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Removal of Exogenous Materials from the Outer Portion of Frozen Cores to Investigate the Ancient Biological Communities Harbored Inside
Published on: July 3, 2016
Arctic steppe-tundra: a yukon perspective
Science (New York, N.Y.)
|June 20, 1980
Summary
Pollen data from Eastern Beringia refutes the steppetundra hypothesis. The findings indicate a sparse arctic-alpine tundra, not a grassland, existed during the last glacial period.
Area of Science:
- Paleobotany
- Quaternary geology
- Paleoecology
Background:
- The prevailing hypothesis suggested a steppetundra or grassland ecosystem in Eastern Beringia during the Pleistocene.
- This ecosystem was thought to support extinct megafauna and early human populations.
Purpose of the Study:
- To reconstruct the paleoenvironment of Eastern Beringia using pollen stratigraphy.
- To test the steppetundra/grassland hypothesis associated with extinct vertebrates and early humans.
Main Methods:
- Analysis of the first reliable, securely dated full- and late-glacial pollen stratigraphy from Eastern Beringia.
- Interpretation of fossil flora and pollen influx data.
Main Results:
- Pollen stratigraphy contradicts the steppetundra or grassland hypothesis.
- Fossil flora indicates an arctic-alpine vegetation.
- Low pollen influx suggests sparse vegetation.
Conclusions:
- The hypothesis of a steppetundra or grassland in Eastern Beringia is rejected.
- The paleoenvironment was likely a sparse tundra, comparable to modern herb fell-field vegetation.
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