Editing Fossil (section)

=== Subfossil ===
[[File:Dodo-Skeleton Natural History Museum London England.jpg|thumb|left|A subfossil [[dodo]] skeleton]]
The term subfossil can be used to refer to remains, such as bones, nests, or [[coprolite|fecal deposits]], whose fossilization process is not complete, either because the length of time since the animal involved was living is too short or because the conditions in which the remains were buried were not optimal for fossilization.<ref>{{Cite web |title = Subfossils Collections |publisher = South Australian Museum |url = https://www.samuseum.sa.gov.au/subfossils |access-date = 28 August 2020 |archive-date = 17 April 2021 |archive-url = https://web.archive.org/web/20210417141305/https://www.samuseum.sa.gov.au/subfossils |url-status = live }}</ref> Subfossils are often found in caves or other shelters where they can be preserved for thousands of years.<ref>{{cite web
 | title = Subfossils Collections
 | publisher = South Australian Museum
 | url = http://www.samuseum.sa.gov.au/subfossils/collections
 |url-status=dead
 |archive-url=https://web.archive.org/web/20110617011415/http://www.samuseum.sa.gov.au/subfossils/collections
 |archive-date=17 June 2011 |access-date=23 January 2014
}}</ref> The main importance of subfossil vs. fossil remains is that the former contain organic material, which can be used for [[radiocarbon dating]] or extraction and [[DNA sequencing|sequencing of DNA]], [[protein sequencing|protein]], or other biomolecules. Additionally, [[isotope]] ratios can provide much 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, and small subfossils can also be ingested by living [[organism]]s. Subfossil remains that date from the [[Mesozoic]] are exceptionally rare, are usually in an advanced state of decay, and are consequently much disputed.<ref>{{Cite journal | last1 = Peterson | first1 =Joseph E. | last2 = Lenczewski | first2 = Melissa E. | last3 = Scherer | first3 = Reed P. | title = Influence of Microbial Biofilms on the Preservation of Primary Soft Tissue in Fossil and Extant Archosaurs | editor-last = Stepanova | editor-first = Anna | journal = PLOS ONE | volume = 5 | issue = 10 | page = 13A |date=October 2010 | doi = 10.1371/journal.pone.0013334 | pmid=20967227 | pmc=2953520
| bibcode =2010PLoSO...513334P | doi-access =free }}</ref> The vast bulk of subfossil material comes from [[Quaternary]] sediments, including many subfossilized [[chironomid]] head capsules, [[ostracod]] [[carapace]]s, [[diatom]]s, and [[foraminifera]].

[[File:Theba geminata 08.JPG|thumb|Subfossil ''[[Theba|Theba geminata]]'']]

For remains such as molluscan [[seashell]]s, which frequently do not change their chemical composition over geological time, and may occasionally even retain such features as the original color markings for millions of years, the label 'subfossil' is applied to shells that are understood to be thousands of years old, but are of [[Holocene]] age, and therefore are not old enough to be from the [[Pleistocene]] epoch.<ref>{{cite book |last= Anand|first= Konkala|date= 2022|title= Zoology: Animal Distribution, Evolution And Development|url= https://books.google.com/books?id=NuO8EAAAQBAJ|location= |publisher= AG PUBLISHING HOUSE|page= 42|isbn=9789395936293}}</ref>