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cuticular characters, along with fruit and seed anatomy and morphology in order to research the fossil history of a family (Sheffy, 1972; Dolph, 1974, 1975; Dilcher et al., 1976b; Jones and Dilcher, 1980; Manchester, 1981, 1994; Roth, 1981; Jones, 1984; Schwarzwalder, 1986; Herendeen, 1990; Herendeen and Dilcher, 1990a, b., 1991; Herendeen et al., 1992; LAWG, 1999). The anatomical/morphological style of systematic-based angiosperm paleobotany was a distinct change from the floristic approaches that focused on paleogeographic and paleoclimatic questions and dominated the field before 1970.

This new paradigm shift opened the door for a new synthesis of the fossil record of angiosperms. New questions about the evolutionary biology of the fossil record of angiosperms could now be addressed based on detailed character-based data of living and fossil angiosperms often organized with the help of cladistic analysis (Crane 1985; Doyle and Donoghue 1986, 1993; Doyle et al. 1994). At this same time there was renewed interest in exploring the fossil plant record to determine the origin and early evolutionary history of the angiosperms (Doyle, 1969; Doyle and Hickey, 1976; Dilcher, 1979). The techniques of careful analysis and the concerted effort to open up a new fossil record of early angiosperms by the use of small, often charcoalified plant remains (Kovach and Dilcher, 1988), or fragments of cuticle sieved from sediment (Huang, 1992) from newly collected material of the Jurassic to the Upper Cretaceous were very successful. A whole new area of the study of intermediate-sized fossil plants, often termed mesofossils as opposed to microfossils or megafossils, expanded to occupy the majority of angiosperm research in some laboratories with good success (Nixon and Crepet, 1993; Crepet and Nixon 1998a, b; Gandolfo et al., 1998a, b, c; Friis et al., 1999; Crepet et al., 2000 and references cited therein). It is the success of these new techniques applied to the fossil record of angiosperms that now provides a new database from which to analyze some of the major trends in angiosperm evolution and allows us to ask new questions.

WHAT IS KNOWN ABOUT EARLY ANGIOSPERM DIVERSITY DURING THE CRETACEOUS?
New Tools of Analysis

The study of angiosperm fossils has undergone rapid and profound changes during the past 30 years as discussed in the introduction to this paper. Although the study of angiosperm fossils is only as reliable as the individual investigator, resources are now available, such as cleared leaf collections and cuticular reference slide collections from vast herbarium holdings. This allows angiosperm paleobotanists to survey the nature of



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