Evolution: World science academies fight back against creationists

PhysOrg.com ^ | 21 June 2006 | Staff

[PatrickHenry]

In a veiled attack on creationism, the world's foremost academies of science on Wednesday called on parents and teachers to provide children with the facts about evolution and the origins of life on Earth.

A declaration signed by 67 national academies of science blasted the scriptural teaching of biology as a potential distortion of young minds.

"In various parts of the world, within science courses taught in certain public systems of education, scientific evidence, data and testable theories about the origins and evolution of life on Earth are being concealed, denied or confused with theories not testable by science," the declaration said.

"We urge decision-makers, teachers and parents to educate all children about the methods and discoveries of science and to foster an understanding of the science of nature.

"Knowledge of the natural world in which they live empowers people to meet human needs and protect the planet."

Citing "evidence-based facts" derived from observation, experiment and neutral assessment, the declaration points to findings that the Universe is between 11 and 15 billion years old, and the Earth was formed about 4.5 billion years ago.

Life on Earth appeared at least 2.5 billion years ago as a result of physical and chemical processes, and evolved into the species that live today.

"Commonalities in the structure of the genetic code of all organisms living today, including humans, clearly indicate their common primordial origin," it said.

Signatories of the declaration include the US National Academy of Sciences, Britain's Royal Society, the French Academy of Sciences and their counterparts in Canada, China, Germany, Iran, Israel and Japan and elsewhere.

The statement does not name any names or religions, nor does it explain why it fears the teaching of evolution or the scientific explanation for the origins of planetary life are being sidelined.

It comes, however, in the context of mounting concern among biologists about the perceived influence of creationism in the United States.

Evangelical Christians there are campaigning hard for schools to teach creationism or downgrade evolution to the status of one of a competing group of theories about the origins of life on Earth.

According to the website Christian Post (www.christianpost.com), an opinion poll conducted in May by Gallop found that 46 percent of Americans believe that God created humans in their present form within the last 10,000 years or so.

Scientists say hominids emerged around six million years ago and one of their offshoots developed into anatomically modern man, Homo sapiens, about 200,000 years ago, although the timings of both events are fiercely debated.

Nearly every religion offers an explanation as to how life began on Earth.

Fundamentalist Christians insist on a literal interpretation of the Book of Genesis in the Bible, in which God made the world in seven days, culminating in the creation of the first two humans, Adam and Eve.

A variation of this is called "intelligent design" which acknowledges evolution but claims that genetic mutations are guided by God's hand rather than by Charles Darwin's process of natural selection.

US President George W. Bush said last August that he believed in this concept and that he supported its teaching in American schools.

The academies' statement says that science does not seek to offer judgements of value or morality, and acknowledges limitations in current knowledge.

"Science is open-ended and subject to correction and expansion as new theoretical and empirical understanding emerges," it adds.

[Diamond]

...the contention made by Behe is quite different from this – it is that evolution cannot explain the flagellum in principle (because its multiple components have no selectable function). By demonstrating the existence of such functions, even in just a handful of components, we have invalidated the argument.

1. Note the tacit abandonment of classical Darwinian direct evolution along a linear axis in the attempt explain these machines.

2. The ability to imagine such alternate funtions is not evidence that they existed. Is there any reason to suspect these alternate functions really existed, and are not just vague, ad hoc appeals to cooption?

3. The appeal to raw chance necessary to the coicidental cooption of alternative functions removes the explantory power:

3. Cooption of Alternative Function (CAF)

This explanation best exploits the logical flaw in the "IC = evolution is impossible" argument. That is, since the existence of A, B, C, and D need not be F-dependent, CAF simply proposes that A, B, C, and D did indeed exist prior to F, whereby these components performed some alternative, original function. As such, this is really the only evolutionary explanation that has the potential to explain the origin of an IC system. Thus, let's take a closer look at it.

This explanation would look as follows:

 

where G, H, I, and F are functions that previously employed components A, B, C, and D, respectively. A, B, C, and D could be directly donated into the newly formed IC system if functions G - J become disposable. Or, a gene duplication may occur for each of the gene products, allowing the duplicates to be recruited into the newly formed IC system. Or, gene products A - D could exist and now carry out dual roles in the cell.

 

While such a scenario provides a working explanation for the origin of the IC system, a serious investigator will want to know if there is reason to think this scenario is relevant to the origin of any particular IC system in question (the mere ability to imagine such scenarios is not evidence that such a scenario happened). Put simply, we need evidence to think this scenario applied.

Back in 1997, Julie Thomas posted an analysis of IC to the talk.origins newsgroup that is relevant here. Thomas describes what is needed when considering component (player) C, but keep in mind the same analysis would apply for A, B, and D:

---

However, in order for alternative activity to pose a serious challenge to the IC status of actual player C, several things must be demonstrated:

1. Evidence must exist that indicates the similar activity is older. Since this explanation proposes the acquisition of function F after the existence of the similar activity, alternative activity fails as an objection to IC if the similar activity post-dates function F. Put simply, the secondary activity must reflect a more ancient state and not a recent by-product of actual player C's role.

2. The similar activity should exist at biologically relevant states. This is important as in vitro evidence can be misleading. For example, if actual player C is a DNA-binding protein, but binds to RNA in the test tube under conditions that are not seen in the cell, the similar activity is biologically suspect and may simply be an artifact of the unnatural in vitro conditions.

