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Wednesday, March 30, 2011

Questions on How We Got Here

Below is a portion of an essay that sets out, in language understandable by lay persons, the disagreements so many present-day scientists are having with the concepts now known as neo-Darwinism. Many of us who have considered some of the implications of modern-day discoveries in microbiology and archeology are just baffled that the science establishment continues to resist these implications. As of now, more than 800 scientists, all PhD’s or MD’s, have signed a pledge that they dissent from Darwinism.

Mutations

by MATT CHAIT NOVEMBER 5, 2009 BEYOND EVOLUTION (EXCERPTS)

“In this post I question some of the assumptions of both Darwinian evolutionists and intelligent designers. Intelligent designers are not to be confused with creationists. Creationists are people that refuse to consider any ideas or conjectures, no matter how they were arrived at, that are in conflict with the account of creation as found in the biblical Book of Genesis. Intelligent designers are people, often scientists, who reject Darwinian evolution as an explanation for the origin and development of life because they feel that it fails, as a theory, to explain the bewildering complexity and coherence of life forms.

Perhaps the population of creationists is dwindling as more progress is made in biological research, but with the use of modern instrumentation, including electron microscopes, X-ray crystallography and DNA micro arrays, and the fantastic complexity of life that is revealed at it's most minute and 'simple' level, the ranks of intelligent designers, as opposed to creationists, are swelling.

Just as people tend to confuse and conflate creationists with intelligent designers, there is much confusion and conflation regarding the theory of Darwinian evolution itself. There are really, as microbiologist Michael Behe, the 'father' of intelligent design explains, three separate yet related Darwinian notions. The first is the theory of common descent which states that all life forms have evolved from the same original ancestor. There is seemingly a lot of proof for this part of the theory, including many similarities of structures and function in all life at the molecular level and within phyla or kingdoms or species, a remarkable similarity of structure and function at the level of visible organs and traits.

From the perspective of modern science, including intelligent designers, this is powerful evidence for a common ancestor. And it does seem like a fairly reasonable assumption: if we have hair and an ape has hair and a raccoon has hair; then at some point in the very distant past, there was probably an ancestor of all three of ours that had hair. As I say, intelligent designers have no quarrel with this aspect of evolutionary theory, although I do, and will discuss this later on.

A second notion of evolutionary theory is natural selection, which is basically this: If there are a variety of species and a variety of different individuals within a species, then those species and those individuals that are more fit, that are better adapted to their environment, will survive more readily than those individuals and species that are not as well adapted. Over time the better adapted individuals will replace the more poorly adapted ones and will dominate that species, just as the better adapted species will dominate other species.

Natural selection, for the most part, is also not really argued among intelligent designers. It is obviously true, but perhaps, more complicated than originally thought. The qualities that make an individual member of a species better adapted are often other than the obvious qualities of stronger and faster. Sometimes species and individual members of species survive because they are better able to float below the radar of predators. Sometimes they are better able to cooperate among themselves to get their needs met, and function better in groups. And so on. Also, as the environment keeps changing, it favors certain individuals over others and certain species over others. As the weather gets hotter then colder, then hotter, different species and different individuals within species are favored. The same is true for cyclical changes in humid vs. dry environments, warmer vs. colder ocean water, and many chemical changes; more saline vs. less, more oxygenated vs. less, more carbonized vs. less, etc. Once the basic conditions on this planet stabilized and the atmosphere became oxygenated, all indications are that environmental changes have been cyclical rather than linear. It's hard to imagine a linear evolutionary path being naturally selected by cyclical changes in the environment.

It should be noted that both of these first two aspects of evolutionary theory, common descent and natural selection, have no power what so ever to explain how anything originally got here or how anything gets more complicated once it is here. The first part alludes to a common ancestor, but from where and how did this ancestor arrive? The second deals with selection not creation. Natural selection can cull from existing types, but how do those types find their existence in the first place?...”

“The only explanation for the creation of new species, new forms, new body plans and for the increase in complexity of these forms and plans in Darwinian evolution is through the avenue of blind, accidental and fortuitous mutations. Although Darwin had no way of knowing it in his day, these mutations take place, according to modern science, by an accident in the genetic copying of genes during the process of replication.

Genetic sequences are long strings of nucleic acid molecules, or nucleotides, which are coded for specific amino acids. In our cells, a long series of coded nucleic acids is transcribed within the nucleus onto an RNA molecule which transports this code outside of the nucleus of the cell to a ribosome where it is translated to a corresponding long series of amino acids that, when linked together and folded, form a protein.

A genetic copying accident can result in a change in a nucleic acid, which can result in a change in the amino acid that that nucleic acid is coded for. These accidental changes are very rare (about one 'mistake' in one hundred million copies) and are almost always either deleterious, and damage the mechanisms of the cell and the workings of the body; or neutral and have no visible effect at the level of either the cell or the organism; still, extremely rarely, there is a very, very rare mutation that, according to the theory, causes an improvement in the workings of the cell, that increases the survivability of the cell and the organism of which this cell is a part; and future generations will favor this positive change and in this way the organism will improve and eventually, over a very, very long time, undergo radical change.

This part, the random mutation part, is the one that most bothers intelligent designers. It just does not seem, to intelligent designers, to be a process that occurs frequently enough to deliver anything like the amazing variety and complexity of life forms that we find today. So the math does not work. Also you would expect from this sort of change a very gradual yet very consistent change among organisms so that not only would every organism be linked in very gradual clear steps to every other organism, but that these changes should have taken place at consistent, regular and frequent intervals in our history.

Yet, simple observation tells us that there are no such links. Each mammal is very much a mammal and not to be confused with a bird or an insect; just as every insect is very much an insect and not to be confused with a reptile or a fish. Not just on the outside of their bodies, but each has a completely distinctive internal form of organization; there is clearly a mammalian way of organizing internal organs, a mammalian kind of digestive, reproductive and nervous system, and there are very clear and distinct avian and insectivore forms of internal organization.

Also, historically, there is absolutely no evidence of this gradual, relentless change of species. In fact, quite the opposite is the case. All evidence points to the first cells appearing suddenly, about four billion years ago, at the moment that conditions on this planet supported their survival (when the surface of the Earth became cool enough to have non-boiling water). There are no traces of organic tide pools (the so-called pre-biotic soup), no traces of any organic material at all prior to the appearance of these photosynthetic, metabolizing, digesting, growing and environment sensing bacteria.

Then, for two billion years after that, fully half of the entire history of life on Earth, there was absolutely no evolutionary change, in the sense of life forms changing their basic structure or complexity. Four billion years ago there were bacteria and only bacteria; and two billion years later there were bacteria and only bacteria. Now among these bacteria there were all sorts of adaptations, so that bacteria were able to thrive in all kinds of environmental conditions: extreme heat, extreme cold, high acid, high base, little water, etc.

If by evolution one means adaptation, then, yes evolution was taking place. But what we commonly think of as evolution is the evolving of one species from another; of a change of shape, body plan and basic structure. In that sense of evolutionary change, for two billion years there was none.” Beyond Evolution

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1 Comments:

At 9:26 AM, Anonymous Anonymous said...

Maybe our head intelligent designer created the bacteria and said - let's just see how things evolve from here. Then, 2 billion years later checked up on things and said - well, that didn't work so well, maybe I need to stir things up a bit.

As far as creationists, I don't see their relevance to this. They need to accept the fact that their timeline is off substantially, then we can move forward from there.

I believe in intelligent design and the additional impact of evolution to tweak existing designs and to come up with larger variations. I see no conflict in both working together, but I don't see evolution explaining all of today's variety.

Steve

 

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