Tag Archives: Darwinism

Are the Galapagos finch beaks evidence of Darwinian evolution?

I have a key that will unlock a puzzling mystery
I have a key that will unlock a puzzling mystery

Jonathan Wells has an article about it at Evolution News.

It says:

When Charles Darwin visited the Galápagos Islands in 1835, he collected specimens of the local wildlife. These included some finches that he threw into bags, many of them mislabeled. Although the Galápagos finches had little impact on Darwin’s thinking (he doesn’t even mention them in The Origin of Species), biologists who studied them a century later called them “Darwin’s finches” and invented the myth that Darwin had correlated differences in the finches’ beaks with different food sources (he hadn’t). According to the myth, Darwin was inspired by the finches to formulate his theory of evolution, thoughaccording to historian of science Frank Sulloway “nothing could be further from the truth.”

In the 1970s, biologists studied a population of medium ground finches on one of the islands in great detail. When a severe drought left only large, hard-to-crack seeds, 85 percent of the birds perished. The survivors had beaks that were about 5 percent larger than the average beak size in the original population. The biologists estimated that if similar droughts occurred once every ten years, the population could become a new species in only 200 years. In a 1999 booklet defending evolution, the U.S. National Academy of Sciences called the finches “a particularly compelling example” of the origin of species.

But after the drought, birds with smaller beaks flourished again, and the average beak size of the population returned to normal. No net evolution had occurred. No matter; Darwin’s finches became an icon of evolution that is still featured in most biology textbooks.

In the 1980s, a population of large ground finches, with larger beaks than the medium ground finches, migrated to the island. When a drought in 2004-2005 again reduced the food supply, the medium and large ground finch populations both declined. But since even the largest beaks among the medium ground finches were no match for the beaks of the large ground finches, the latter pretty much monopolized the larger seeds and the former had to make do with smaller seeds. This time, the medium ground finches that survived the drought had beaks that were smaller than the average size in the original population. Biologists studying the finches argued that birds with smaller beaks were better able to eat the tiny seeds that were left after the large ground finches ate the big ones, and they concluded that this was again an example of “evolutionary change.”

[…]Wait a minute. Average beak size increased slightly during one drought, only to return to normal after the rains return. Then average beak size decreased slightly during another drought. A region of DNA is correlated with beak size. And somehow that tells us how finches evolved in the first place?

There is an important distinction to make between micro-evolution and macro-evolution. Changes within a type is micro-evolution. Evolving a new organ type or body plan is macro-evolution. There is plenty of evidence for micro-evolution, but no evidence for macro-evolution.

What needs to be proven by the Darwinists is that the same process that results in different average beak size in a population of finches after a drought can create the finches in the first place. I think that Darwinists are credulous – they believe what they want to believe because they want to believe it, even if the evidence is incredibly weak. Darwinists must demonstrate that heritable variations can result in the generation of new organ types and body plans. Changes in average beak size is not interesting. What is needed is to show how the beaks, much less the wings, evolved in the first place.

Icons of Evolution

Jonathan has actually written about a number of  misleading things that you may mind in Biology textbooks.

Here are the sections in his book “Icons of Evolution“:

  • The Miller-Urey Experiment
  • Darwin’s Tree of Life
  • Homology in Vertebrate Limbs
  • Haeckel’s Embroys
  • Archaeopteryx–The Missing Link
  • Peppered Moths
  • Darwin’s Finches
  • Four-Winged Fruit Flies
  • Fossil Horses and Directed Evolution
  • From Ape to Human: The Ultimate Icon

Dr. Wells holds a Ph.D in Molecular and Cell Biology from the University of California at Berkeley.

Biomimetics again: scientists reverse engineer the design of snake scales

Christianity and the progress of science
Christianity and the progress of science

Today, I have an example of biomimetics.

