: 2,000 generations of E. coli bacteria subjected to heat. "In total, we performed >800 fitness competitions, making this one of the largest studies of its kind." The games are on! Evolve or perish! Long live the fittest!

Their "large-scale experiment" started with an "ancestral strain" of E. coli bacteria that they replicated 115 times and subjected to high temperatures (42.2 °C, or 108 °F) for 2,000 generations. "At the end of the experiment, fitness was measured at 42.2 °C for a single clone from each of 114 lineages; on average, fitness increased ∼40% during the yearlong experiment" (meaning, there were still some that hadn't died of heat exhaustion).

The hunt was on for genetic mutations that conferred ability to take the heat. "We sequenced the genome of these 114 clones, identifying 1,258 mutations relative to the ancestral genome," they say. To decide which mutations most likely had something to do with fitness, they identified two "adaptive pathways," both affecting RNA polymerase (RNAP). Clones could survive with one or the other mutation, but not the two together: "mutations in the two pathways were strongly negatively associated." (This is called negative epistasis; more on that later).

Their challenge of linking genetic mutations to fitness, though, was only beginning.

Our thermal stress experiment has identified many putatively beneficial mutationsthat lead to higher fitness under thermal stress. However, we still do not know the phenotypic consequences of these mutations or their relationship with fitness. Do the apparently distinct adaptive pathways converge on similar phenotypes? Or might the two pathways ... lead to alternative phenotypic solutions to a common selective pressure?

Here we begin to address these questions by measuring a complex phenotype: the magnitude of fitness tradeoffs across a thermal gradient. Evolutionary tradeoffs, which are defined as reduced fitness in a nonselected environment, are of great interest in their own right; they are widely observed and frequently assumed to govern and constrain trait evolution.

The operative word there is "assumed." For example, all these mutations may have been neutral, with no phenotypic consequences. Or, mutations for better survival in heat might have had negative consequences for surviving cold (an evolutionary trade-off), with no overall gain in fitness. "Whatever the cause, tradeoffs have rarely been linked to specific genetic variants" -- another embarrassing revelation.

Paltry Results

In this ideal setup (one of the largest of its kind, remember), they were not even looking for a glamorous innovation, like a wing or an eye. Just connecting a particular mutation to a functional phenotype would have been rated a great success, even if all it meant was shifting the germ's optimum temperature range by a few degrees. Trade-offs notwithstanding, so what if the fittest germ in the hot tub would shiver in the cold bath? They would at least be able to connect "genotype, phenotype and adaptation" together -- the kind of evidence neo-Darwinians need and want.

They found that half the clones shifted their thermal range upward by a few degrees (losing ability to survive cold -- the trade-off), and others survived the heat without losing ability to survive cold. Then they found two independent mutations in the RNAP gene that appear relevant to those shifts, as long as they don't occur together. Success? Not so fast.

For one thing, they don't know why those mutations had that effect. They suggested that they might slow RNAP down when its tendency under heat stress is to speed up, thus improving its likelihood to finish a protein synthesis, but this was not clear. Also, to their surprise, the ancestral strain could sometimes bounce back from doom through the "Lazarus effect" (resurrection from the dead) -- but they don't know how that effect works.

Surprisingly, however, w_a [absolute fitness] of the ancestor was negative (w_a = −0.290) but not significantly <0 .00="" 45.0="" able="" and="" at="" fig.="" nbsp="" s1="" s2="" strong="" style="border: 0px; margin: 0px; outline: 0px; padding: 0px;">This unexpected behavior

 was caused by the occasional sudden recovery of populations whose densities had initially declined markedly, a phenomenon known as the "Lazarus effect".

So how is Lazarus coming out of the grave? They don't know. Maybe there is some "preadaptation" to heat in these bacteria:

At the upper end of the thermal niche, most (>95%) of the clones persist at 45 °C, signaling an expansion of their niche at least 2 °C beyond that of the ancestor (Fig. 1B). This observation contrasts with a previous study in which only one of six 42 °C-adapted lines expanded their upper thermal limit but suggests a degree of "preadaptation" to temperatures beyond the clones' immediate experience. Above 45 °C the analyses become complicated by the Lazarus effect, in whichdeclining populations suddenly recover, presumably due to major effect mutations. Indeed, the ancestral clone, which is habituated to laboratory conditions of 37 °C, does not persist at 43 °C but often recovers at 45 °C (Fig. S2). We do not yet know the molecular processes underlying the Lazarus effect, but two seem possible: either the fitness effects of mutations change as a function of the intensity of stress or the mutation rate increases under high stress (33, 34). We do not yet know which of these two mechanisms predominates.

