Badger3k
Posts: 861 Joined: Mar. 2008
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Quote (Zachriel @ Sep. 11 2008,10:00) | Wow. And Sheldon is a physicist. But let's start with his understanding of orthodox evolutionary theory.
Quote | Sheldon & Hoover: Now when Darwin suggested that random mutations combined with natural selection would provide a chaotic explanation for apparent design and order in biology, he was making a mathematical statement about longrange correlations |
Darwin didn't "suggest" random mutation. This is a much later development. Darwin suggested the source of variation was non-random and Larmarckian.
Quote | Sheldon & Hoover: That is, the appearance of progress is driven by random, local processes, much as frost flowers form on a window, without any information beyond a local, undirected interaction (e.g., diffusion-limited growth). |
The "appearance of progress" is not thought to be random, but highly non-random due to natural selection. For instance, many terrestrial plants grow towards the sky. There's a reason for that.
Quote | Sheldon & Hoover: Neo-Darwinists argue that the order, which is visible in living things, is much like that of a crystal, a long-range spatial order slowly, and randomly, accumulated over time. |
No. Accumulation is not random. Adaptation occurs when variations are *selected* by environmental conditions.
Quote | Sheldon & Hoover: if we ignore long-range order, and plug in a simple mathematical model of evolution as the accumulation of random mutation steps, the diffusion of information (or progress) has no "arrow of time", no "progress rectifer", no "success ratchet" that accepts only progress and rejects regress. |
If organisms compete with one another, they can create a ratchet-effect—without any long-range ordering. This is called the Red Queen Effect, "It takes all the running you can do, to keep in the same place."
Quote | Sheldon & Hoover: That is, rather than finding many organisms spanning the reptilian to amphibian transition, or the mammalian to marsupial transition, we find non-Gaussian distributed clusters of species. |
This is sort of a zeroth-order approximation. It's as if Sheldon thinks life evolves randomly on a perfectly flat environmental landscape. The environment is not only highly non-random and changing, but includes other organisms.
Darwin discusses one mechanism of clustering and divergence in Origin of Species. If two closely related species are in competition, either one will be forced to extinction, or they will tend to diverge. The Red Queen Effect is another.
Quote | Sheldon & Hoover: That is, with lifecycles shorter than a bacteria, with a multiplication factor of 200, with replication errors much higher than a bacterium, natural selection should be brutal and swift for these phages, making them ruthlessly effient. Yet despite this evolutionary pressure, phages have enormous DNA variation, even containing DNA that has no useful purpose to the virus {44}. |
Reading the cite, the authors suggest that these genes *do* have a function for the virus saying, " Are these genes that have been accidentally acquired from the host and confer no fitness benefit on the phage, or do they indicate important features of how the phage interacts with its host? ... during infection a common phage strategy is to switch off host gene expression, which could impair photosynthesis and thereby deplete the energy required for viral replication. The provision of a viral D1 protein would permit the repair cycle to continue until the cell lysed to release the phage progeny."
Quote | Sheldon & Hoover: Therefore the thesis of this paper, is that the punctuated equilibria observed by Eldredge is not due to some long-range modulation of the point-mutation rate caused by geographically isolated communities, but rather by the sporadic transport of new genes through cometary transport. |
Okay, so now we know what they're getting at. It would be easier to take their speculations seriously if they at least expressed some basic understanding of orthodox evolutionary theory. |
Wait a minute - species do not change due to natural processes, but because they are infected from space? Seriously? ???
-------------- "Just think if every species had a different genetic code We would have to eat other humans to survive.." : Joe G
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