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trees, spindles, or merely flattened blobs and discs imprinted with intriguing filigrees of creases and branches.
They appear to have had neither head nor tail; nor are there obvious circulatory, nervous, or digestive systems.
The Mistaken Point Ediacarans appeared at that critical time in Earth's history when ecosystems dominated
by multicellular animals were supplanting those dominated by microorganisms. Some were sedentary, attach-
ing themselves to the seafloor by a holdfast, much as barnacles or kelp do; others may have floated free. Re-
cently discovered specimens of Charnia, at Mistaken Point, had holdfasts and fronds nearly 2 meters (6.5 feet)
in length, making them perhaps the oldest large, morphologically complex fossils known anywhere.
It appears that most, if not all, Ediacarans disappeared just before the Cambrian explosion of multicellular
organisms. Many shelly creatures, including trilobites, emerged during this era, and these new Cambrian pred-
ators may have found the immobile Ediacarans easy pickings. The spectacular preservation of whole Edi-
acaran communities at Mistaken Point provides a snapshot of an ancient deep-sea ecosystem, which in many
respects resembles a modern sea slope community in its diversity, abundance, and spatial patterning. Further-
more, it suggests that the deep sea was colonized quickly at this early stage of animal evolution.
Mistaken Point, Newfoundland (top), preserves an ancient deep-sea community of soft-bodied, multicellular organ-
isms (bottom), the Ediacarans, variously described as ostrich feathers, Christmas trees, or spindles.
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