Quoting Marien Faber <[log in to unmask]>:
>> "Subfossil refers to any remains of a once living organism in which
>> the fossilization process is not complete" - wikipedia
>
> This begs the question: when is the fossilization process complete?
> A more interesting question (because it can be answered) is: when
> does the fossilization process start? Arie Jansen just mailed me
> that there are actually only two states: the animal is alive, or it
> is dead. Strictly speaking all that's dead is fossil!
* wikipedia exposes the conflict we've been wrestling with - "Fossils
(from Classical Latin fossilis, literally 'obtained by digging') are
the preserved remains or traces of animals, plants, and other
organisms from the remote past."
So while 'subfossil' is defined by degree of mineralization, and
'fossil' is derived from "dug up" (i.e., embedded in some rock- or
soil-like substrate), "fossil" is defined by "remote past." Then the
"fossilization processes" listed are all modes of replacement of
original matter by something else. Remember that in the definition of
'subfossil' both Cretaceous material ('remote past'), and surface
deposits in caves (not embedded in substrate) were included.
I think these three terms are as mixed up in real usage as in
wikipedia, and that whenever "subfossil" is used it will need to be
defined by the author using it.
fred.
=======================================================
>> Date: Sun, 5 Jan 2014 09:06:34 -0500
>> From: [log in to unmask]
>> Subject: Re: [CONCH-L] Fossil Seashells and Normal seashells.
>> To: [log in to unmask]
>>
>> Quoting Patrice BAIL <[log in to unmask]>:
>>
>> > The term "subfossil" has no scientific existence and is used by
>> > collector only.
>>
>> * "subfossil" is widely used for many kinds of buried but not
>> mineralized material -
>>
>> "Subfossil refers to any remains of a once living organism in which
>> the fossilization process is not complete, either for lack of time or
>> because the conditions in which they were buried were not optimal for
>> fossilization. Such unfossilized or partially fossilized remains may
>> include bones, exoskeletons, nests, skin imprints, or fecal deposits.
>> Subfossils are often found in caves or other shelters where they can
>> be preserved for thousands of years.
>>
>> "The main importance of subfossil versus fully fossilized remains is
>> that the former contain organic material, which can be used for
>> radiocarbon dating or extraction and sequencing of DNA, protein, or
>> other biomolecules. Additionally, isotope ratios can provide
>> information about the ecological conditions under which extinct
>> animals lived. Subfossils are useful for studying the evolutionary
>> history of an environment and can be important to studies in
>> paleoclimatology.
>>
>> "Subfossils are often found in depositionary environments, such as
>> lake sediments, oceanic sediments, and soils. Once deposited, physical
>> and chemical weathering can alter the state of preservation. Small
>> subfossils can be ingested by living organisms.
>>
>> "Subfossil remains that date from the Mesozoic are exceptionally rare,
>> usually in an advanced state of decay and consequently much
>> disputed.[2] The vast bulk of the material comes from Quaternary
>> sediments, including many subfossilized chironomid head capsules,
>> ostracod carapaces, diatoms, and foraminifera." - wikipedia.
>>
------------------------------------------------------------
Frederick W. Schueler & Aleta Karstad
Bishops Mills Natural History Centre - http://pinicola.ca/bmnhc.htm
Mudpuppy Night in Oxford Mills - http://pinicola.ca/mudpup1.htm
Daily Paintings - http://karstaddailypaintings.blogspot.com/
South Nation Basin Art & Science Book
http://pinicola.ca/books/SNR_book.htm
RR#2 Bishops Mills, Ontario, Canada K0G 1T0
on the Smiths Falls Limestone Plain 44* 52'N 75* 42'W
(613)258-3107 <bckcdb at istar.ca> http://pinicola.ca/
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