http://www.nature.com/nature/journal/v423/n6940/abs/423603a.html

Palaeobotany: Ice-age steppe vegetation in east Beringia
Grant D. Zazula1, Duane G. Froese2, Charles E. Schweger3, Rolf W. Mathewes1, Alwynne B. Beaudoin4, Alice M. Telka5, C. Richard Harington6 and John A. Westgate7

The landmass known as Beringia is an extensive region that existed during the Pleistocene epoch and included the land bridge between present-day Siberia and Alaska, now submerged beneath the Bering Strait. It must have been covered with vegetation even during the coldest part of the most recent ice age (some 24,000 years ago) because it supported large populations of woolly mammoth, horses, bison and other mammals during a time of extensive Northern Hemisphere glaciation, although the nature of this vegetation has not been determined1, 2, 3. Here we report the discovery of macrofossils of prairie sage (Artemisia frigida), bunch-grasses and forbs that are representative of ice-age steppe vegetation associated with Pleistocene mammals in eastern Beringia. This vegetation was unlike that found in modern Arctic tundra, which can sustain relatively few mammals, but was instead a productive ecosystem of dry grassland that resembled extant subarctic steppe communities4, 5.

1. Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
2. Department of Earth Sciences, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
3. Department of Anthropology, University of Alberta, Edmonton, Alberta T6G 2H4, Canada
4. Provincial Museum of Alberta, Edmonton, Alberta T5N 0M6, Canada
5. PALEOTEC Services, West Ottawa, Ontario K1R 5K2, Canada
6. Canadian Museum of Nature, PO Box 3443, Ottawa, Ontario K1P 6P4, Canada
7. Department of Geology, University of Toronto, Toronto, Ontario M5S 3B1, Canada

It's not Global Warming, it's Ice Age Abatement.