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Article: Warm band may have girdled snowball Earth.(glaciers )(Brief Article)
- Article from:
- Science News
- Article date:
- May 27, 2000
- Author:
CopyrightCOPYRIGHT 2000 Science Service, Inc. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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In the era before multicelled animals appeared some 550 million years ago, extreme cold may have clutched Earth in a death grip for millions of years. According to the controversial snowball Earth theory, the planet swung between deep freeze and feverish heat several times during a 200-million-year period preceding the multicellular explosion.
Offering an alternative to the snowball theory's ice-engulfed planet, a team of researchers from Texas and Canada now demonstrates that a swath of liquid ocean may have hugged the planet's midriff even during the chilliest episodes.
"That life survived through this episode seems to favor this open-ocean solution," ...