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characters circumscribed by a particular living family or genus before reaching a conclusion about the relationship(s) of a fossil angiosperm organ. It is now understood that some organs may contain more useful characters for determining relationships than others. It is not only acceptable, but desirable, to list the available characters and how these are distributed among several living genera in a family rather than to select only a single living genus that has such characters and on this basis refer the fossil to that living genus.

New Paradigm Applied

We are moving toward a well-defined and repeatable objective character-based analysis of the angiosperm fossil record. Much of this analysis is based on the study of the anatomy and morphology of fossil plant organs. Stebbins (1950) recognized the need for this type of study when he wrote that “The method of identification is simple comparison between the fossil and the leaves of living species, but various approaches have greatly increased its accuracy.” He then cites Bandulska (1924), Edwards (1935), and Florin (1931), all early pioneers in the use of anatomy and morphology in the study of the systematics of fossil plants. However, using the new tools, it became apparent that there were many fossils that could not be related to living taxa even when such careful analyses were applied (Fig. 2 and Fig. 3). There came a time when it was necessary to give names to the various organs of fossil angiosperms that reflected their extinct nature, recognizing them as separate from any living genus (Dilcher and Crane, 1984). With few exceptions (Sun et al., 1998), workers have not yet taken such bold steps as defining and naming extinct angiosperm plant families, orders, or classes.

Rapid Changes in the Data

The great strides in developing techniques of investigation for understanding Devonian fossil plants, on the basis of seemingly nondescript structurally-preserved compressed remains (Leclercq and Andrews, 1960; Leclercq and Banks, 1962), and the excellent application of anatomy and morphology to the study of Pennsylvanian age plants (i.e., Delevoryas, 1955, and examples cited in Taylor and Taylor, 1993) influenced me to apply similar techniques to fossil angiosperms to extract as much information as possible from compressed leaves and flowers. The amount of information that can be determined about a fossil leaf, fruit, flower, pollen grain, or wood by using these techniques allows character-based comparisons to be made. These data have become available at the same time that cladistic-based (i.e., character-based) data were being assembled for the



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