> An earlier, similar reply to the following was apparently lost in the
> aether. If it eventually turns up, my apologies for the duplication.
>
> In article <c271vr$7q2$0@pita.alt.net>, noway@jose.com [Uncle Davey]
wrote...
> >wiadomoci news:c24ueu$om0$1@gargoyle.oit.duke.edu...
> >> In article <c245k7$a68$0@pita.alt.net>, noway@jose.com [Uncle Davey]
> >wrote...
>
> [snip]
> >> >You raise a good point, how many loricariid fossils are there?
> >>
> >> More than zero; I recall finding refs to some when looking for
> >> info on Corydoras fossils for you in that thread a while back.
>
> [snip of a few fossil catfish refs]
>
> >Once again, not very many fossils seem to have been located bearing in
mind
> >the toughness of the exoskeleton of Loricariids and the length of time
they
> >must ahve been around.
>
> I'm not sure that we should really expect that the currently-known
> fossil record of Loricariidae [or Callichthyiidae] should be any
> better than it is.
>
> First, it seems that there aren't any large number of South American
> freshwater fossil sites of the right age range that have been
> extensively explored so far. How many fossil catfish experts are
> currently working to actually study whatever remains have been found
> to date? For all we know, there may in fact be many more fossil
> armored-catfish specimens already on museum storage shelves but
> still waiting to be described and named.
>
> Then, there are the obvious taphonomic questions:
>
> Don't many loricariids prefer to live in rocky stream habitats, not in
> places with deeply accumulating sediment? I vaguely remember
> something of the sort. If it's the case that living loricariids tend
> to avoid those places that favor fossil preservation, then it may not
> be so surprising that the known fossils of their relatives are
> relatively few.
>
> From what I've seen so far about the loricariid and callichthyiid
> fossil record, it sounds like members of both families often tend to
> disintegrate into a jumble of loose plates and spines after death.
> [An aquarist might confirm if this often happens to ones that die
> several days before being discovered and removed?] Even if the
> scattered bits of armor do preserve well, the hypothetical overworked
>
> South American paleoichthyologists might be forgiven for not spending
> much time classifying the fragmentary remains. I'm reminded of that
> earlier-cited paper which mentioned layers with concentrations of
> abundant Corydoras plates and spines, but evidently didn't bother to
> name any new fossil Corydoras species from the remains. The literature
> already cited of fossil loricariids and callichthyiids do seem to
> largely involve descriptions of loose bones [other than your one very
> complete Corydoras fossil].
>
> Anyway, it seems to me that the currently-known existence of even a
> few fossil speciments and species of these fish strongly implies the
> existence of many more individuals [and additional related species]
> that aren't yet known as fossils. Presumably, that fossil Corydoras
> species known only from a single specimen must represent only one of
> a very large number of individuals that ever lived of that species.
> [But I suppose a believer in special creationism might argue that that
> one fossil fish may well have been the only individual ever created of
> its species, and a true believer in omphalism might even suggest that
> it was specially created as a fossil, already in place in the rocks]
>
> Even an adherent of inclusive separately-created "kinds" would need
> to argue that there are many "gaps" in the fossil record between say,
> the remarkable modern diversity of Corydoras catfishes and the
> hypothetical originally-created single ancestral form of their "kind".
> The explanation will be much the same as the "evolutionist" one-- all
> the required gradual-intermediate forms must have existed in the past,
> but most are as yet unknown as fossils.
>
> cheers
>
My Omphalism Lite is still tending to believe that the fossils are from the
Flood and not from being placed there, as full omphalism would suggest.
Omphalism Lite is like a cross between Full Omphalism and YEC, taking the
strongest bits of each idea.
The way that a huge group of fishes like the armoured catfishes, and we can
also look at doradid catfishes which also have hefty plates, leave so little
trace in the record really needs some explanation by evolutionists. I quite
appreciated your argument about loricariids preferring upstream locations,
but this is far from the case with all types. The peruvian Pseudosturisoma
is a good example of the type you mentioned (picture of mine
http://www.jbc.nildram.co.uk/DCAM0307.JPG ) As you can probably see it is
very flattened and adapted to the upstream niche. The problem I had was even
that it preferred a much lower temperature than the 27 degrees I couldn't
get below in that tank over the summer, and in due course I lost the fish.
This is actually not such a typical loricariid, and in consequence harder to
keep unless you can refrigerate your tank all summer...
In fact the world's leading expert on Loricariids, Hans-Georg Evers, whom I
once about twelve years ago had the priviledge of visiting with and seeing
his fine collection of fish and tree frogs also, (he seemed to have enough
Dendrobates to put out the population of Hamburg, but I'm sure he didn't
mean anything by it, and of course if he had we'd have known about it by
now) and Ingo Seidel (whom I don't know personally - yet anyway) write in
the standard work Mergus Wels Atlas Band 1 ISBN 3-88244-062-7 on page 31 the
following: "Es ist keine leichte Aufgabe, im eng gesetzten Rahmen dieses
Buches [yeah right, it's only 816 pages on half a family] alle Lebensraeume
der Harnischwelse vorzustellen. Die verschiedenen Mitglieder der Familie
haben im Laufe der Evolution die meisten der bekannten Lebensraeume in der
Neotropis besiedelt.
Evers and Seidel then goes on for another 160 pages talking about all the
different niches of the Loricariidae all over S. America, with copius
illustrations.
<puts book back on shelf>.
So, I still think that science has a long way to go to illustrate the
evolution of Loricariidae, and in particular the eye.
The books I have are silent on the fossil record of the family, so what you
have told me is all I know about it, and it certainly seems that we have too
fragmentary knowledge to state in a scientific manner that the family
loricariidae, with its 650 odd species, some of them extremely odd, by the
way, actually evolved from anything.
I would also like to know how people posit the evolution of the
characteristic 'omega eye' of the loricariids looked like, along with the
intermediate forms.
From a Creationist perspective, I would say that in all probability there
were six kinds; Astroblebidae, Neoplecostominae, Loricarinae, Ancistrinae,
Hypostominae and Hypoptopomatinae, but if Jonathan Armbruster, the leading
ichthyologist in the field, comes up with other findings I will be the first
to wanna take those into account, since obviously the claims of science are
not to be waived aside whenever they are really based on solid evidence.
Best,
Uncle Davey
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