Extensive past Distributions Floral Elements: Macrofossil
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چکیده
The past geographical positions and climates of the high latitude Southern Hemisphere land masses (New Zealand and the southern parts of South America and Australia) arc crucial to an understanding of plant evolulion migrali.on the region. A review of the macrofossil record reveals nmny exanlpies of taxa which arc present as fossils on one ur of the!;e land masses but now occur elsewhere in the Southern Hemisphere. The main examples include Austmcedrus, U!Jucedrus (Cupressaceae), Araucaria sectionColumbea (Araucariaceae) and Nothofagus subgenera Nothofar;us and Fuscaspom in Australia, Eucalyptus (Myrtaceae) and mn-Gymnostoma Casuarinaceae in New Zealand and probably South America, .'"II','lWJlfff! in New Zealand and Akania (Akaniaceae) and Dacrycwpus (Podocarpaceae) in South America. The local extinction of ihese taxa is probably dae to a variely of faciors, including climatic change, micro site changeS to the northward moverncnt of land masses, and changes in the frequency of disturbance.
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