Complicating matters even more are things like "negative epistasis" (mutations that counteract each other) and "antagonistic pleiotropy" (unintended consequences of a "beneficial" mutation on other parts of the genome).

In short, it was hard to find anything beyond a "suggestion" or a "scenario" that these bacteria improved their fitness in any way by genetic mutations, other than the gross observation that some of the clones managed to survive at 45 °C. But even the ancestor could do that sometimes through the "Lazarus effect." The authors also ignored the possibility that E. coli have ways to generate their own mutations under stress. That would be supportive of intelligent design, as would the notion that bacteria contain "a degree of preadaptation" to temperatures beyond their immediate experience.

Some experiment. What we learn from this paper is that under ideal conditions, with the best methods, scientists have a devil of a time trying to establish neo-Darwinian theory in a scientifically rigorous way. A look at their references shows a debt to Lenski's methods that similarly produced paltry results on one of the longest-running experiments in history trying to demonstrate evolution in a lab.

Is this a theory that deserves to rule the world?

Microevolution+Microevolution=? II

Nature's Microevolutionary Gems Part 2: Bird-Sized Evolutionary Change
Casey Luskin 

In Nature's evolution-evangelism packet, two of Nature's "evolutionary gems" looked at birds. The first such gem showed "Differential dispersal in wild birds" -- but before we get caught up in the jargon, let's just cut to the main question: What sort of evolutionary change was observed? From reading Nature's evolution-evangelism packet, one is told that the "findings illustrate the large effect of immigration on the evolution of local adaptations and on genetic population structure" or that "evolutionary differentiation can be rapid and occur over surprisingly small scales." So exactly what was this rapid, large evolutionary change?
In one study it turns out that female members of the bird species Parus major (common name: "great tit") bred on the western end of the Dutch island of Vlieland tend to lay 1.15 � 0.14 eggs per clutch more than females bred in populations on the east end of the islands. You read that right. The birds native to the island are still reproductively compatible with "immigrant" birds. The fact that evolutionary biologists consider a difference of 1.15 � 0.14 eggs per clutch to be a "large effect" on a population shows just how desperate they are to find evidence of biological change in nature. (See Erik Postma & Arie J. van Noordwijk, "Gene flow maintains a large genetic difference in clutch size at a small spatial scale," Nature 433:65-68 (January 6, 2005).)

Another study cited in this "gem" promised to show "marked evolutionary differentiation" at "small spatial and temporal scales." Readers learned that over a span of about 35 years, great tits from the eastern part of the Wytham woodland in southern England saw a decrease in adult body size that amounted to a net average change of about 1 gram (less than 10 percent of total body mass). Fledgling birds likewise saw a small change in body mass. (Birds in the northern part of the wood did not experience such a change.) (See Dany Garant, Loeske E.B. Kruuk, Teddy A. Wilkin, Robin H. McCleery & Ben C. Sheldon, "Evolution driven by differential dispersal within a wild bird population," Nature 433:60-65 (January 6, 2005).)

Recall that Nature's introduction to the packet boasts that "all life evolved by natural selection" and claims that this is "a fact, in the same way that the Earth orbits the Sun is a fact." Nature claimed the packet would show "just what is the evidence for evolution by natural selection." But if such featured "evolutionary gems" are among the best that evolutionary scientists have to offer, which is what the packet implies, then that leaves a large gap between the observed data and Nature's grand claims.

Meanwhile, what treatment of microevolutionary changes would be complete without a discussion of Darwin's Galapagos finches? The packet explains that "When Charles Darwin visited the Galapagos Islands, he recorded the presence of several species of finch that all looked very similar except for their beaks," further noting that "Darwin speculated that all the finches had a common ancestor that had migrated to the islands." We've all heard this story before -- but is there more too it?

According to the British Natural History Museum, "Mockingbirds from the Galapagos Islands, not finches, gave Charles Darwin his ideas about evolution. ... Darwin's finches are the better-known birds connected with helping Darwin come to his conclusions on evolution. However, it was the little-known mockingbirds that were the key." Likewise, historian of science Frank Sulloway debunks the finch myth, stating that, "far from being crucial to his evolutionary argument, as the legend would have us believe, the finches were not even mentioned by Darwin in the Origin of Species." (See: Frank J. Sulloway, "Darwin and His Finches: The Evolution of a Legend," Journal of the History of Biology, Vol. 15(1):1-53 (Spring, 1982).)

Island Biogeography observes that it is "unclear whether [the mockingbird] genus (Nesomimus) is sufficiently distinct morphologically to warrant separation from the mainland genus (Mimus)" (Robert J. Whittaker, Island Biogeography: Ecology, Evolution, and Conservation, p. 96 (Oxford University Press, 1998)), or as Explore Evolution explains, the mockingbirds "show only small-scale variations in existing traits."

