On Mon, 16 Jun 1997 11:58:03 -0500, glenn r morton wrote:
[...]
SJ>Rather than insect having generalised mouths which natural
>selection gradually adapted to specialise with various flowers, it
>looks like the mouthparts were prepared in advance for the flowers!
GM>Have you considered two other possibilities?
>1. the mouths of insects were well adapted to feeding upon whatever
>they ate in the 100 million years prior to flowers? (If they
>weren't then the insects would have starved)
Obviously. What has that got to do with insect mouthparts being
"pre-adapted" to flowering plants which did not arise until 100 my
later?
>2. flowers evolved to match what was available at the time, namely,
>insect mouth parts which were adapted to eating other thing.?
How exactly? Why should flowers need to "match what was available at
the time, namely, insect mouth parts". If the "flowers" needed to
"match" the "insect mouth parts" they would have needed to have
matched them right away. OTOH, if they didn't need to match them
right away, then why did they develop to match them later?
Please note that there is no record of a gradual adaptation of
*anything*, including "flowers" to "insect mouthparts" in the fossil
record:
"Paleontologists had long been aware of a seeming contradiction
between Darwin's postulate of gradualism...and the actual findings of
paleontology. Following phyletic lines through time seemed to reveal
only minimal gradual changes but no clear evidence for any change of
a species into a different genus or for the gradual origin of an
evolutionary novelty. Anything truly novel always seemed to appear
quite abruptly in the fossil record. (Mayr E., "One Long Argument:
Charles Darwin and the Genesis of Modern Evolutionary Thought",
Harvard University Press: Cambridge Mass., 1991, p138, in ReMine
W.J., "The Biotic Message', 1993, p304)
Please note that I do not necessarily say that God *did* prepare
insect mouths in advance for flowers. My post heading asks it as a
question. But OTOH, as a theist, I do not rule it out, just like I
do not rule out that they may have gradually adapted by purely
natural processes:
"As a theist I believe that God exists and that God creates.
Although I insist that God has always had the power to intervene
directly in nature to create new forms, I am willing to be persuaded
that He chose not to do so and instead employed secondary natural
causes like random mutation and natural selection. I have no
preconceived idea about how long God took to produce the universe and
all its forms of life, and no objection to the possibility that the
process was sufficiently gradual to be termed "evolution." Most
importantly, I agree that the truth of these matters should be
determined by interpretation of scientific evidence --experiments,
fossil studies and the like. (Johnson P.E., "Comparing
Hostage-Takers", http://www.mrccos.com/arn/johnson/pjcht.htm)
And do you, a theist, rule out apriori that God could have prepared
in advance insect mouthparts for flowers? If so, why?
[...]
On Wed, 18 Jun 1997 20:46:33 -0500, Glenn Morton wrote:
RC>Have you considered the possibility that G-d developed them
>(mouths of insects) in advance of their need. The same argument is
>obviously true about the human brain.
GM>Let me understand your suggestion which appears identical to
>Stephen Jones'. Stephen Jones wrote:
SJ>Rather than insect having generalised mouths which natural
>selection gradually adapted to specialise with various flowers, it
>looks like the mouthparts were prepared in advance for the flowers!
GM>This argument seems to imply that God created insects with mouths
>designed for angiosperms.
See above. I do not say that "God" definitely has "created" *de
novo* "insects with mouths designed for angiosperms".
GM>But the problem with this is the simple fact that on August 23,
415,523,125 >B.C. when insects were created,
I said nothing about insects being created instantaneously. You seem
to subscribe to what Johnson refers to as "the `official caricature'
of the creation-evolution debate" (Johnson P.E., "Reason in the
Balance", 1995, pp73-74), that there is only two alternatives -
instantaneous creation or evolution?
GM>they had an IMMEDIATE need to eat something on that day. They
>could hardly wait another 100 to 200 million years for their first
>meal. Thus, are we to believe that the insects were on a 100 million
>year long diet? I doubth that anyone would go for that option. I
>would prefer to believe that their mouths were quite capable of
>eating other food.
I said *nothing* about insects not eating other plants 100 million
years before. Obviously they did. Please read again what I wrote.
GM>Secondly, Stephen Jones, description of the article really
misrepresents >what the article is saying.
Again, please read what I wrote, rather than what you *think* I
wrote. I did not "misrepresent what the article is saying" because I
did not have the article at the time, nor did I quote from it. I
simply quoted from what Piattelli-Palmarini wrote of Labandeira &
Sepkoski article:
"Finally, the conceptions of biological evolution that we have today,
with the exception of those of a very few real specialists, are
demonstrably so naive and simple-minded that it is a safe bet that
one day they will be a source of considerable embarrassment. We
shall all be embarrassed by our sweeping statements in the years to
come. Suffice it to remind the reader that insects had evolved at
least ten elaborate forms of mouthpieces, uniquely "adapted" (one
would say) to their feeding upon flowers, one hundred million years
before there were any flowers on Earth. Try to explain that with the
notion of adaptation...As I said, we shall all be embarrassed, in the
fullness of time, by the naivete of our present evolutionary
arguments. But some will be vastly more embarrassed than others."