But first, here’s what that is:

Biomimetic refers to human-made processes, substances, devices, or systems that imitate nature. The art and science of designing and building biomimetic apparatus is called biomimetics, and is of special interest to researchers in nanotechnology, robotics, artificial intelligence (AI), the medical industry, and the military.

This is from Science Daily. (H/T Fuz Rana)

It says:

A snake moves without legs by the scales on its belly gripping the ground. It generates friction at the points needed to move forwards only and prevents its scales from being worn off by too much friction. Researchers of KIT have found a way to transfer this feature to components of movable systems. In this way, durability of hip prostheses, computer hard disks or smartphones might be enhanced.

“Friction and wear are two of the biggest challenges in systems of several individual components,” Christian Greiner of the Institute for Applied Materials says. A solution is found in nature: Snakes, such as the ball python, or lizards, such as the sandfish skink, use friction to move forwards, but can reduce it to a minimum thanks to their scales. Together with Michael Schäfer, Greiner developed a process to transfer the scale structure of reptiles to components of electromechanical systems: With a fiber laser, they milled scales into a steel bolt of 8 mm in diameter.

With the help of two different structures, the materials researchers tested whether the distance of the scales influences friction behavior. In the first structure, the scales overlap and are located very closely to each other, such as the scales on the belly of a ball python. The second structure consists of scales arranged in vertical rows at a larger distance, such as the skin of a sandfish skink. “The distance between the rows in our experiment was the smallest possible distance we could produce with the laser. The structure, hence, does not entirely correspond to that of the sandfish skink,” Greiner says. In the future, however, the researchers plan to produce structures that are closer to the original in nature.

[…]To find out whether scales reduce friction, Greiner and Schäfer fixed the structured surface of the bolts to a rotating plate. The experiments were carried out without and with a lubricant (1 ml of mineral oil). For the experiments with oil as lubricant, the scientists used steel disks. Under dry sliding conditions, sapphire disks were applied. The disk diameter was 50 mm.

Experiments under lubricated conditions revealed that both narrow and wide arrangements of the scales increase friction compared to the unstructured bolt: By the wide scales, friction is increased by a factor of 1.6. The narrow scales increase friction by a factor of 3. In the non-lubricated state, the wide scale structure reduced friction by more than 40 percent, while friction was reduced by 22 percent in case of a narrow scale structure.

The finding that the narrow scale structure increases friction under both lubricated and non-lubricated conditions had not been expected by the researchers: “We assumed that the narrow structure is more effective, as it is closer to nature,” Greiner says.

See the related posts for more examples of humans learning from the engineering designs in nature.

Related posts

What difference does believing in evolution make?

Investigation in progress
Investigation in progress

In this post, the word evolution refers to the theory that unguided natural forces such as mutation and natural selection can explain the emerge of life from non-life, as well as the diversification of simple single-celled organisms in the diversity of animal life that we observe today, and in the fossil record. mean merely change over time, or variations within types “micro-evolution”. I mean molecules-to-man evolution, with nothing detectable done to guide any part of the process by any outside intelligence, be it natural or supernatural.

What else do people believe when they accept evolution as true?

Evolution News reports on a new poll:

From the earliest days of civilization, humans have considered themselves exceptional among living creatures. But a new survey by Discovery Institute of more than 3,400 American adults indicates that the theory of evolution is beginning to erode that belief in humanity’s unique status and dignity.

According to the survey, 43 percent of Americans now agree that “Evolution shows that no living thing is more important than any other,” and 45 percent of Americans believe that “Evolution shows that human beings are not fundamentally different from other animals.”

The highest levels of support for the idea that evolution shows that humans aren’t fundamentally different from other animals are found among self-identified atheists (69 percent), agnostics (60 percent), and 18 to 29 year-olds (51 percent).

The theory of evolution is also reshaping how people think about morality. A majority of Americans (55 percent) now contend that “Evolution shows that moral beliefs evolve over time based on their survival value in various times and places.”

