Posted on 05/01/2006 8:29:14 AM PDT by SirLinksalot
The Cambrian explosion has previously been thought to be the time of origin of multiple body plans and metazoan life. It used to be thought that the Mediacaran lifeforms were a sister clade. However, now several types of Precambrian organisms are thought to be ancestral to later forms, and we have fossils of metazoan embryos going back into the Precambrian.
"However, there is a growing body of evidence that many so-called vendobionts may actually belong to established metazoan phyla, although debates about the proper assignment of individual taxa continue. At the very least, we consider that there are strong arguments against the application of the vendobiont hypothesis to all the Ediacaran taxa (Gehling, 1991). The Cnidaria is almost certainly represented in the Precambrian (Conway Morris, 1993b). Amongst Ediacaran genera Spriggina has been interpreted as an annelid (Jenkins, 1992), Arkarua as an echinoderm (Gehling, 1987), and Parvancorina (considered again below) and Praecambridium (Jenkins, 1992) as arthropods. Other taxa have attracted more diverse speculation, Dickinsonia being variously interpreted as cnidarian, flatworm or annelid (see discussion in Valentine, 1992)."
Fortey, R. A.; Briggs, D. E. G.; Wills, M. A. "The Cambrian evolutionary ‘explosion’: decoupling cladogenesis from morphological disparity." Biological Journal of the Linnean Society (1996), 57: 13–33.
This is not saying that there was no Cambrian explosion, just that some major groups appeared earlier than that. The Cambrian explosion definitely was a dramatic event.
This next article I'd really encourage you to find, copy or print out, and read five times! I wish I could post the whole thing.
"Extant monophyletic groupings are always morphologically distinct from their extant sister-group, and that distinctness is brought about by subsequent extinction of the lineages (plus its offshoots) that led to each of them, away from their last common ancestor. As random extinctions through time slowly remove lineages, the most basal taxon of a clade will sometimes be the victim, thus widening the path-length between the surviving most basal members of extant sister clades (Fig. 3). The bases of clades are therefore eroded by extinction, and, as only living members of the clade can rediversify, this is a permanent loss. These extinct basal taxa will not possess all of the apomorphies that define the basal node of the surviving clade. It should be noted that this process will occur whether or not basal members of clades are particularly prone to extinction or not; there does not have to be anything ‘‘special’’ about basal taxa. One further aspect about these now extinct basal taxa is that they would have accumulated their own autapomorphies not possessed by the extant taxa. As a result, these basal fossil taxa are bound to differ from the extant clades: they will not be diagnosable as members of those clades; and they will show a confusing mixture of some but not all features of those clades, together with a set of features absent from them. It should be noted that this characteristic mix has been repeatedly noted in Cambrian fossils. For example, Hughes (1975) said of the Cambrian arthropod Burgessia: ‘‘what is apparent from this restudy is that Burgessia did possess a mixture of characters . . . many of which are to be found in modern arthropods of various groups’’ (Hughes, 1975, p. 434). . . .
"One example of the sorts of possibilities that stemgroup reconstruction offers is provided by the arthropods (e.g., Budd, 1998, 2001b). Optimization of the terminal character states of the various stem-group demonstrates the most parsimonious reconstruction of the evolutionary stages passed through by ancestral arthropods. A remarkably complete series is now available, demonstrating how the most basal, worm-like taxa of the entire Arthropoda sequentially acquired the important features characteristic of their clade, including the sclerites and lever-style musculature (Budd, 2001b), components of the biramous limb (Budd, 1996), and even how the complexities of the arthropod head were assembled (Budd, 2002), a construction that can be corroborated by the recent fauna (Eriksson et al., 2003)."
Budd, G. E. "The Cambrian Fossil Record and the Origin of the Phyla." Integrative and Comparative Biology, 43:157–165 (2003).
As I said before, we do have some deposits with excellent soft-bodied fossils, but these are the exception rather than the rule. As js1138 pointed out, we can tell that soft-bodied creatures (and creatures with other characteristics and from other environments) are under-represented in the fossil record by examination of fossils of living species and genera. Typical fossilization conditions preclude the preservation of details of soft flesh. Heck, we don't even need to check and see which modern organisms are missing or underrepresented in the fossil record, just look at the fossils that are available of hard-shelled and bony remnants. Trace fossilization of soft flesh around an organisms bones or lining its shell are extremely rare.
"TToE is supported by evidence"
Yawn. . .