Setting aside Nature's perpetuation of common myths about the Galapagos finches, modern-day field studies of these finch species are commonly cited as examples of evolution. So again we must ask, How much evolutionary change are we talking about? Here, the packet is somewhat forthright, acknowledging that we're in fact only talking about "small differences in the depth, width or length of the beak." The packet then refers readers to a study that investigated the genetic basis of these small changes in beak morphology. It's an interesting paper, but as the packet explains, these changes in beak morphology may be caused by mere "differing expression of the gene for calmodulin, a molecule involved in calcium signaling that is vital in many aspects of development and metabolism." (See Arhat Abzhanov, Winston P. Kuo, Christine Hartmann, B. Rosemary Grant, Peter R. Grant,, and Clifford J. Tabin, "The calmodulin pathway and evolution of elongated beak morphology in Darwin's finches," Nature, Vol. 442:563-567 (August 3, 2006).)

So what's at issue here is mere differential expression of a gene (rather than the evolution of an entirely new gene) causing "small differences" in beak morphology. For the Darwin-critic, this is interesting since such differences in beak shape are well-known throughout a variety of bird groups (such as Hawaiian honeycreepers), making it unsurprising that commonly observed forms of biodiversity have a small-scale genetic basis. None of this suggests how large-scale evolutionary change could occur. While the origin of the beaks (and the birds) themselves may remain unexplained, perhaps diverse beak morphologies are designed to evolve.

Microevolution+Microevolution=?

Nature's Microevolutionary Gems Part 1: Lizards, Fish, Snakes, and Clams
Casey Luskin

Early in 2006, the journal Science published a long article titled "Evolution in Action" purporting to give three examples showing the glory of Darwinian evolution. As I discussed at that time, what it really showed was "microevolution in action." Last year during the bicentennial anniversary of Darwin's birth, Nature tried to top Science by releasing a packet titled "15 Evolutionary Gems." The packet purported to show "just what is the evidence for evolution by natural selection." Yet much like the Science piece, many of the examples in the Nature packet entail trivial examples of small-scale evolution. This first installment of Nature's "microevolutionary gems" will look at the evidence cited there for evolution among lizards, snakes, clams, and birds.
Size Matters in Stickleback fish and Anolis lizards
One of Nature's "gems" was said to show "Natural selection in speciation." The study cited found that reproductive isolation between different populations of stickleback fish was established based upon the trait of body size: "Levels of reproductive isolation are well accounted for by differences in a single trait, body size." Since body size can be determined by genes or the environment, it wasn't entirely clear whether the selected traits were heritable. In fact, when individuals from different stickleback populations were manipulated in the lab to the "preferred" body size of a different "ecotype" (e.g. a member of the same species from a different habitat), mating occurred even though the sticklebacks had previously been from different reproductively isolated populations.

While this study is a nice demonstration of how assortative mating can lead to sympatric speciation (so long as we define "speciation" as mere "reproductive isolation" and don't expect significant morphological change), what this shows is that even after untold generations of reproductive isolation, these fish are still reproductively compatible so long as they like the "size" of their partner. And what sort of morphological divergence is observed between the different stickleback populations? A difference of 2-3 centimeters in length. It goes without saying that small changes in the size of stickleback fish are not going to explain the evolution of sticklebacks in the first place. Have we really witnessed differences that show large-scale evolutionary change is possible, or even "speciation"?

(See Jeffrey S. McKinnon, Seiichi Mori, Benjamin K. Blackman, Lior David, David M. Kingsley, Leia Jamieson, Jennifer Chou & Dolph Schluter, "Evidence for ecology's role in speciation," Nature, 429:294-298 (May 20, 2004).)

Another "gem" claimed to find "Natural selection in lizards." Well, it wasn't exactly "natural" selection. Somewhat like the way researchers once glued peppered moth on trees to see if they'd be eaten by birds, evolutionary researchers artificially introduced a predatory lizard to small islands in the Caribbean to see if there was any impact upon populations of smaller Anolis lizards native to the islands. And they didn't just introduce the lizards to the island. They also artificially released "curly-tailed" predatory lizards right in front of their would-be prey, the lizard species Anolis sagrei, to see how Anolis lizards would respond. Here's what your taxpayer-funded NSF grant dollars supported:

On four of the experimental islands, we conducted focal animal observations on individual A. sagrei to investigate their immediate reaction to the introduction of curly-tailed lizards. Lizards were approached and an experimental object -- either a live curly-tailed lizard (n � 24) or, as a control, an inanimate object of approximately the same size (n � 23) -- was placed 0.5-1.0m from the lizard on the ground and clearly in its visual field.
(Jonathan B. Losos, Thomas W. Schoener & David A. Spiller, "Predator-induced behaviour shifts and natural selection in field experimental lizard populations," Nature 432:505-508 (November 25, 2004).)

