Suggested Phylogenies
Further information: Debate about Cambrian Lophotrochozoans
Since 1995 several phylogenies, or evolutionary "family trees", have been suggested for these organisms. The position of Wiwaxia is highlighted, since the position of this organism has been central to the debate since 1990.
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Siphogonotuchida
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MOLLUSCA
(crown group)
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"Siberian halkieriid"
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Canadia
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ANNELIDA
(crown group)
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Wiwaxia
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Thambetolepis
(halkieriid)
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Halkieria evangelista
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BRACHIOPODA
(crown group)
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Cladogram: Conway Morris & Peel (1995)
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ANNELIDA
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? Kimberella
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Odontogriphus
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Wiwaxia
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Halkieriids
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Neomeniomorpha / Solenogasters
(Aplacophora)
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Polyplacophora
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Other crown group molluscs
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Cladogram: Caron, Scheltema, et al. (2006)
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Kimberella
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Odontogriphus
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Wiwaxia
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Siphogonotuchida
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Orthrozanclus
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Halkieriids
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Canadia
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ANNELIDA
(crown group)
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Micrina
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BRACHIOPODA
(crown group)
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Kimberella
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Odontogriphus
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MOLLUSCA
(crown group)
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Canadia
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ANNELIDA
(crown group)
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Micrina
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BRACHIOPODA
(crown group)
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Cladograms: Conway Morris and Caron (2007) — Hypothesis 1 (left) and 2 (right).
The authors regard Hypothesis 1 as better supported by the evidence, but not robust.
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Kimberella
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Odontogriphus
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"Halsiphonids"
(halkieriids +
siphogonotuchids)
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Wiwaxia
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Canadia
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ANNELIDA
(crown group)
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Micrina
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BRACHIOPODA
(crown group)
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Butterfield's alternative.
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