Geoscience Reference
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This is a 'first discovery', because Ediacaran fossils were subse-
quently and independently 'discovered' in Newfoundland, Canada, by
the Scotsman Alexander Murray in the 1860s, and then rediscovered
in modern times in the Ediacara Hills of southern Australia by Regi-
nald Sprigg in the 1940s. In each case the fossils were treated with
scepticism, coming as they did from rocks that pre-dated the Cam-
brian System (in which 'normal' fossils such as trilobites first
appeared). Indeed, the Australian finds were first described as Cam-
brian: fellow scientists either would not believe they were fossils, or
would not believe they were Precambrian in age. The Leicestershire
fossils were simply dismissed, rather snootily, in the venerable Quar-
terly Journal of the Geological Society of 1877 as 'accidental' structures. Yet
the 'discs', 'bags', and 'fronds' represent a profound—if ultimately
failed—experiment in multicellular oceanic life.
The preservation of the Ediacarans is in itself something of a mys-
tery, for they had no hard skeletons. Perhaps their association with
microbial mats is key here, with these preserving an impression of the
undersides (and tops) of the fossils as they were buried in sediment.
Or, the microbes themselves might have formed mineral templates of
the organisms. Even more mysteriously, no one really knows what
the Ediacarans were , biologically. Many, including the fossil Ediacaria
itself, are disc-shaped, and early interpretations suggested an affinity
with jellyfish, although this now seems unlikely. The famous German
palaeontologist Adolf Seilacher likened some of them to 'quilts', bio-
logical structures with no modern analogue that may have been able
to survive in a world with few predators. The 'quilts', with their broad
surface area and lack of internal structures, may have enabled feeding
by osmosis from the surrounding water (Fig. 13). Some Ediacarans
seem to bear a closer relationship to living animals, and the disc-
shaped Aspidella , known from Newfoundland and Australia, might
have affinities to tube anemones. 87
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