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Devonian Landscape Heterogeneity Recorded by a Giant Fungus
(Geological Society of America, 2007)
The enigmatic Paleozoic fossil Prototaxites Dawson 1859 consists of tree-like trunks as long as 8 m constructed of interwoven tubes <50 mm in diameter. Prototaxites specimens from five localities differ from contemporaneous ...
Organic Chemical Differentiation Within Fossil Plant Cell Walls Detected with X-ray Spectromicroscopy
(Geological Society of America, 2002)
Organic matter preserved in cell walls of permineralized plant fossils was analyzed by using scanning transmission X-ray microscopy and spectroscopy at energies near the 1<i>s</i> absorption edge of carbon. Microchemical ...
Chemical Evidence for Cell Wall Lignification and the Evolution of Tracheids in Early Devonian Plants
(University of Chicago Press, 2003)
Anatomically preserved land plant fossils from the Lower Devonian Rhynie Chert contain conducting tissues with cells that range from dark-colored, elongated cells without secondary wall thickenings to tracheids similar to ...
Nondestructive, in situ, Cellular-scale Mapping of Elemental Abundances Including Organic Carbon in Permineralized Fossils
(National Academy of Sciences, 2001)
The electron microprobe allows elemental abundances to be mapped at the µm scale, but until now high resolution mapping of light elements has been challenging. Modifications of electron microprobe procedure permit fine-scale ...
Evolution of Xylem Lignification and Hydrogel Transport Regulation
(National Academy of Sciences, 2004)
In vascular plants, the polysaccharide-based walls of water-conducting cells are strengthened by impregnation with the polyphenolic polymer lignin. The fine-scale patterning of lignin deposition in water-conducting cells ...
Evolution of Developmental Potential and the Multiple Independent Origins of Leaves in Paleozoic Vascular Plants
(Paleontological Society, 2002)
Four vascular plant lineages, the ferns, sphenopsids, progymnosperms, and seed plants, evolved laminated leaves in the Paleozoic. A principal coordinate analysis of 641 leaf species from North American and European floras ...