“Since the rise of Darwin’s theory, leading scientists and other thinkers have insisted that human beings are just another animal, and that morality evolves based on survival of the fittest,” says historian Richard Weikart, author of the new book The Death of Humanity: And the Case for Life (Regnery).

What this new survey shows is just how pervasive these ideas have become in our culture. Many people no doubt continue to believe that humans are unique, but most do not think that evolution supports that position. Many critics of my earlier scholarship will be disconcerted to see this data, which powerfully supports my arguments about the way that Darwinism devalues human life, a key point I explain further in my new book.

Weikart is a professor of history at California State University, Stanislaus, and a Senior Fellow with Discovery Institute’s Center for Science & Culture.

So, it definitely makes  a difference whether you believe in evolution or not. I have found that even Christians who believe in evolution have some very weird things going on elsewhere in their worldviews. Let’s just say that I don’t know any conservative Christians who accept evolution.

Take a look at Howard Van Till, who taught at a seminary for many years. He always asserted that evolution and Christianity were compatible. That’s what he told his students. He was regarded as one of the foremost proponents of theistic evolution – the view that God exists and sits around doing nothing while animal diversity appears without any detectible design work on his part.

Take a look at this event that Van Till did for a FREETHOUGHT group a while back.

Excerpt:

FROM CALVINISM TO FREETHOUGHT: The Road Less Traveled
by Howard J. Van Till

Professor of Physics and Astronomy, Emeritus
Calvin College
Presented 5/24/2006 for the Freethought Association of West Michigan
Lightly edited 5/26/2006

Precis: Born into a Calvinist family, shaped by a Calvinist catechism training, educated in the Calvinist private school system, and nurtured by a community that prized its Calvinist systematic theology, I was a Calvinist through and through. For 31 years my teaching career was deeply rooted in the Calvinism I had inherited from my community.

During most of that time it was a fruitful and satisfying experience. Nonetheless, stimulated in part by the manner in which some members of that community responded to my efforts to practice what I had learned from my best teachers, I eventually felt the need to extend my intellectual exploration into philosophical territories far outside the one provided by Calvinism. Did I complete the lengthy journey from Calvinism to Freethought? The listener will be the judge.

Freethought is a politically correct happy-clappy term for atheism, by the way. Trying to put a positive spin on it, I guess.

Evolution means unguided evolution. It means that natural processes do all the work, and there is nothing required from any supervening intelligence – natural or supernatural. That idea has consequences for your worldview.

One last point, and this is important. I don’t reject evolution because I find the consequences of the idea distasteful. I reject it because it is not supported by the evidence in two crucial areas: the origin of the simplest living replicating organism, and the sudden appearance of a wide variety of body plans in the Cambrian explosion within a very short period of time. I have no problem with science challenging my interpretation of the Bible – that’s why I am for an old universe and an old Earth. But evolution is not scientifically grounded – it’s really a philosophical speculation that is required by a metaphysical assumption called naturalism. And since I am an adherent of experimental science, and not theoretical speculative philosophy, I reject it. And so should you.

Related posts

 

New study: natural selection can act to impede speciation

Australian Walking Stick
Australian Walking Stick

My friend KL sent me this press release from the University of Colorado at Boulder.

It says:

An intriguing study involving walking stick insects led by the University of Sheffield in England and the University of Colorado Boulder shows how natural selection, the engine of evolution, can also impede the formation of new species.

The team studied a plant-eating stick insect species from California called Timema cristinae known for its cryptic camouflage that allows it to hide from hungry birds, said CU-Boulder Assistant Professor Samuel Flaxman. T. cristinae comes in several different types — one is green and blends in with the broad green leaves of a particular shrub species, while a second green variant sports a white, vertical stripe that helps disguise it on a different species of shrub with narrow, needle-like leaves.