"It doesn't require abiogeensis"
Duh. I know that. I never mentioned [sic] 'abiogeensis'.
"nor does it require observation (although we do have direct observation of micro-evolution)."
Yeah, that's the whole point. No one argues about what we have direct observation of.
I got 'em all OVER my yard!
(Ain't GOT no hair!)
Mention backing up again and you'll lose dinner!
`Twas brillig, and the slithy toves
Did gyre and gimble in the wabe:
All mimsy were the borogoves,
And the mome raths outgrabe...
But it still leaves one as master of his own domain.
"Beware the Jabberwock, my son!
The jaws that bite, the claws that catch!
Beware the Jubjub bird, and shun
The frumious Bandersnatch!"
I love Lewis Carroll :)
That was quite a non-post. Pretty standard in the CRIDer arsenal. But "No one argues about what we have direct observation of" is pretty funny. There are a LOT of scientific debates on gravity, string theory, DNA, etc. etc. etc.
You need to get out more and see what really happens in the world.
You are, of course, correct. We so-called "Evos" want to keep that separation in place. Somehow, CRIDers have the feeling that by debunking TToE (which is impossible given facts available to date), they somehow buttress Creationism (which is Faith-based) and make this wierd linkage that somehow understanding TToE makes one an athiest. And not just an athiest, but a God-hating, anti-Jesus athiest.
So we man the threads to keep disinformation and ignorance from creeping into our already-screwed up schools.
It is a thankless task but one we take on for future generations.
The authority of God is sui generis, and quite beyond human understanding. God is "beyond" spacetime reality and all categories of human thought. He is not subject to the order of creation which He created. There are some who say (as you do) that God is "vengeful," "inflicting infinite consequences" on human miscreants. To me that is a caricature; for God is Love, Truth, the Good, Justice -- at least these are the descriptors that a faithful Christian who responds to His call of love and grace attaches to Him. Perhaps your understanding of the JudeoChristian tradition is a tad superficial, King? Have you ever really bothered to "study" it? Or ever allowed yourself to be drawn by God's love for you?
In short, I think some of your assumptions may not be too well founded. Which maybe is why we're having such a difficult time understanding each other. For one thing, I don't know what in the world you want me to "try again." Please be more specific, King!
Thanks for writing!
Well said, hosepipe. Your insight about Iraq seems quite on the money to me. Thank you so much for writing!
I hope you don't mind me jumping in on your conversation, but I wanted to comment on the above.
I concur with your assertion that God isn't vengeful, but probably for much different reasons. One of those reasons is that I disagree that God is not subject to order, and I also disagree that God is beyond space-time. My personal feeling is that God is subject to order because God IS order, and God is not beyond space-time, but rather underlies it. I sometimes think that both religious philosophers seeking to determine the nature of God and scientists seeking a "Theory of Everything" are stumbling towards the same goals. I believe that the reason things work the way they do is because we have a fundamental order to the universe, perhaps someday identifiable as God.
I think I came to this conclusion after a summer intensive course in Dante. I was reading Sagan's "Contact" concurrently with studying the Divine Comedy. We were discussing the means by which souls arrive in hell, according to Dante, and had come to the conclusion that the Inferno suggests not vengeance, but a certain degree of determinism. That is, similar perhaps to binary code, if you are at 0 when you die, you go to heaven, or if you are at 1, you go to hell. Your own actions determine your setting. Of course, it's more complicated than that, but that's the gist.
Between that and Sagan's idea that messages have been embedded in numbers like Pi got me thinking that maybe the numbers aren't the signifier, but the actual signified. The reason that things like evolution of species (to segue briefly back to the topic of this thread) work so beautifully is due to the fundamental order of things that holds the universe together. An order that I do not believe was created by God, but that actually is God.
Anyway, that's my two cents.
Further cross-check assumptions such as the constant rate of atomic decay and constant lightspeed by observing atomic decay rates in distant supernovae.
Thank you very much for your post #1276...you have quite concisely, approached God in a manner that was lovely...it will take me some time to let it sink in, but I do believe what you have stated, is something I could well embrace...
It may be just your two cents worth, as you say, but heck, I think those thoughts are worth a million bucks...
Thanks :)
Such a thing is an impossibility.
That the impossible does not occur, is neither an argument for evolution, nor an argument against anything else.
Sexual reproduction, in and of itself, does not infer evolution, and to suggest that it does is simply absurd...like it or not.
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