January 22, 1999
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Editor: Cheryl Dybas
Contents of this News Tip:
A majority of Americans think computer mistakes due to the Year 2000
issue will cause only minor problems for themselves or in general, but
nearly half of Americans responding to a recent Gallup poll said they
would avoid travelling on airplanes or around January 1, 2000.
The same national questionnaire reports Americans think possible "Y2K" computer
glitches will have little or no effect on the nation's economy, yet nearly
two-thirds of those polled say they will seek extra confirmation of bank
account, retirement fund or other financial records. The poll also showed
more than two-thirds of those polled believe "Y2K" computer problems will
last several weeks to several months, and possibly as long as a year.
George Strawn, the National Science Foundation's (NSF) Computer Networking
Division director, stresses that American industry, government and academia
largely are aware of what they need to do to be fully prepared. Strawn
believes there is no need for worry or concern, but that anyone with a
home computer needs to review the manufacturer's instructions and warranties
to see if any corrective measures are necessary. [Bill Line]
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A long-term study of blue grama grass, an important source for grazing
animals in the prairies of Colorado, shows how global warming can destabilize
an ecosystem by giving invading plants an advantage over native plant
life. The study was conducted by ecologists working through the NSF's
Long-Term Ecological Research (LTER) program.
The Shortgrass Steppe LTER site in north central Colorado provided Colorado
State University researchers Rich Alward, Jim Detling and Dan Milchunas
a place to observe how climate change can affect an ecosystem.
In these grassy ranges of Colorado, a long growing season primarily
benefits plants that do well in cooler weather. Here, the plants most
likely to benefit from a longer growing season are often the weeds and
non-native grasses that can sprout quickly after the winter thaw begins.
These cool-season plants can then take advantage of space and water resources
before the warm-season grasses begin growing in earnest. The warm-season
grass in question is blue grama, a plant that provides an important food
source for both cattle and wildlife in the area.
Since blue grama covers nearly 90 percent of the shortgrass steppe,
its loss can have serious consequences on the strength of the ecosystem.
Blue grama has flourished in the grasslands due, in part, to its ability
to survive both long periods of drought and constant grazing. If cool-season
plants outgrow blue grama, it is questionable that they can survive these
same conditions.
According to Detling, increases in the growing season may ultimately
destabilize the shortgrass ecosystem, possibly resulting in the loss of
important grazing land. [Cheryl Dybas]
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The ancestors of major groups of animal species began populating Earth
more than 600 million years earlier than indicated by their fossil remains,
according to the largest study ever on the subject using gene sequences.
The recently completed study at Penn State University, funded in part
by NSF, suggests that animals have been evolving steadily into different
species for at least 1200 million years—which challenges a popular theory
known as the Cambrian Explosion that proposes the sudden appearance of
most major animal groups, known as phyla, 530 million years ago. A paper
describing the research is published in the January 22, 1999, issue of
the Proceedings of the Royal Society of London (Series B) by Penn State
scientists Daniel Y.-C. Wang, Sudhir Kumar, and S. Blair Hedges.
To gauge the pace of evolution, the research team tested hundreds of
gene sequences to find those that developed mutations at a constant rate
over time. "Because mutations start occurring at regular intervals in
these genes as soon as a new species evolves—like the ticking of a clock—we
can use them to trace the evolutionary history of a species back to its
actual time of origin," Hedges explains.
"Not only are all these genes telling us that a wealth of animal species
in at least three phyla were already on Earth millions of years before
their fossils start appearing," Hedges says, "but they also are telling
us when three of the major kingdoms of living things -- animals, plants,
and fungi—first diverged from a common ancestor and began evolving down
separate evolutionary paths." That date—about 1.6 billion years ago—is
the earliest yet obtained by gene studies for this evolutionary event.
[Cheryl Dybas] Top of Page
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