Taylor, Wilson A. .
The case for a land flora in the Cambrian - ultrastructural evidence.
The past thirty years have seen increasing research and gradual acceptance of the pre-Silurian land plant record. Given the undoubtedly delicate nature of the parent plants, the microfossil record serves as the principal base of evidence for this pivotal evolutionary event. These spores of cryptic parentage are called cryptospores, and the definition of this term has become controversial with the discovery of Middle Cambrian terrestrial microfossil assemblages from across North America. Some would choose to limit the term to embryophyte spores of uncertain affinities, while others would prefer to include spores whose placement on either side of the algal/embryophyte is equivocal. The growing ultrastructural record of modern embryophytes and cryptospores is beginning to shed some light on just how far back it might be possible to trace embryophyte spores based on ultrastructure, and this talk will summarize this evidence and place it in a phylogenetic context.
1 - University of Wisconsin-Eau Claire, Department of Biology, 105 Garfield Ave., P.O. Box 4004, Eau Claire, Wisconsin, 54702-4004, USA
Presentation Type: Paper
Location: Maybird (Cliff Lodge)
Date: Monday, August 2nd, 2004
Time: 8:45 AM