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Shifting
Continents and Changing Climates
The
Miocene began with a warming of the climate, before the general Cenozoic
cooling trend continued. The Atlantic Ocean continued widening. The
northward movement of Africa, the Arabian peninsula, and the Indian
subcontinent continued pushing up the Alps and the Himalaya Mountains.
Mountain-building cut off the remnants of the Tethys Ocean
from the Indian Ocean, and by the end of the epoch, Gibraltar was
connected to Africa. Thus the Tethys Ocean was separated
at both its eastern and western outlets and confined to the Mediterranean
Basin. The modern Mediterranean Sea is the last remnant
of this once-great ocean.
South America was still separated from North America. While the seas
invaded the coastal plains of North America, the Rockies and Appalachian
Mountains began uplifting again.
With the complete closure of the Tethys, circumglobal circulation
of warm waters ceased. In the oceans, great gyres or circular currents
brought warm water toward the poles and cold water toward the equator.
Fishes and whales may have used these currents to migrate seasonally
around the ocean basins. Faunal interchange between
Asia and North America continued across the Bering Land
Bridge, but by the late Miocene the bridge had been flooded. Essentially
modern patterns of ocean and atmospheric circulation developed in
the Miocene and the major landmasses came close to their present-day
positions. |
Epoch Overview |
Terrestrial Life Throughout the Miocene |
Miocene Marine Life
Shifting Continents and Changing Climates
Department of Paleobiology Home |
National Museum of Natural History Home
Smithsonian Institution Home
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