While Darwinian natural selection has begun pushing the two green forms of walking sticks down separate paths that could lead to the formation of two new species, the team found that a third melanistic, or brown variation of T. cristinae appears to be thwarting the process, said Flaxman. The brown version is known to successfully camouflage itself among the stems of both shrub species inhabited by its green brethren, he said.

Using field investigations, laboratory genetics, modern genome sequencing and computer simulations, the team concluded the brown version of T. cristinae is shuttling enough genes between the green stick insects living on different shrubs to prevent strong divergent adaptation and speciation. The brown variant of the walking stick species also is favored by natural selection because it has a slight advantage in mate selection and a stronger resistance to fungal infections than its green counterparts.

“This is one of the best demonstrations we know of regarding the counteractive effects of natural selection on speciation,” said Flaxman of CU-Boulder’s Department of Ecology and Evolutionary Biology, second author on the new study. “We show how the brown population essentially carries genes back and forth between the green populations, acting as a genetic bridge that causes a slowdown in divergence.”

A paper on the subject appeared in a recent issue of the journal Current Biology. 

[…]“This movement of genes between environments slows down the genetic divergence of these stick insect populations, impeding the formation of new species,” said Aaron Comeault, a former CU-Boulder graduate student and lead study author who conducted the research while at the University of Sheffield.

So, in the past I had read that natural selection can act as a stabilizing force in nature – keeping the organism operating within a type. This study seems to be confirmation of that. That’s a problem for naturalists, who believe that mutations and selection can drive evolution of new body plans or organ types (macro-evolution). I could even agree that mutation and selection drives changes within a kind, but that still wouldn’t explain how one kind changes into another kind.

But there are other problems with generating macro-evolutionary change.

Also related to the problem raised by the study is this problem of genetic drift, which also works against the preservation of beneficial mutations.

Evolution News explains the genetic drift problem:

Evolutionary biologists often assume that once mutations produce a functionally advantageous trait, it will easily spread (become “fixed”) throughout a population by natural selection. For example, imagine a population of brown-haired foxes that lives in a snowy region. One fox is born with a mutation that turns its fur coat white, rather than brown. This fox now has an advantage in hunting prey and escaping predators, because its white fur provides it with camouflage. The white fox survives, passing its genes on to its offspring, which are also adept at surviving and reproducing. Over time, the white-haired trait spreads throughout the population.

This is how it’s supposed to work — in theory. In the real world, however, merely generating a functionally advantageous trait does not guarantee it will persist, or become fixed. For example, what if by chance the white fox trips, breaks a leg, and gets eaten by a predator — never passing on its genes? Random forces or events can prevent a trait from spreading through a population, even if it provides an advantage. These random forces are lumped together under the name “genetic drift.” When biologists run the mathematics of natural selection, they find that unless a trait gives an extremely strong selective advantage, genetic drift will tend to overwhelm the force of selection and prevent adaptations from gaining a foothold in a population.

This underappreciated problem has been recognized by some evolutionary scientists who are skeptical of the ability of natural selection to drive the evolutionary process. One of those scientists is Michael Lynch, an evolutionary biologist at Indiana University, who writes that “random genetic drift can impose a strong barrier to the advancement of molecular refinements by adaptive processes.”2 He notes that the effect of drift is “encouraging the fixation of mildly deleterious mutations and discouraging the promotion of beneficial mutations.”3

I guess the point of this is that if someone wants to convince you that macro-evolution is possible through the mechanisms of random mutation and natural selection, then they have some work to do. And it’s more work than just asserting that it happened.

People who are technical may benefit from reading Michael Behe’s book “The Edge of Evolution”, which studies how likely it is to get several positive adaptations in a row within a reasonable period of time.

UPDATE: A biologist friend tells me that “whether natural selection is driving speciation or preventing it, in neither case is it explaining how these organisms came to be in the first place. It only explains how existing organisms interact with their environment. And this can be explained at least as well through intelligent design as through naturalistic processes.” She also says that natural selection can drive speciation, but still within a kind.

