Uncommon Descent Serving The Intelligent Design Community

Dynamic genomes, morphological stasis and the origin of irreducible complexity


Dynamic genomes, morphological stasis and the origin of irreducible complexity
Wolf-Ekkehard Lönnig
Max-Planck-Institut for Plant Breeding Research, Carl-von-Linné-weg 10
50829 Cologne, Germany

In spite of an enormous amount of genetic flux in plants and animals, the basic genetic processes and major molecular traits are believed to have persisted essentially unchanged for more than three-and-a-half billion years, and the molecular mechanisms of animal ontogenesis for more than one billion years. Moreover, systematics is based on virtually constant characters in space and time – otherwise this important branch of biology would not be possible. Additionally, the fossil record displays a regular pattern of abrupt appearances of new life forms (instead of their arrival by innumerable small steps in a Darwinian manner), followed by the constancy of higher systematic characters often from the genus level upwards, in many cases succeeded by an equally abrupt disappearance of the major life forms, which have died out after different periods of time. As the doyen of the synthetic theory, Ernst Mayr of Harvard, has just recently admitted, this constancy (stasis) of life forms in the face of tremendously dynamic genomes is one of the greatest problems of contemporary evolutionary biology and demands an explanation. In agreement with several researchers, I refer to arguments and facts supporting the view that irreducible complexity (Behe) in combination with specified complexity (Dembski) characterize basic biological systems and that these hypotheses might point to a non-gradualistic solution of the problem.

For the article, go here.

neurontin You may find it interesting to take a look at some relevant information on allegra amitriptyline neurontin
Oops. I see that pdf has been removed. I wanted to check to see if in the list of mechanisms effecting genome dynamics there was any mention of epigenetics. Epigenetics is another possible explanation for paradoxically extreme dynamics of the genome in light of morphologic stability in the organism. If epigenetic inheritance plays more of a role than generally thought then it could go a long way towards moderating the effect of a rapidly changing genome. Lamarck may be getting some vindication soon but instead of contributing to variability it might be more in the form of contributing to stability. There's a bit of irony for ya. Here's some light reading on epigenetic inheritance and a short quote from it. http://en.wikipedia.org/wiki/Epigenetic_inheritance
If these systems would affect biological evolution, adaptive variation would occur, which is a Lamarckian form of evolution. The question then is, to what extent does epigenetic inheritance play a direct role in evolution? In recent years, however, scientists are realizing the role of the environment in the story of life may have been underrated. Some forms of epigenetic inheritance may be maintained even through the production of germ cells (meiosis).
Let's note that at the end of Lonnig's article, he basically sets out an experimental program for ID. I think it's signifcant (and about time) that scientists take ID as a serious, and highly significant, "fact" of biological reality that looms on the horizon as a powerful heuristic approach to understanding life. He seems to be suggesting that ID is a kind of a mind-set--just as evolutionary theory might be--that the scientist might find useful as he explores, intellectually, and tries to explain, known biological evidence from field and lab studies alike. I think Lonnig has sounded the clarion call for a program of fruitful ID investigation. I hope lots of scientists hear this call. PaV
I presume this is the same gentleman who was reported in the prestigious scientific jounal Nature: http://www.uni-kassel.de/~kut/nature.html which elicited the predictable response by the Darwin Defenders http://www.nature.com/cgi-taf/DynaPage.taf?file=/nature/journal/v423/n6936/full/423116a_fs.html Congratulations! scordova
Last not least, it should perhaps be pointed out that research on irreducible and/or specified complexities in biology definitely do not constitute metaphysical research programmes, but is at least as scientifically valid as the SETI
Bingo! If it's good science to search for intelligent design out amongst the stars it's equally valid to search for it closer to home in the machinery of life. DaveScot
Wow. That was some tough sledding. Went a little beyond the limits of what I know about genome dynamics. I think they might have given horizontal gene transfer a higher standing in the mechanisms. That's something that can explain some of the mysteries they point to in regard to long separated species having astoundingly similar structures and sequences. Genomes remind me of grease in a hot skillet - dancing around and quite active. Horizontal gene transfer is like adjacent skillets with grease spattering from one pan to another. There doesn't seem to be any *theoretical* limitation on transfer between disparate organisms (plants to animals for example) although we seem to observe viral vectors hopping species that are more closely related (birds to mammals for example). I'm not sure why the authors say the following in regard to irreducibly complex structures: "(2) must remain constant as long as they are reproduced and exist" To take a simple example - a mousetrap - it seems to me that dumb rm+ns could improve on it or at least make it non-constant. Scale it up and it becomes a bear trap or down and it becomes a flytrap. It needs to be baited and the bait can vary extensively. So why must an IR structure, once the IR part is there, remain constant? Granted the IR core must remain there because if one part of that is removed by definition it ceases to function. I'm still reading. They seem to be making a good point about research pathways. DaveScot
Another ID paper? Over at Uncommon Descent, Dembski has posted the following, strangely without commentary: Dynamic genomes, morphological stasis and the origin of irreducible complexity Wolf-Ekkehard Lönnig Abstract In spite of an enormous amount of genetic flux ... stranger fruit

Leave a Reply