(Piattelli-Palmarini M., "Inevitable Illusions", 1994, p195)
GM>Labandeira and Sepkoski (Science July 16, 1993 pp 310-315), are
>not at all saying that insects needed angiosperms to eat.
Nowhere did I say that "insects needed angiosperms to eat". Clearly
they did not, if they were alive and well 100 million years *before*
the angiosperms! My point was that "insects had...at least ten
elaborate forms of mouthpieces, uniquely "adapted"...to their feeding
upon flowers, one hundred million years before there were any flowers
on Earth".
Or to put it another way, flowers arose 100 million years later than
insects with parts already adapted to insect mouthpieces. There is
AFAIK no record of gradual development of flower parts to insect
mouthpieces. As a theistic realist (as opposed to a theistic
naturalist), I consider it at least possible that God may have
created (not necessarily ex nihilo), insect mouthpieces in advance of
flower parts.
GM>They are arguing against the pervasive view that the angiosperms
>increased the diversity of the insect world. They clearly show that
>the advent of the angiosperms did nothing to increase insect
>diversity. They do this in two ways. They show that the rate of
>new insect families in the fossil record actually slows down when
>angiosperms appear 140 million years ago. Their second attack on
>the view that angiosperms increased insect diversity is based upon
>the MORPHOLOGICAL argument that insect mouths can be classified into
>34 different types. All 34 types are found prior to the advent of
>the angiosperms. Thus angiosperms didn't have any effect on the
>increase in feeding morphological diversity among the insects.
>Labandeira and Sepkoski write: "After the expansion of
>angiosperms, only 1 (low estimate) to 7 (high estimate) of the 34
>mouthpart classes are know to have originated. However, these have
>poor fossil records, and only one (siphonomandibulate) is associated
>with flowering plants. Thus, by using mouthpart classes as proxies
>for ecological disparity, we conclude that virtually all major
>insect feeding types were in place considerably before angiosperms
>became serious contenders in terrestrial ecosystems. Evidence from
>the fossil record of vascular plant insect interactions also
>supports this inference." p. 314
Thanks for the quote, but what has it got to do with my argument? I
said nothing about "the advent of the angiosperms" effect on the
"increase insect diversity". The quote just confirms my main point
that "virtually all major insect feeding types were in place
considerably before angiosperms became serious contenders in
terrestrial ecosystems."
It also clearly rules out any two-way symbiotic relationship between
insects and flowering plants. The insects may have done wonders for
the flowers, but the flowers did nothing for the insects:
"The more startling interpretation that can be drawn from the data is
that the appearance and expansion of angiosperms had no influence on
insect familial diversification. Present data on the earliest
occurrences of definitive angiosperm pollen and macrofossils indicate
that these flowering plants may have originated during the
Hauterivian stage of the Early Cretaceous. However, some cladistic
analysis and fossil identifications would place the origin as early
as the Triassic, although the absence of definitive fossil material
indicates that the group could not have been abundant and
ecologically important before the Cretaceous. Whenever plants
originated, the fossil data indicates that angiosperms experienced a
tremendous radiation in all geographic regions during the Albian and
Cenomanian stages of the Middle Cretaceous. However there is no
signature of this event in the family-level record of insects.
Instead, the Fig. 4 suggest that insect diversification actually
slackened as angiosperms radiated. Even if the drop in diversity
below the exponential trend during the Cretaceous were a result of a
lack of preservation or inadequate sampling of insect fossils, the
fact remains that the post-Paleozoic radiation of insect families
commenced more than 100 million years before angiosperms appeared in
the fossil record." (Labandeira, C.C., & J.J. Sepkoski, "Insect
Diversity in the Fossil Record," Science, Vol. 261, 16 July 1993,
p313)
GM>I would also refer you to a post of mine "Angiosperms and Oil" on
>5/21/97. Angiosperms did not become a significant part of the
>world's flora until the very end of the Cretaceous, the
>Maastrichtian, about 72 million years ago. This event has often
>been used to suggest that the dinosaurs died from being unable to
>handle the poisons produced by the angiosperms which were taking
>over the world.
Sounds like the poor old dinosaurs died of everything but AIDS!
GM>Now, are you saying that God created the insects with mouths
unable to feed upon plants other than angiosperms, requiring them to
diet for more than 200 million years?
See above. It does not follow that because insects might have had
mouth parts prepared in advance by God for feeding on flowers, that
they would have had to "diet for more than 200 million years".
God bless.
Steve
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