The%20Burgess%20Shale

1
The Burgess Shale

• A Window on the
• Cambrian Explosion

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Konservat Lägerstatte

• Konservat preservation
• Lägerstatte treasure house
• Konservat Lägerstatte a location or
  stratigraphic unit with unique and remarkable
  preservation of fossils
• Fossils may be uncommonly abundant or rare
• Fossils are typically articulated
• Soft tissues may also be preserved

3
Burgess Shale

• Middle Cambrian Shale deep, dysoxic
• Yoho National Park
• Canadian Rocky Mountains
• The worlds most important Lägerstatte?

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The Cambrian Explosion

• Widespread appearance of abundant fossils
• Evolution Explosive Adaptive Radiation
• A Cambrian arms race? or Creation of Habitat
  Passive Margins of Rifted Rodinia
• OR
• Taphonomic Event - Made possible by development
  of shells
• Diverse taxa develop ability to make shells at
  once
• Chemical threshold in oceans? Atmosphere?
• OR ALL OF THE ABOVE????

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The Burgess Lägerstatte

• Excellent preservation
• Preservation favored by
• Fine grained sediment
• Anoxic to dysoxic environment
• Obrution Events rapid burial of live organisms
• Unique Organisms some have no modern
  descendents
• Ancestors of many extant taxa
• Wonderful Life variations and contingency

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Anomalocaris
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Marella (lace crab) andWiwaxia (an armored
tribble?)
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Opabinia, Yohoia, Sidneyia
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Halucigenia
Recent Reconstruction
First Reconstruction
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Canadia (a worm) andPikaia (first notochord)
Canadia
Pikaia
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Chenjiang Biota Maotianshan Shale

• Early Cambrian of China
• Preservation of soft-bodied biota
• Similar to Burgess Shale
• But 15 MY older!