Editing Cloudinidae (section)

==Paleontological importance==
Although not the first [[Small shelly fossils|small shelly fossil]] to be found, ''Cloudina'' is one of the earliest and most abundant.<ref name="Bengtson2004">{{cite book |contribution=Early skeletal fossils |author=Bengtson, S. |editor1=Lipps, J.H. |editor2=Waggoner, B.M. |title=Neoproterozoic – Cambrian Biological Revolutions |year=2004 |series=Paleontological Society Papers |volume=10 |pages=67–78 |url=http://www.nrm.se/download/18.4e32c81078a8d9249800021554/Bengtson2004ESF.pdf |archive-url=https://ghostarchive.org/archive/20221010/http://www.nrm.se/download/18.4e32c81078a8d9249800021554/Bengtson2004ESF.pdf |archive-date=2022-10-10 |url-status=live |access-date=2008-07-18 |df=dmy-all |doi=10.1017/S1089332600002345}}</ref> The evolution of external shells in the Late [[Ediacaran]] is thought to be a defence against predators, marking the start of an evolutionary arms race.<ref name="Bengtson2004"/><ref name="Dzik2007VerdunSyndrome">{{cite journal |author=Dzik, J. |title=The Verdun Syndrome: Simultaneous origin of protective armour and infaunal shelters at the Precambrian–Cambrian Transition |journal=Geological Society, London, Special Publications |year=2007 |volume=286 |issue=1 |pages=405–414 |url=http://www.paleo.pan.pl/people/Dzik/Publications/Verdun.pdf |archive-url=https://ghostarchive.org/archive/20221010/http://www.paleo.pan.pl/people/Dzik/Publications/Verdun.pdf |archive-date=2022-10-10 |url-status=live |access-date=2008-07-30 |df=dmy-all |doi=10.1144/SP286.30 |bibcode=2007GSLSP.286..405D |citeseerx=10.1.1.693.9187|s2cid=33112819 }}</ref> While predatory borings are common in ''Cloudina'' specimens, no such borings have been found in ''[[Sinotubulites]]'', a similar shelly fossil sometimes found in the same beds. In addition, the diameters of borings in ''Cloudina'' are proportional to the sizes of specimens, which suggests that predators were selective about the size of their prey. These two indications that predators attacked selectively suggest the possibility of [[speciation]] in response to predation, which is often postulated as a potential cause of the [[Cambrian explosion|rapid diversification of animals in the Early Cambrian]].<ref name=Bengtson1992/>
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Can't find ref for idea that interleaving casts doubt on McMenamin that the advent of skeletonization caused the extinction of soft-bodied Ediacaran forms
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The fact that beds containing ''Cloudina'' and other shelly fossils interleave with beds containing soft-bodied [[Ediacara biota]] casts doubt on [[Mark McMenamin | McMenamin]]'s hypothesis that the advent of skeletonization caused the extinction of soft-bodied Ediacaran forms.<ref name="McMenamin1986">{{cite book |author=McMenamin M. |year=1986 |title=The Garden of Ediacara |isbn=978-0-231-10559-0 |access-date=2007-03-08 |df=dmy-all |publisher=Columbia Univ. Press |location=New York, NY}}</ref> However there is evidence of an end-Ediacaran [[mass extinction|extinction event]], which may account for the disappearance of both ''Cloudina'' and most of the Ediacara biota, and which may have been related to the subsequent [[Cambrian explosion]] of life-forms.<ref>{{cite journal |title=Decoding the Ediacaran Enigma |author1=Brasier, M. |author2=Antcliffe, J. |journal=Science |date=20 August 2004 |volume=305 |issue=5687 |doi=10.1126/science.1102673 |url=http://www.sciencemag.org/cgi/content/summary/305/5687/1115?ck=nck |access-date=2008-07-18 |df=dmy-all |pages=1115–7 |pmid=15326344}}</ref>
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