Fossil Evidence of Early Tertiary North Atlantic Events Viewed in European Context

The Eocene North Atlantic land bridge:its importance in Tertiary and modern phytogeography of the Northern Hemisphere

“…I follow McKenna (1983a) in showing a marine barrier between southwestern Europe and Fennoscandia in Maps 3, 4, and 6, but this is a moot point. Similarly, the Turgai Straits isolated Fennoscandia from eastern Asia for much of the Paleogene (Hoch, 1983;McKenna, 1983a). The DeGeer route was prob-Map 3.…”

“…The second geographic modification involved the westward movement of North America. On its trailing edge this movement was powered by expansion along the Mid-Atlantic Ridge, which caused the widening of the North Atlantic and the sundering of early Tertiary ties between Europe and North America (McKenna, 1975(McKenna, , 1983aHoch, 1983). On its leading edge the westward movement contributed to the Tertiary orogenies of westem North America.…”

“…The rise and fall of this similarity parallels the projected appearance and demise of the Thulean route. Data concerning the early Tertiary vertebrate paleontology of Greenland are presently lacking (Hoch, 1983;McKenna, 1983a), curtailing a more exact description of the exchange. Botanical data.…”

“…The evidence for a Tertiary European-Asian link is scattered. The Turgai Straits (Map 5) separated Europe from western Siberia from the mid-Mesozoic to the end of the Eocene and are generally presumed to have formed a biogeographic barrier to animals (Kurt6n, 1966;Muller, 1970;McKenna, 1975McKenna, , 1983aRussell, 1975;Hoch, 1983), although the severity of this barrier has been disputed (Savage & Russell, 1983). Its eifect on plants is unclear.…”