The effects of glaciation described above by Good were much less severe for China. If the idyllic sequence of which he writes, though perhaps modified, persisted there, it can help explain how for some species that country served as a place of last refuge. Ginkgo biloba, a gymnosperm, for example, is the sole survivor there of a genus formerly widespread in the world and with an immensely long fossil history dating back nearly 200 million years. Seward (1938) charts the decline of the gingkophytes — the close relatives of Ginkgo. By the beginning of the Oligocene only 2 out of 19 genera remained. The decline continued into the Miocene and they disappeared in the Americas. In Europe Ginkgo appears to have survived into the Pliocene and then succumbed to the effects of glaciation. Wilson (1929) attributed its survival in China to protection in Buddhist monastery gardens, but this appears to be unfounded. What are surely more relevant are the benign effects of having escaped the ravages of glaciation.
KeywordsEurope Rubber Sandstone Shrinkage Shale
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