Chapter 5. The Cambrian Explosion

1. Substantial comments or mini-essays, often with links of their own. They are laid out in the order I deal with them in the Chapter.
2. Pages that consist almost entirely of Web links on a particular topic.
3. Small comments and asides ("footnotes", if you like), including useless information, again arranged in order. I have listed them under page number as well as topic.

Mostly Web links

Ediacaran Animals

The Beginning of the Cambrian: Small Shelly Fossils

• Tommotian Stage of Lower Cambrian (530 Ma)
• Cambrian Stratigraphy
• Pam Gore's lecture notes on Precambrian/Cambrian Transition
• Fossilized embryos from the Precambrian/Cambrian boundary.

Larger Cambrian Animals

Trilobites

• Trilobite page from Sam Gon III. Looks great!
• Trilobite page from Kirsty Pitcher, in Oxford, England.
• Trilobites, from the UC Berkeley site.

The Burgess Fauna

When Was The Origin of Metazoans

• A 1997 essay by Alan Jay Kaufman that describes some relevant research on molecular evolution.
• Evolution deep in the Precambrian?, again based on molecular clocks. Press release from Penn State University, January 1999.
• The Cambrian explosion may mark an ecological revolution, rather than a time of extraordinary rapid genetic change. Evidence for this view is beginning to accumulate. For example, Precambrian (Ediacarian/Vendian) rocks in China have now yielded sponges and embryos of more than one metazoan group, even though no adult skeletonized fossils have yet been found. Even if Xiao et al. (2000) are correct that the embryos are all cnidarian, this is still a metazoan group contemporary with the Ediacaran fossils.

Bilaterians

The reference list for Chapter 5, 4th Edition, with associated Web links

Page last updated June 7, 2004.

All links last checked, October 1, 2005.

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