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The Oligocene Ice House climate continued to cool, with dry open woodlands spreading across the North American continent. The survivors of the Grand Coupre extinction event are going from strength to strength, with dinosaur diversity almost back up to Late Eocene levels. Despite the presence of an intermittent Beringian land bridge connecting the continent to Asia, North American faunal communities contain a fair degree of endemic animals. Indeed, several groups that became extinct at the Eocene-Oligocene boundary in Eurasia have survived here; the reasons for this are not well understood at present. Although the derived Ceratopsids have vani