That the experiment was not entirely "natural" is no great reason to criticize it and in fact it does serve as a nice illustration of what natural selection might be able to do. Confirming prior studies, the Anolis lizards were found to undergo selection for both larger body sizes (in females) and longer limb (in males) because this allowed them to better escape the predatory "curly-tailed" lizards. And Anolis lizards may be small but they aren't stupid: they also started spending less time on the ground and perched higher up in trees to escape their newfound predators. I'm sure that the slower, smaller Anolis lizards didn't appreciate falling prey (literally) to this experiment -- in Darwin's words, such experiments show "Nature red in tooth and claw" at its finest. But we've still seen nothing beyond extremely small-scale changes in lizard sizes. Much like the peppered moth story said nothing about the origin of moths, what does this study tell us about the origin of lizards? Not much.

Toxic Examples of Evolution
It's long been discussed by critics of neo-Darwinian that the evolution of antibiotic resistance entails the evolution of essentially no new functional biological information in the genome. Nature calls "Toxin resistance in snakes and clams" an "evolutionary gem," but what's really going on in the studies cited?

In the case of snakes, a species of garter snakes predate upon certain newts which produce the toxin tetrodotoxin (TTX). The toxin "causes paralysis and death by binding to the outer pore of voltage-gated sodium channels and blocking nerve and muscle fiber activity." It turns out that by substituting valine for isoleucine in a gene for a particular protein involved in the sodium ion channel, a small amount of resistance to TTX is gained. A couple other amino acid substitutions in certain snake species also seem to confer additional resistance. Meanwhile, the sodium ion channels continue to perform their functions. So we see that toxin-resistance requires small-scale genetic changes that entail the origin of no new genes.

(See Shana L. Geffeney, Esther Fujimoto, Edmund D. Brodie III, Edmund D. Brodie Jr, & Peter C. Ruben, "Evolutionary diversification of TTX-resistant sodium channels in a predator-prey interaction," Nature 434:759-763 (April 7, 2005).)

As for the clams, the packet reports that "Resistance to the toxin in the exposed populations is correlated with a single mutation in the gene that encodes a sodium channel, at a site already implicated in the binding of saxitoxin." (See V. Monica Bricelj, Laurie Connell, Keiichi Konoki, Scott P. MacQuarrie, Todd Scheuer, William A. Catterall & Vera L. Trainer, "Sodium channel mutation leading to saxitoxin resistance in clams increases risk of PSP," Nature 434:736-767 (April 7, 2005).)


In both cases, we're talking about strong selection pressure causing a couple changes (or even just one change) in the amino acid sequence of structural proteins. No new functions or structures are evolving and all we've seen is the loss of the ability of a toxin to bind to its target -- a protein involved in sodium channels. This is similar to the breaking down of a function -- losing the ability to bind through a mutation. Interesting and important research for sure, but if we're trying to showcase "just what is the evidence" for the grander claims of Darwinian evolution, this will not suffice.

Evaluating Darwinism's evangel

Evaluating Nature's 2009 "15 Evolutionary Gems" Darwin-Evangelism Kit
Casey Luskin 

Last year, during the bicentennial anniversary of Darwin's birth, Nature released a free online packet titled "15 Evolutionary Gems." Its subtitle was "A resource from Nature for those wishing to spread awareness of evidence for evolution by natural selection." It might have been better subtitled 'A evangelism packet for those wishing to spread the good news about Darwinism.' After all, when Nature announced the packet, they said they were heeding a prior call which "urged scientists and their institutions to 'spread the word'" about evolution and "highlight reasons why scientists can treat evolution by natural selection as, in effect, an established fact." The packet is to be used not just in schools, but also in home evangelism or relationship evangelism. At least, that's basically what Nature said:
This week we are following our own prescription. Readers will find at www.nature.com/evolutiongems a freely accessible resource for biologists and others who wish to explain to students, friends or loved ones just what is the evidence for evolution by natural selection. ... In a year in which Darwin is being celebrated amid uncertainty and hostility about his ideas among citizens, being aware of the cumulatively incontrovertible evidence for those ideas is all the more important. We trust that this document will help.
("Announcement: Evolutionary gems," Nature, Vol. 457 (January 1, 2009).)


