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To: Stultis
Consider the evolution of the modern horse from eohippus

So. There's not enough sediment available to preserve any transitional form between the various horse species, but enough sediment to preserve actual examples of each species in the evolution chain?

What a staggering coincidence! We have sediment preserved long enough to show an actual example of each species in the chain, but all the sediment that might have preserved transitional forms was subsumed into the magma.

172 posted on 01/18/2005 12:27:03 PM PST by frgoff
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To: frgoff
So. There's not enough sediment available to preserve any transitional form between the various horse species, but enough sediment to preserve actual examples of each species in the evolution chain?

Actually, we don't (and in nearly all cases can't) know that. The example of living species has taught time and again that the kind of purely morphological identification of species that is necessary and unavoidable with fossils is often misleading. When living species are actually studied it turns out that virtually (or even exactly) identical morphotypes sometimes belong to distinct and separate species, whereas in other cases one species might include forms that are morphologically very different.

Even assuming a dependable correspondence between morphological and biological species (as there indeed is at some general level, albeit with exceptions) you still have the problem of natural variation within species. Now some species are more variable and some are less so, but even if the degree of variation was approximately constant from one species to the next, you still need to understand the parameters -- which characters vary, what the extremes are, ans so forth -- in order to dependably identify species morphologically.

Even then it's possible that two perfectly good and distinct biological species might resemble each other sufficiently that the ranges of variation overlap between the two. In this case you couldn't tell which species an individual belonged to just by looking at it. You'd have to observe the population the individual belonged to.

Now apply all these considerations (that we KNOW are commonly true of species by observing living ones) to the case of fossil species. It quickly becomes clear that we might be looking at a form that is exactly transitional between two species, but would have no possible way of knowing or showing that.

When we only have a few dozen, or even a few hundred, examples of a morphological type that is inadequate to dependably assess the full range of variation that would be present in any typical species, let alone within a genus that might contain any number of similar species. We have little or no way of really knowing (expect by some statistical approximation) whether the fossils we group under the name Hyracotherium represent the natural variation of one species, or of several closely allied ones.

IOW, when you demand that we produce transitional between species, I don't think you understand that you are making a demand that can't be fulfilled (except possibly in a few very unusual cases) in the nature of the matter, even if evolution is true.

Besides, it's kind of an odd demand. Many creationists in the 19th century and before held to a fixed species view, but few, if any, modern ones do. In fact creationists typically get offended when people assume they believe in absolutely fixed species. Why wouldn't a creationist also expect transitionals at the lower species level?

What a staggering coincidence! We have sediment preserved long enough to show an actual example of each species in the chain, but all the sediment that might have preserved transitional forms was subsumed into the magma.

Oh, come now. Sonleitner never suggests we have "each species in the chain". In fact I don't doubt for a minute that any paleontologist would presume that any number of species are missing. We have what we have. A few scraps of time preserved here that there. Even within those scraps it's, as a mere statistical phenomena, the most widespread (geographically) and long-lived species that will tend to leave a few fossils that happen to be noticed by a paleontologist or fossil collector before they erode away.

I feel a little silly even responding to such a silly strawman argument (if you can even call it an argument) because it's so obvious on the face of it that we can't possibly have "every species in the chain". Consider that there are only (last I knew) about a quarter million or so species that have been identified from fossils. Measure this against the number of species living on the earth right now (representing just one "slice" of time). There are a few millions to a few tens of millions of living species (very few represented by fossils, btw).

284 posted on 01/18/2005 6:04:41 PM PST by Stultis
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To: frgoff
What a staggering coincidence! We have sediment preserved long enough to show an actual example of each species in the chain, but all the sediment that might have preserved transitional forms was subsumed into the magma. I think you missed the point of the original quote. That being, the earth has not cooperated with science in preserving each transitional step by having the correct conditions present at the time. (Aww, poor scientists!!) But, due to this, any "transitional" form which we have found preserved, becomes by definition a known species - with missing transitional forms before/after. There is probably much validity in the assumptions made by science reagarding the "mutation" between one species and another (along a common path!!) - i.e. since we have fossil records of early man - "middle" man and the present, there are some conclusions we can draw regarding the "missing" ancestors. I think this is equally true for other species as well (reptiles for example). I do have a harder time grasping the "apes to man" steps. There seem to be some commonality between us, but the "missing link" (like the Holy Grail) appears to be more a matter of faith than one of, what an earlier poster refered to as, "scientific fact" (and I use it in the way he meant it). I admit that I do not follow the current news of evolution closely, so if my assertion is false, I invite correction - but, it seems that the only "missing link" the evolutionists are seeking is the one which explains man. No other species needs this (as I said - this may be entirely false!!).
548 posted on 01/21/2005 2:41:57 AM PST by An.American.Expatriate ((This space for let))
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