The%20Burgess%20Shale - PowerPoint PPT Presentation
Title:
The%20Burgess%20Shale
Description:
A Cambrian 'arms race'? or Creation of Habitat Passive Margins of ... Marella ('lace crab') and. Wiwaxia (an armored 'tribble'?) Opabinia, Yohoia, Sidneyia ... – PowerPoint PPT presentation
Number of Views:270
Avg rating:3.0/5.0
Title: The%20Burgess%20Shale
1
The Burgess Shale
- A Window on the
- Cambrian Explosion
2
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?
4
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????
5
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
6
Anomalocaris
7
Marella (lace crab) andWiwaxia (an armored
tribble?)
8
Opabinia, Yohoia, Sidneyia
9
Halucigenia
Recent Reconstruction
First Reconstruction
10
Canadia (a worm) andPikaia (first notochord)
Canadia
Pikaia
11
Chenjiang Biota Maotianshan Shale
- Early Cambrian of China
- Preservation of soft-bodied biota
- Similar to Burgess Shale
- But 15 MY older!
