Terrestrial Palaeoecology and Global Change

Chapter 3. Palaeoecology
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Certain morphological phenomena in extinct plant groups seem also related to leaf
mimicry. Thus, cycadophytes constitute a heterogeneous group of Mesozoic gymnosperms
including cycads, nilssonias, bennettites and pentoxyleans. These orders, though
not closely related, are indistinguishable on the basis of their gross leaf (cataphyll) morphologies
(Fig. 26). Formal genera for fossil leaf morphotypes include representatives of
a
c
d
b
Fig. 26. Leaf convergence in the Mesozoic nilssonias (a, b) and bennettites (c-e) from the Late Jurassic to
Early Cretaceous of Bureya Basin, Russian Far East.
e