Tag Archives: Darwinian Evolution

Polemics

John C. Sanford’s genetic entropy hypothesis

4 Comments
Apologetics and the progress of science
Apologetics and the progress of science

JoeCoder sent me a recent peer-reviewed paper by John C. Sanford, so I’ve been trying to find something written by him at a layman’s level so I could understand what he is talking about. (I am just a software engineer, not an expert in genetics). His CV is posted at the Cornell University web page.

I found this 20-minute video of an interview with him, in which he explains his thesis:

The most important part of that video is Sanford’s assertion that natural selection cannot remove deleterious mutations from a population faster than they arrive.

And I also found a review of a book that he wrote that explains his ideas at the layman level.

It says:

Dr. John Sanford is a plant geneticist and inventor who conducted research at Cornell University for more than 25 years. He is best known for significant contributions to the field of transgenic crops, including the invention of the biolistic process (“gene gun”).

[…]Sanford argues that, based upon modern scientific evidence and the calculations of population geneticists (who are almost exclusively evolutionists), mutations are occurring at an alarmingly high rate in our genome and that the vast majority of all mutations are either harmful or “nearly-neutral” (meaning a loss for the organism or having no discernible fitness gain). Importantly, Sanford also establishes the extreme rarity of any type of beneficial mutations in comparison with harmful or “nearly-neutral” mutations. Indeed, “beneficial” mutations are so exceedingly rare as to not contribute in any meaningful way. [NOTE: “Beneficial” mutations do not necessarily result from a gain in information, but instead, these changes predominantly involve a net loss of function to the organism, which is also not helpful to [Darwinism]; see Behe, 2010, pp. 419-445.] Sanford concludes that the frequency and generally harmful or neutral nature of mutations prevents them from being useful to any scheme of random evolution.

[…]In the next section of the book, Sanford examines natural selection and asks whether “nature” can “select” in favor of the exceedingly rare “beneficial” mutations and against the deleterious mutations. The concept of natural selection is generally that the organisms that are best adapted to their environment will survive and reproduce, while the less fit will not. Sanford points out that this may be the case with some organisms, but more commonly, selection involves chance and luck. But could this process select against harmful mutations and allow less harmful or even beneficial mutations to thrive? According to Sanford, there are significant challenges to this notion.

Stanford is a co-author of an academic book on these issues that has Dembski and Behe as co-authors.

Now, I do have to post something more complicated about this, which you can skip – it’s an abstract of a paper he co-authored from that book:

Most deleterious mutations have very slight effects on total fitness, and it has become clear that below a certain fitness effect threshold, such low-impact mutations fail to respond to natural selection. The existence of such a selection threshold suggests that many low-impact deleterious mutations should accumulate continuously, resulting in relentless erosion of genetic information. In this paper, we use numerical simulation to examine this problem of selection threshold.

The objective of this research was to investigate the effect of various biological factors individually and jointly on mutation accumulation in a model human population. For this purpose, we used a recently-developed, biologically-realistic numerical simulation program, Mendel’s Accountant. This program introduces new mutations into the population every generation and tracks each mutation through the processes of recombination, gamete formation, mating, and transmission to the new offspring. This method tracks which individuals survive to reproduce after selection, and records the transmission of each surviving mutation every generation. This allows a detailed mechanistic accounting of each mutation that enters and leaves the population over the course of many generations. We term this type of analysis genetic accounting.

Across all reasonable parameters settings, we observed that high impact mutations were selected away with very high efficiency, while very low impact mutations accumulated just as if there was no selection operating. There was always a large transitional zone, wherein mutations with intermediate fitness effects accumulated continuously, but at a lower rate than would occur in the absence of selection. To characterize the accumulation of mutations of different fitness effect we developed a new statistic, selection threshold (STd), which is an empirically determined value for a given population. A population’s selection threshold is defined as that fitness effect wherein deleterious mutations are accumulating at exactly half the rate expected in the absence of selection. This threshold is mid-way between entirely selectable, and entirely unselectable, mutation effects.

Our investigations reveal that under a very wide range of parameter values, selection thresholds for deleterious mutations are surprisingly high. Our analyses of the selection threshold problem indicate that given even modest levels of noise affecting either the genotype-phenotype relationship or the genotypic fitness-survival-reproduction relationship, accumulation of low-impact mutations continually degrades fitness, and this degradation is far more serious than has been previously acknowledged. Simulations based on recently published values for mutation rate and effect-distribution in humans show a steady decline in fitness that is not even halted by extremely intense selection pressure (12 offspring per female, 10 selectively removed). Indeed, we find that under most realistic circumstances, the large majority of harmful mutations are essentially unaffected by natural selection and continue to accumulate unhindered. This finding has major theoretical implications and raises the question, “What mechanism can preserve the many low-impact nucleotide positions that constitute most of the information within a genome?”

If you think all this is interesting, there is a much longer lecture here, which I have not watched. JoeCoder has watched it and he endorses it.

Now I have been told by JoeCoder that there are many critical responses to his hypothesis, most of which have to do with whether natural selection can overcome the difficulty he is laying out. But since this is not my area of expertise, there is not much I can say to adjudicate here, I won’t be able to respond to these. I hope that I will have time to come back to this and read about it at some point. I do have an e-book of the that collection of papers book I linked to above.

Positive arguments for Christian theism

Polemics

Is there a smooth pathway from micro-evolution to macro-evolution?

6 Comments

From Luke Nix who blogs at Faithful Thinkers.

Excerpt:

Macroevolutionary changes are a lot of microevolutionary changes, but they are in a specific series that follow a specific pathway. The missing premise in this argument is that the pathway from ancestor to claimed offspring (many generations down the road) is clear of obstacles.