If all that weren't enough, the back page of the packet shows a picture of a smiling young Darwin with animals flocking about him (lizards, birds, monkeys, flowers, sponges, turtles, etc.), much like the pictures of Jesus posing with lions and lambs on some cheesy religious tract. You have to see the packet to believe it:Should we be surprised that Nature -- one of the world's top scientific journals -- is promoting evolution in this fashion? The respected historian of evolution Peter J. Bowler explains that Nature itself was originally founded in the late 19th century by T. H. Huxley and others for the express purpose of promoting a "campaign" to support Darwinism:

By exploiting their position in this network, Huxley and his friends ensured that Darwinism had come to stay. (Ruse, 1979a). They controlled the scientific journals -- the journal Nature was founded in part to promote the campaign -- and manipulated academic appointments. Hull (1978) has stressed how important these rhetorical and political skills were in creating a scientific revolution. The Darwinists adopted a flexible approach which deflected opposition, minimized infighting among themselves, and made it easy for others to join their campaign. Many, like Huxley himself, were not rigidly committed to the theory of natural selection; they were simply anxious to promote the case for evolution.
(Peter J. Bowler, Evolution: The History of an Idea, p. 185 (University of California Press, 3rd ed., 2003).)

The packet is simply an extension of Nature's "campaign" for Darwin. But it is quite useful in one important respect: the packet is from the world's top scientific journal and purports to show us "just what is the evidence for evolution by natural selection." So if the evidence isn't very strong, then that should tell you something.

As we'll see, far from being "incontrovertible," most of the "evolutionary gems" in the packet do not show any significant amount of evolution and might be best views as "microevolutionary" gems. A couple of the "gems" have little to do with evolution, but an evolutionary interpretation is added in after-the-fact.

Finally, the few "gems" that do deal with large-scale change face serious problems and might be termed "lumps of coal." For the "lumps of coal," their strategy is the same: ignore dissent and overhype the evidence.

At the end of this series, all the posts will be combined into a single PDF file which can be downloaded and distributed or printed off freely.

An Evangelistic Opening
Nature's evolution-evangelism packet opens with one of the most dogmatic statements imaginable in support of evolution. According to the packet, "Most biologists take for granted the idea that all life evolved by natural selection over billions of years ... natural selection is a fact, in the same way that the Earth orbits the Sun is a fact." Surely, if their claim is true (and not a bluff) then we will find no notable scientific dissent from the view that "all life evolved by natural selection."

Just a couple years ago science journalist Susan Mazur (who is no friend of intelligent design) wrote that "hundreds of other evolutionary scientists (non-Creationists) who contend that natural selection is politics, not science, and that we are in a quagmire because of staggering commercial investment in a Darwinian industry built on an inadequate theory." Two of those scientists might be National Academy of Sciences members Philip Skell and Lynn Margulis, staunch critics of the claim that "all life evolved by natural selection":

"Darwinian evolution -- whatever its other virtues -- does not provide a fruitful heuristic in experimental biology. This becomes especially clear when we compare it with a heuristic framework such as the atomic model, which opens up structural chemistry and leads to advances in the synthesis of a multitude of new molecules of practical benefit. None of this demonstrates that Darwinism is false. It does, however, mean that the claim that it is the cornerstone of modern experimental biology will be met with quiet skepticism from a growing number of scientists in fields where theories actually do serve as cornerstones for tangible breakthroughs." -- Philip Skell
"[The] Darwinian claim to explain all of evolution is a popular half-truth whose lack of explicative power is compensated for only by the religious ferocity of its rhetoric. 
-- Lynn Margulis

And of course there's the 800+ scientists  scientists who have courageously signed a statement agreeing that they are skeptical of the creative power of natural selection: "We are skeptical of claims for the ability of random mutation and natural selection to account for the complexity of life. Careful examination of the evidence for Darwinian theory should be encouraged."

But there's a deeper point here. If the claim that "all life evolved by natural selection" is "a fact, in the same way that the Earth orbits the Sun," then shouldn't it be as self-evident as the fact that the Earth orbits the Sun? But no one is making packets to evangelize for heliocentrism -- because in that case the evidence is so overwhelming that no one of any consequence disagrees.

Nature's evolution-evangelism packet seems like a politically motivated attempt to spread the good news about Darwin. And given the power that the journal Nature wields within the scientific community, its dogmatic treatment of natural selection serves to stifle academic freedom and dissent from Nature's viewpoint. This leads me to suspect that the journal might overstate the evidential case for natural selection. Over the course of eight subsequent posts, we'll see just how far these "gems" actually go to support the view that "all life evolved by natural selection" is "a fact, in the same way that the Earth orbits the Sun" is a fact.