Please note my new email address: sejones@iinet.net.au (the two
i's is not a typo).
On Wed, 07 Jul 1999 21:47:35 +0000 Glenn Morton wrote:
>SJ>I am surprised that Glenn is still trotting out Longisquama's scales as an
>>example of "a partially evolved feather".
>>
>>As I pointed out to Glenn on the Reflector previously, there is no evidence
>>that Longisquama's scales were anything more than long scales, and it
>>is hopelessly out of time sequence:
>>
>>"...Longisquama is a poor-quality fossil, and the interpretation of single
>>elements is controversial. Longisquama lacks other characters-present in
>>non-avian Maniraptora-that would ally it with birds....Longisquama comes from
>>rocks about 220 million years old, creating a fossil-free gap of more than 80
>>million years before the appearance of Archaeopteryx. Any empirical measure of
>>stratigraphic fits will prefer a hypothesis of maniraptoran relationships
>>over this one." (Norell M.A., et. al., reply to Feduccia A. & Martin L.D.,
>>"Theropod-bird link reconsidered," Nature, Vol. 391, 19 February 1998,
>>p754)
>>
>>Glenn's `creationist-bashing' web page article on Longisquama at:
>>http://www.flash.net/~grmorton/longisq.htm, still contains a number of
>>inaccuracies, which I had previously pointed out to him, but which he has
>>not yet corrected.
GM>Steve [...] what you are talking about. Long gaps are quite
>normal in the fossil record. There is a 100 million gap between the first
>and second fossil caecilians. ("Rare Fossils of Enigmatic Amphibian,"
>Science News, 138, Oct. 27, 1990, p. 270.) There is a 60 million year gap
>between the first and second African turtle (Eugene S. Gaffney and James
>W. Kitching, "The Most Ancient African Turtle," Nature, 369, May 5, 1994, p.
>55.) There is nothing unusual about this at all.
Glenn cites only *two* examples of long gaps of 100 and 60 million years
and then claims they are "quite normal in the fossil record." Since there are
over a quarter of a million fossils *species* (let alone fossil individuals):
"Well, we are now about 120 years after Darwin and the knowledge of the
fossil records has been greatly expanded. We now have a quarter of a
million fossil species but the situation hasn't changed much. The record of
evolution is still surprisingly jerky and, ironically, we have even fewer
examples of evolutionary transition than we had in Darwin's time." (Raup
D., "Conflicts between Darwin and paleontology'. Field Museum of Natural
History Bulletin, January 1979, pp22, 25, in Moreland J.P. ed., "The
Creation Hypothesis", 1994, pp278-279)
to support his claim that this is "normal", he would need a lot more than
just *two* fossils!
Clearly Norell, et. al., above thought "a fossil-free gap of more than 80
million years" was not "normal"!
GM>So to have an 80 million
>year gap between a proto-feather and a final feather is no big deal.
First, Glenn is confusing a gap between whole *organisms* ("caecilians"
and "turtles") and between a morphological *structure* of an organism
("proto-feather" and "feather"). To make his case, he would need to show
examples in the fossil record of gaps of the order of 80 million years
between a proto-*structure* and the final *structure*.
Second, we *know* that there is a gap of 100 and 60 million years
between "caecilians" and "turtles" because they existed both then and
*now* as "caecilians" and "turtles". We don't know that there ever was a
gap between Longisquama and Archaeopteryx because neither existed in
the fossil record for any appreciable length of time, and moreover they are
two entirely different vertebrate *classes* (ie. Reptilia and Aves).
GM>And you are quite wrong when you say that this is out of time sequence.
>Archaeopteryx lived about 147 million years ago and it had feathers (Paul
>C. Sereno and Rao Chenggang, "Early Evolution of Avian Flight and
>Perching: New Evidence from the Lower Cretaceous of China," Science, Feb. 14,
>1992, p. 845) . Longisquama lived about 220 million years ago and possessed
>what appears to be a protofeather. Now given that protofeathers must occur
>before feathers, longisquama with its feather is quite correctly in
>sequence. [...]
What I meant by "hopelessly out of time sequence" was qualified by my quote:
>>"...Longisquama comes from rocks about 220 million years old, creating a
>>fossil-free gap of more than 80 million years before the appearance of
>>Archaeopteryx.
Thus, I meant "time sequence" in the sense of temporal continuity, not
temporal order. Clearly Longisquama is temporally prior to Archaeopteryx.
However, I agree that "hopelessly out of time sequence" is ambiguous and
I could have used a better choice of words.
>SJ>If Glenn disputes this, I wil post his web page article to the Reflector
>>and critique it again, for the benefit of new Reflectorites.
GM>Stephen go ahead. I need the publicity. It will get people to look at my
>web pages. And I appreciate that.
Glenn doesn't really dispute the main thrust of what I wrote, i.e. that his
Longisquama web page "still contains a number of inaccuracies, which I
had previously pointed out to him, but which he has not yet corrected", so
there is no need for me to critique it again at this stage.
But if I thought anyone on the Reflector actually took Glenn's Longisquama
web page seriously, I would do so. I certainly have no desire to give Glenn's
innacurate and misleading Longisquama web page any "publicity"
unnecessarily!
Steve
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Stephen E. (Steve) Jones ,--_|\ sejones@iinet.net.au
3 Hawker Avenue / Oz \ senojes@hotmail.com
Warwick 6024 ->*_,--\_/ Phone +61 8 9448 7439
Perth, West Australia v "Test everything." (1Thess 5:21)
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