We've crossed swords over this matter before - but on another list. I
write on this occasion as a result of some recent correspondence with
Paul in which I cited the alleged transition as one which stretches the
imagination to breaking point. He responded by suggesting I looked at
the list of evidences that you had compiled at
http://www.isource.net/~grmorton/transit.htm
Having now done that, I am wondering whether you would mind clarifying
some of the matters raised, viz
(1) I am a little surprised that the 'timetable' you give fits the
sequence of alleged transitionals so well. Can you confirm that these
temporal data in respect of the sites of discovery - some of which were
widely spread (eg Pennsylvania, Scotland, and Russia) - really preceded
the claimed discoveries? I have to confess, I had no idea that
geological dating in sedimentary deposits was so exact a science these
days! Can you perhaps briefly explain the method(s) used.
(2) Assuming the reported details to be true, how would you respond to
the suggestion that the fossil remains might equally well be interpreted
as relating to created kinds, now extinct?
Sincerely, and with kind regards,
Vernon<<<<<<
First off, my apologies for not being able at this moment to profer the
usual abundant documentation. I am in the midst of a move and my papers etc
are not available. I also had my computer stolen with many of my research
notes. My back ups have not been completely restored. Secondly, there are
error bars on each of the dates on my page that I did not report. What was
reported was the most probable age.
Most of the dating of these stratum is based upon two items: biostratigraphy
with input from radiometric dating. The biostratigraphy largely consists of
extinct animal species which are found in a predicatable order around the
world. These consist of marine graptolites, trilobites, conodonts etc.
Each index species is a unique shape and is found in a unique worldwide
order and are found only in a few layers. When these layers overlie a layer
to be dated, say conodont A lies over a sandstone where a given fossil is
found, we know that the fossil is older than the index conodont A. If we can
radiometrically date a layer with conodont A then we can date the
fossil-bearing strata as no younger than that date.
Now, creationists have long complained about index fossils being circular.
They are not.
If I have the following order of conodonts--world wide then the layering of
the geologic strata acts as a relative age marker.
conodont X
conodont w
conodont T
conodont s
conodont r
conodont m
conodont n
conodont g
conodont b
conodont a
If the order is invariably, worldwide in this pattern, then I KNOW that
Conodont X is younger than w because the layer containing X must have been
deposited AFTER the layer containing w.
So when I can attach a radiometric date to a given layer say the layer
containing conodont w (345 myr) and r(352 myr), then I know that s and T
must be between those ages. Similarly, for the amphibians, if I can find a
terrestrial or estuarine deposit between two worldwide biostratigraphic
horizon whose associated radiometric dates average at 364 and 360 myr
respectively, then I know that the deposit is somewhere around 362 myr old.
The datings are done on items like volcanic ash which is a geologically
instantaneous deposit, or a lava flow, which is also an almost instantaneous
deposit but not as much as a bentonite(ash) bed.
Can this ordering of fossil species be due to a global flood? No. Floods
and water in general can only sort things according to size and specific
gravity. Often the sizes of index fossils range from small to large to
huge, but the species are still sorted. The best case is of the ammonites
of the jurassic. juvenile and mature specimens are found at each level but
each level ONLY contains specimens with a peculiar suture pattern on their
shells. Floods can't sort things according to how they look, only on their
size and density.
It is the worldwide vertical distribution of the same suture shape or the
same graptolite or conodont pattern that allows us to escape the charge of
circularity that creationists often claim.