Stephen C. Meyer debates Charles Marshall on the Cambrian explosion

Christianity and the progress of science
Christianity and the progress of science

Here is a summary of recent podcast of Unbelievable between intelligent design proponent Stephen C. Meyer and UC Berkeley evolutionary biologist Charles Marshall. Dr. Marshall had previously reviewed Dr. Meyer’s new book “Darwin’s Doubt” in the prestigious peer-reviewed journal “Science”.

Details:

Stephen C Meyer is the world’s leading Intelligent Design proponent. His new book Darwin’s Doubt claims that the Cambrian fossil record, which saw an “explosion” of new life forms in a short space of time, is evidence for ID.

Evolutionary biologist Charles Marshall of the University of California, Berkeley has written a critical review of the book. He debates Meyer on whether Darwinian evolution can explain the diversity of life in the Cambrian rocks.

For Meyer & Darwin’s Doubt:
http://www.darwinsdoubt.com/

For Charles Marshall’s review:
http://www.sciencemag.org/content/341/6152/1344.1.full

You can get the MP3 file here.

The brief summary this time is not provided by me, it’s from Evolution News.

Excerpt:

This past weekend Britain’s Premier radio network broadcast a debate between Stephen Meyer and UC Berkeley paleontologist Charles Marshall, recorded at the beginning of November. As David Klinghoffer noted yesterday, the subject of the debate was Meyer’s book Darwin’s Doubt. Yes, that’s the same Charles Marshall who reviewed Darwin’s Doubt in Science back in September. See here for our multiple responses.

It was an excellent debate, with both participants offering important insights and good arguments, though in my opinion Meyer unquestionably had the better of it, especially concerning the key scientific question of the origin of the information necessary to build the Cambrian animals. Nevertheless, both parties came to the table ready to engage in serious, thoughtful, and civil discussion about the core issues raised in Darwin’s Doubt, and we commend Marshall not only for participating, but for focusing his critique of the book on the central scientific issues, something other critics have conspicuously failed to do.

The debate was consequently both constructive and civil. Both parties complimented, as well as critiqued, the work of the other. Marshall, for example, described the first third of Darwin’s Doubt — the section that discusses the Cambrian and Precambrian fossil record, Marshall’s own area of principle expertise — as “good scholarship.” He also said it “looks like good science” and that Meyer “writes well,” and that he (Marshall) “really enjoyed reading”Darwin’s Doubt. Meyer, for his, part expressed his admiration for Marshall’s many scientific papers in paleontology and noted that he had been looking forward to the conversation because he and Marshall clearly “shared a passion for the same subject,” despite their different perspectives. Of course, Marshall is not pro-ID and both men expressed spirited disagreements, but they did so in a mostly respectful way that made the debate all the more interesting and engaging to listen to.

I was very impressed with Dr. Marshall’s performance during the debate, although he did try to poison the well a bit against ID at the beginning, and he got nasty at the end. It’s amazing how Dr. Meyer was able to get him to stop it with the politics and get serious, just by sticking to the science. Even when Marshall got insulting at the end, it was still valuable to see how the other side has to abandon rational argument and scientific evidence once they see that they can’t win on the merits. It’s “Inherit the Wind” in reverse.

Evolution News also posted a more complete guide to the debate in this post, and I recommend that you read that post before listening to the debate if you are not familiar with the science.

This is a great debate, and you definitely ought to listen to it. I hope I’ve posted enough here to convince you. If you haven’t yet bought “Signature in the Cell” and “Darwin’s Doubt“, then I urge you to get them, although they are intermediate/advanced level books. The two books are the state of the art in intelligent design research, good enough to be debated with a University of California, Berkeley professor of biology. Dr. Meyer is the real deal, and if you want to be convincing on these important scientific issues, you need to learn the scientific evidence from his books.

If you are not a regular reader of the Evolution News blog, you really should be. It’s also a good idea to subscribe to the Intelligent Design: The Future podcast.