3. Is the alternative activity present in the organism with the IC system in question? Similar activities, detected by in vitro tests using extracts from two very different organisms is of questionable biological relevance since the lineage of the organism with the IC system in question may have never possessed anything like the alternative activity.

4. The similar activity should not be part of another IC system. Otherwise, the argument travels in a circle. For example, single-stranded binding (ssb) proteins are involved in DNA replication and DNA recombination. If one explains away the role of ssb proteins in replication by appealing to recombination, yet explains away the role of ssb proteins in recombination by appealing to replication, we have gotten nowhere and have only the appearance of a refutation of actual player C's role in an IC system.

Such analyses will go a long way in resolving IC claims. If the similar activity post-dates player C's role, it fails as an explanation. If it is found only in test tube assays, the explanation is severely weakened. If the similar activity is part of another IC system, the original role may be in question, but some IC role remains.

---

However, even if a particular system successfully overcomes these obstacles, it is not clear CAF applies. CAF makes an assumption about cell biology than is increasingly untenable, namely that the cell is basically a soup. This soupy aspect of the cell is needed for A, B, C, and D to escape their original functional states in order to fortuitously interact. Yet it is becoming increasingly clear than many machine components are assembled into the complex very quickly after being synthesized and/or targeted to specific sites of assembly. For example, it's becoming more and more clear that certain metabolic enzymes are secured in various places and interact as tightly fitting complexes that directly hand-off product/substrate. Where they are found and how they are arranged is just as important as their existence. This was beautifully illustrated with some mutant work in Drosophila that showed a specific glycolytic isozyme was required for flight, as the existence of another isozyme was not functional due to its mislocation. As one reviewer of this study commented, "The presence of catalytically functional proteins alone is therefore not adequate; they must be properly located." Therefore, for the CAF scenario to work, the alternative function should not anchor the component-to-be-borrowed and if it does, some cellular change must be invoked to liberate it.

Yet the most basic problem with CAF is its complete reliance on chance. If we return to the originally proposed pathway above, we are asked to believe that while A, B, C, and D have long been shaped by selection to carry out their original alternative functions, a fortuitous interaction among them all would spontaneously emerge a brand new function. Selection might be invoked to fine-tune and improve this new function, but the bottom line remains in that raw chance is being credited for the creation of a novel function. I explained this elsewhere as follows:

"Co-option is the most commonly cited non-teleological means to generate an IC system. Yet, it is essentially a return to raw coincidence to account for apparent design. The brilliance of Darwin was to minimize the role of chance in apparent design. But once we turn to the co-option explanation, we leave this explanatory appeal behind, as chance reasserts itself into a place of prominence. For it is chance that determines whether the various gene products just happen to come together to form a new functioning system, as selection was previously pruning these gene products in accord with various different functions. If one is to invoke co-option, good supporting evidence is required."

The problem of invoking chance to explain the origin of a new function is quite serious when dealing with IC molecular machines. For these machines to work, their components are usually tightly fitted into a whole through the interactions of their complementary conformations. It would be unlikely for four various proteins, pruned by selection to carry out their original functions, just happened to have sufficient conformational complementarity to assemble into a novel machine with a novel function (which explains why no one has ever observed cooption to spawn a new molecular machine). Unless, of course, certain machines were designed to channel evolution by cooption, meaning that certain cooption events were rigged to occur...

IC revisited

Cordially,

[js1138]

1. Evidence must exist that indicates the similar activity is older.

Nonsense. ID irreducible complexity asserts that subcomponents cannot have a function that could be subject to selection. Everything else in your argument is simply a restatement that not everything is known -- something already stipulated.

The basic problem with ID is that it doesn't propose any mechanisms for change that can be tested. It just points at yet unknown areas and says, "There be dragons."

[Diamond]

ID irreducible complexity asserts that subcomponents cannot have a function that could be subject to selection.

No it doesn't. It doesn't stipulate whether subcomponents may have or had an alternate selective function or not. All IC means, as Dembski has pointed out, is that "a functional system is irreducibly complex if it contains a multipart subsystem (i.e., a set of two or more interrelated parts) that cannot be simplified without destroying the system’s basic function." He goes on to define the core of a functionally integrated system as those parts that are indispensable to the system’s basic function.

The question is, even granting for the sake of argument the existence of components that have long been shaped by selection to carry out their original alternative functions, exactly how could a fortuitous interaction among them all spontaneously create a brand new function? It's not just the metabolic pathways - its the ASSEMBLY process that presents huge difficulties for a Darwinian mechanism, ie, by "numerous, successive, slight modifications.", because the process of assembly itself in the right sequence and timing requires other regulatory machines, so is in itself irreducibly complex.

Cordially,

[js1138]

exactly how could a fortuitous interaction among them all spontaneously create a brand new function?

For an example, check out the evolution of the ear bones.

In the case of the flagellum, the lack of a ready answer does not argue for the existence of invisible pink unicorns.

[Diamond]

...the lack of a ready answer does not argue for the existence of invisible pink unicorns.

I thought the appeal of Darwinism was its explanatory power.

Besides, why should someone skeptical of the attribution of causal power of natural selection to build a molecular machine like the flagellum be absurdly required to prove an impossibilty when the proposition that not only could the BF be formed by a fully detailed series of slight modifications, but actually was formed that way historically completely without any empirical support, and when the burden is on the Darwinist who asserts it to demonstrate it empirically in the first place?

Cordially,

[js1138]

The assumption of natural causes does not provide instant answers to forensic questions. Unsolved forensic puzzles do not imply magic.

The assumption of magic leads nowhere.