Unlocking the Mystery of Life

The question of the evolution of eukaryotic cells from prokaryotic ones has long been a topic of heated discussion in the scientific literature. It is generally thought that eukaryotes arose by some prokaryotic cells being engulfed and assimilated by other prokaryotic cells. Called endosymbiotic theory, there is some empirical basis for this. For example, mitochondria contain a single circular genome, carry out transcription and translation within its compartment, use bacteria-like enzymes/components, and replicate independently of host cell division and in a manner akin to bacterial binary fission.

Despite such evidence, however, when assessing the causal sufficiency of unguided processes, they — predictably — come up short. After all, it is all-too-easy to lapse into a long-discredited Lamarckian “inheritance-of-acquired-characteristics” mentality. It is important to bear in mind that, even if a cooperative assemblage of prokaryotes did by some fluke of luck arise, such an arrangement is of no evolutionary significance unless there is a genetic basis to ensure its propagation.

A second problem with this scenario is that mitochondria use a slight variation on the conventional genetic code (for example, the codon UGA is a stop codon in the conventional code, but encodes for Tryptophan in mitochondria). This implicates that the genes of the ingested prokaryotes would need to have been recoded on their way to the nucleus. The situation becomes even worse when one considers that, in eukaryotic cells, a mitochondrial protein is coded with an extra length of polypeptide which acts as a “tag” to ensure that the relevant protein is recognised as being mitochondrial and dispatched accordingly. The significant number of specific co-ordinated modifications which would be required to facilitate such a transition, therefore, arguably make it exhibitive of irreducible complexity.

Scientific American recently reported on what has transpired since the completion of the Human Genome Project ten years ago. When the HGP was first announced in 2000, many scientists said that it would be the key to understanding disease and for developing cures. Ten years later, however, this has not been the case. The human genome project has aided in developing better research and technology, particularly in our abilities to sequence genes. It has also shown us that much of what we once considered junk DNA isn’t really junk at all. (See here, here, here, and here for past ENV discussions on junk DNA). However, scientists are coming to a sobering conclusion that perhaps their models and assumptions on the nature of disease may be mistaken.

It is difficult to escape the use of technological language in discussing cellular functions. Stephen Meyer has a section on information theory in Signature in the Cell and basically uses technological language or metaphors to describe DNA. The best language for describing DNA uses analogies to writing, copying and pasting, and software. Another example of this is in Behe’s book, Darwin’s Black Box, where he uses a rotary motor to describe the function of a bacterial flagellum. This brings to mind an interesting question: what is the relationship between the development of technology and the discovery of the inner workings of the cell? They seem to go hand-in-hand.

This interview with Dr. Stephen Meyer about his book Signature in the Cell was conducted some time ago, but is a very good introductory discussion of DNA manipulation, cellular engineering and attempts to create living cells with computer assembled DNA at its heart. Display content from www.discovery.org Click here to display content from www.discovery.org. Please enable JavaScript in your browser to load this content. Always display content from www.discovery.org Open content directly

[NOTE: Today we welcome a new contributing writer to Evolution News & Views, Guy Coe. Mr. Coe graduated from the University of California at Davis with a B.A. in Rhetoric and a minor in political science. As a lifelong student of argumentation and logical analysis, his career has taken him from Executive Salesman, to News Reporter, to U.S. Senate Communications Aide, to Tour Guide, to Retail Management, to father of a budding teenager, “where all communications logic begins to break down.” With a lifelong interest in the issues of intelligent design and origins theories, his status as “interested layperson” allows him to continue to follow the evidence where it leads, while showing proper respect for the lifelong dedication displayed by practitioners of the hard sciences. And, somehow, he still manages to communicate with his teenager…]

Much ink has been spilled, and heat generated, over the “intrusion” of the intelligent design hypothesis into the now seemingly exhausted “creation vs. evolution” debate.

Is intelligent design only reworked creationism, or is it something dynamically different? Now that intelligent design has “evolved” a little, and the theory of evolution has been a little more “intelligently designed,” the focus of our attention has been changed back to the very puzzling questions of the origins of the complexity within cellular organization, while the “old regime” merely argues over the vestiges of an assumed progression from this unexplained point.

For their parts, many creationists and evolutionists are at such an impasse in old paradigms that each of them are left shaking their heads in wonder at the apparently willful ignorance of their opponents — building their knowledge base on two supposedly vastly different approaches, and being at a loss to explain how the “convincing” evidence each position marshals can be so blithely dismissed by the “other side” — to the point that charges of irrationality, and even willful self-deception, are rife.

As an eager observer of this unfolding drama over the last several decades, I have to say that my honest impression is that both sides manage to play fast and loose with the facts, ignore the anomalies, and distort the evidence, by virtue of prior philosophical convictions. Or perhaps it is more charitable to say that, given the same set of facts, many come to vastly different interpretations by virtue of poorly-constructed logic, selective evidence, and poor methodology.

It’s been long known that the bacterial flagellum can spin in one direction and then quickly reverse directions and spin in the other. A recent issue of Nature has an article titled, “Structure of the torque ring of the flagellar motor and the molecular basis for rotational switching” which elucidates some of the biomechanical properties of the FliG motor protein that allows this rotation switch to occur: The flagellar motor drives the rotation of flagellar filaments at hundreds of revolutions per second, efficiently propelling bacteria through viscous media. The motor uses the potential energy from an electrochemical gradient of cations across the cytoplasmic membrane to generate torque. A rapid switch from anticlockwise to clockwise rotation determines whether a bacterium runs Read More ›

In this new video, Dr. Stephen Meyer explains the historical scientific method and how it applies to the origin of the information that makes life possible. It’s the question facing origin of life researchers: where does the information come from? http://www.youtube.com/v/XexHxgxTbWY

According to a live-blogger at the Southwestern premiere of “Darwin’s Dilemma” earlier tonight, a Darwinist during Q and A challenged Stephen Meyer and Jonathan Wells by charging that the interviews in the film of noted paleontologists Simon Conway Morris and James Valentine (both evolutionists) were done a decade ago. “Are you aware that the interviews of Morris and Valentine were done 9 and 10 years ago?” the questioner asked. Apparently the implication was that the interviews were so old they no longer accurately reflected the views of Morris and Valentine. Except that the questioner was flat wrong. According to Illustra Media, with whom I checked tonight, the interviews were done specifically for this project in October and November of 2006 Read More ›