Study suggests Alaskan tree refuge existed

August 1, 2006

U.S. scientists say they've found strong evidence an Alaskan tree refuge existed during the last glacial period, 17,000 to 25,000 years ago.

University of Illinois researchers said a genetic analysis of living spruce trees suggests that trees cannot migrate in response to climate change as quickly as some scientists have thought.

"One view is that trees were restricted to areas south of the continental ice sheets covering North America, and then migrated extremely rapidly as the climate grew warmer," said Feng Sheng Hu, an ecologist at Illinois and corresponding author of the paper. "The other view is that there was a refuge in the ice-free areas north of the ice sheets, and spruce trees expanded within those areas as the climate warmed.

"It now seems clear that a glacial refuge existed, and the trees advanced from at least two directions," he said, noting the data also suggest it is likely the migration rate was lower than previously thought.

The research appears in the early online edition of the Proceedings of the National Academy of Sciences in advance of publication.

Copyright 2006 by United Press International

Explore further: Logged tropical rainforests still support biodiversity even when the heat is on

Related Stories

Small streams have a big influence on our lives

August 7, 2017

Small streams make up 70%-80% of the total channel length of river networks, and they strongly influence downstream portions these networks. The role small streams ? known as headstreams ? play in retaining or transmitting ...

Forest 'islands' offer refuge to wintering birds

February 7, 2017

The polar vortex of 2013 and 2014 brought the coldest winter many parts of the Midwest had experienced in decades. In Dane County, Wisconsin, it was the coldest it had been in 35 years.

Recommended for you

Mountain glaciers shrinking across the West

October 22, 2017

Until recently, glaciers in the United States have been measured in two ways: placing stakes in the snow, as federal scientists have done each year since 1957 at South Cascade Glacier in Washington state; or tracking glacier ...

Carbon coating gives biochar its garden-greening power

October 20, 2017

For more than 100 years, biochar, a carbon-rich, charcoal-like substance made from oxygen-deprived plant or other organic matter, has both delighted and puzzled scientists. As a soil additive, biochar can store carbon and ...

Cool roofs have water saving benefits too

October 20, 2017

The energy and climate benefits of cool roofs have been well established: By reflecting rather than absorbing the sun's energy, light-colored roofs keep buildings, cities, and even the entire planet cooler. Now a new study ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.