In his book, “The Edge of Evolution” Michael Behe shows that scientists have observed such an obstacle in the lab. The obstacle was not time, it is in the genetic pathway that must be traversed if macroevolutionary changes are to take place in reality. Since an obstacle has been observed, we now have a false premise in the argument. Since there is a false premise, the argument fails. There is a difference between micro- and macro-evolutionary changes. A lot of microevolutionary changes are necessary for macroevolution, but they are not sufficient. The other sufficient condition (a clear genetic pathway) still has yet to be met. Since both sufficient conditions for macroevolution have not been met, it has not been demonstrated. And since changes over time has been demonstrated, there is a need to distinguish between the two. To prevent confusion about what we know to be true and what we don’t, this distinction must be made.

There is only one way that this can be overcome by the naturalist: find a pathway that would be clear by default in nature. Notice that I have added one more piece to the missing premise above: “…clear by default in nature“. I have to add that last qualification because as scientists are looking for a way to overcome this obstacle, they are introducing their own intelligence- fine-tuning the process, then “allowing nature to take its course”. Their conclusion of naturalistic macroevolution will depend on a premise that is founded on intelligence. That would undermine the whole argument for naturalistic (macro)evolution.

This is one of the ways to show that evolution is true – by showing a pathway to macro-evolutionary change in the lab. If people expect me to believe in the grandiose claims of fully naturalistic evolution through a stepwise process, then why can’t I see the pathway myself? If you make the claim that it happened, then I want to see the evidence for the claim.

Related posts

Videos

Is Darwinian evolution compatible with belief in God and robust religion?

Leave a comment

Here’s Casey Luskin to explain the facts about God and evolution: (21 minutes)

About Casey Luskin: (just a snippet)

Casey Luskin is an attorney with graduate degrees in both science and law. He earned his B.S. and M.S. in Earth Sciences from the University of California, San Diego. His Law Degree is from the University of San Diego. In his role at Discovery Institute, Mr. Luskin works as Research Coordinator for the Center for Science and Culture. He formerly conducted geological research at Scripps Institution for Oceanography (1997-2002).

Luskin is also co-founder of the Intelligent Design and Evolution Awareness (IDEA) Center, a non-profit helping students to investigate evolution by starting “IDEA Clubs” on college and high school campuses across the country. For his work with IDEA, the Intelligent Design and Undergraduate Research Center named an award honoring college graduates for excellence in student advocacy of intelligent design (ID) the “Casey Luskin Graduate Award.”

If you can’t see the video, then you can check out this article by Casey from Salvo magazine.

Excerpt:

Whenever someone avers belief in “God-guided evolution,” it’s important to clarify what is meant by “evolution.” It can mean something as benign as (1) “Life has changed over time,” or it can entail more controversial ideas, like (2) “All living things have a universal common ancestry,” or (3) “Natural selection acting upon random mutations produced the complexity of life.”

When the average theistic evolutionist says he believes that “God used evolution,” what he often actually means is that God supernaturally intervened at various points in Earth’s history to direct the course of life. He accepts evolution in sense 1 above, and maybe sense 2 as well, but has doubts about sense 3. This viewpoint differs dramatically from the standard neo-Darwinian paradigm that currently reigns in biology.

As defined by its proponents, neo-Darwinism is a blind process of natural selection acting upon random mutations without any guidance by an external agent. According to the architects of this theory, the evolutionary process has no goals or predetermined outcome, and is by definition unguided. Under this view of life, human beings are accidents of history—and not just their bodies, but their brains and behaviors as well, including their moral and religious impulses. Thus, true neo-Darwinian theistic evolutionists (and they are out there) claim that, somehow, God guided an unguided process.

But many of those who adopt the “theistic evolutionist” moniker actually reject neo-Darwinism and hold a view that’s much closer to intelligent design, that is, to the belief that an intelligent agent has actively intervened—in a meaningful and detectable manner—to guide the development of life. The Evolution Lobby, however, will never be satisfied until such people fully capitulate to the Darwinian view.

And a bit later in that same paper:

Evolutionary biologist Francisco Ayala makes this argument, stating, “Mutations are random or chance events because . . . [they] are unoriented with respect to adaptation.”

[…]Ayala continues:

The scientific account of these events does not necessitate recourse to a preordained plan, whether imprinted from the beginning or through successive interventions by an omniscient and almighty Designer. Biological evolution differs from a painting or an artifact in that it is not the outcome of preconceived design.

Ayala concludes that, “in evolution, there is no entity or person who is selecting adaptive combinations.”12 Again, that doesn’t sound like a religiously neutral model of biological origins.

Indeed, in surveying how mainstream biology textbooks define Darwinian evolution, we learn it is a “random,” “blind,” “uncaring,” “heartless,” “undirected,” “purposeless,” and “chance” process that acts “without plan” or “any goals”; that we are “not created for any special purpose or as part of any universal design,” and that “a god of design and purpose is not necessary.”13 If those don’t entail claims that cut against theism, what would?

Moreover, if Darwinian evolution is irrelevant to faith, why do so many atheists cite it as a reason for abandoning religion? A 2007 poll of 149 evolutionary biologists found that only two “described themselves as full theists.”14 Likewise, a survey of biologist members of the NAS found that over 94 percent were atheists or agnostics.15 It’s no coincidence that Eugenie Scott—the de facto head of the Evolution Lobby—signed the Third Humanist Manifesto, or that the world’s most famous evolutionary biologist, Richard Dawkins, is also the world’s most famous atheist. In Dawkins’s own words, “Darwin made it possible to be an intellectually fulfilled atheist.”16

He is one of my favorite people to listen to, because he is very very direct and definitely is not clouding the issues, the combatants and what each side is really trying to achieve. There is a lot of noise and obfuscation in this debate. But if you watch Casey’s video, you will get everything as it really is.