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ET atter engang modbevist
Fra : Jahnu


Dato : 20-11-08 17:32

Trilobite Had Visors

Many times when new discoveries are made, in their reports scientists
don't mention the transitional animal form at all. This also happened
not so long ago when Richar Fortey et.al. discovered that the
trilobites in Morocco had visors, their eyeballs extended upward in
two columns from the head, and contained vertically-stacked lenses
(about 560 in all), "a commanding field of view that was entirely over
the sediment surface on which the animal lived.The compass of the eyes
shows that they commanded a 360-degree sweep in the horizontal plane.
The high elevation of the eyes meant that the animal could even see
backward over its thorax."

"This eye is different from that of other trilobites in that the
palpebral lobe above it extends outward over the whole of the visual
surface as an eyeshade or visor. Because the corneal surfaces are
spherical, they are vulnerable to picking up stray light from
directions other than the favored one normal to the surface of the
eye. But the eye is so straight-sided that this hood effectively
protects the visual surface from glare derived from surface light. We
were able to demonstrate this by shining a parallel beam down from
above the eye; the eyeshade efficiently cuts out incident light from
this direction."[1]

Further, the authors of the article commented: "trilobites already had
unusually sophisticated eyes with lenses made out of the mineral
calcite." This means that many trilobites had binuclear vision and
"internal structures of high magnesium calcite that helped the lenses
to focus more precisely by eliminating sources of 'fuzziness,' such as
spherical aberration."

But what does all this mean? According the authors, all this indicates
that the trilobites were day-time-active or diurnal and not nocturnal
or night-time-active. As they remarked, "An eyeshade is of little use
in the dark." Moreover, in his previous work prof. Fortey said:

"We know that the first trilobites already had a well-developed visual
system. Indeed, the large eyes found in the genus Fallotaspis, from
Morocco, prove that sophisticated vision goes back at least 540
million years to the Cambrian period"[2]

"Euan Clarkson [of the University of Edinburgh] and University of
Chicago physicist Riccardo Levi-Setti discovered that something
strange had happened to the calcite in the lower part of each Phacops
lens: magnesium atoms were present in just the right quantity to
correct the spherical aberration. For every bend to the left, there
was a compensating bend to the right. This corrective layer made a
bowl within the lens; the trilobite had thus manufactured what modern
opticians term a doublet. The animals with these eyes may have seen
more complete images of an object than their hexagonal-lensed fellows.
All this [supposedly occurred] 400 million years
ago" (Ibid. 72).

Comment: The sudden appearance and astonishing complexity of
trilobite's eyes is putting a question mark to the established
evolution theory and favors the concept of intelligent design.

NOTES:
1. Fortey, R. and Chatterton, B. (2003). A Devonian Trilobite with an
Eyeshade. Science 301(Sept. 19), 1689.
2. Fortey, R. (2000). "Crystal Eyes." Natural History 109,
no. 8: 68-72.


http://krishnascience.com
http://harinam.net
http://tinyurl.com/5d5le9

 
 
Thomas Hejl Pilgaard (21-11-2008)
Kommentar
Fra : Thomas Hejl Pilgaard


Dato : 21-11-08 21:42

Jahnu <jahnudvip@gmail.com> declared in:
dae4575e-feca-4c28-9daf-f84bf0018ae1@d42g2000prb.googlegroups.com :

> Comment: The sudden appearance and astonishing complexity of
> trilobite's eyes is putting a question mark to the established
> evolution theory and favors the concept of intelligent design.

Så nu er ID-tilhængerne retireret fra tanken om en oprindelig designer,
til tanken om en ... "ting", der løbende gennem verdenshistorien, en
gang i mellem får nye ting til at opstå i de allerede eksisterende
levende organismer?

Forandringer skyldes således ikke mutationer, men at gud lige svinger
tryllestaven en gang i mellem?

"Abra-kadabra... Du er nu en hest - med STRIBER!"



Bo Warming (22-11-2008)
Kommentar
Fra : Bo Warming


Dato : 22-11-08 04:58

"Jahnu" <jahnudvip@gmail.com> skrev i meddelelsen
news:dae4575e-feca-4c28-9daf-f84bf0018ae1@d42g2000prb.googlegroups.com...
> Trilobite Had Visors
>
> Many times when new discoveries are made, in their reports scientists
> don't mention the transitional animal form at all. This also happened
> not so long ago when Richar Fortey et.al. discovered that the
> trilobites in Morocco had visors, their eyeballs extended upward in
> two columns from the head, and contained vertically-stacked lenses
> (about 560 in all), "a commanding field of view that was entirely over
> the sediment surface on which the animal lived.The compass of the eyes
> shows that they commanded a 360-degree sweep in the horizontal plane.
> The high elevation of the eyes meant that the animal could even see
> backward over its thorax."
>
> "This eye is different from that of other trilobites in that the
> palpebral lobe above it extends outward over the whole of the visual
> surface as an eyeshade or visor. Because the corneal surfaces are
> spherical, they are vulnerable to picking up stray light from
> directions other than the favored one normal to the surface of the
> eye. But the eye is so straight-sided that this hood effectively
> protects the visual surface from glare derived from surface light. We
> were able to demonstrate this by shining a parallel beam down from
> above the eye; the eyeshade efficiently cuts out incident light from
> this direction."[1]
>
> Further, the authors of the article commented: "trilobites already had
> unusually sophisticated eyes with lenses made out of the mineral
> calcite." This means that many trilobites had binuclear vision and
> "internal structures of high magnesium calcite that helped the lenses
> to focus more precisely by eliminating sources of 'fuzziness,' such as
> spherical aberration."
>
> But what does all this mean? According the authors, all this indicates
> that the trilobites were day-time-active or diurnal and not nocturnal
> or night-time-active. As they remarked, "An eyeshade is of little use
> in the dark." Moreover, in his previous work prof. Fortey said:
>
> "We know that the first trilobites already had a well-developed visual
> system. Indeed, the large eyes found in the genus Fallotaspis, from
> Morocco, prove that sophisticated vision goes back at least 540
> million years to the Cambrian period"[2]
>
> "Euan Clarkson [of the University of Edinburgh] and University of
> Chicago physicist Riccardo Levi-Setti discovered that something
> strange had happened to the calcite in the lower part of each Phacops
> lens: magnesium atoms were present in just the right quantity to
> correct the spherical aberration. For every bend to the left, there
> was a compensating bend to the right. This corrective layer made a
> bowl within the lens; the trilobite had thus manufactured what modern
> opticians term a doublet. The animals with these eyes may have seen
> more complete images of an object than their hexagonal-lensed fellows.
> All this [supposedly occurred] 400 million years
> ago" (Ibid. 72).
>
> Comment: The sudden appearance and astonishing complexity of
> trilobite's eyes is putting a question mark to the established
> evolution theory and favors the concept of intelligent design.

At et evolutionært mellemstadig kan være med eller uden syn
KAN ALDRIG VÆRE BEVIS


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