Wednesday, July 15, 2015 The Nugget Newspaper, Sisters, Oregon
15
Fossils show disturbed ecosystem
By David Stauth
Correspondent
photo by Jodi sChneider MCnaMee
Charlotte oakes displays her quilted flag, signed by Gees Bend quilters.
QuILtERS: Many artists
come to Sisters for
inspiration
Continued from page 1
made by up to four genera-
tions of women in the same
family.
Bend quilter Charlotte
Oakes was excited to sign up
for their workshop for a sec-
ond time.
“I took this class last
time these incredibly tal-
ented women from Alabama
were here in 2011,” Oakes
explained. “This class excites
me because they have a new
take on what quilting is all
about; they are so brilliant.
They have taken something
that is utilitarian, like a sim-
ple quilt for your bed and
have made it into an art form,
and they’ve done it in isola-
tion, a very rural place. They
make quilting exciting, and it
frees me up! I have no sewing
machine or rotary cutter, I can
be free to use my scissors and
rip material and it’s great.”
In 2011, during a Gee’s
Bend workshop, Oakes
quilted a flag out of bits of
material and had the Gee’s
Bend quilters sign it, and
on her back label is a photo
of her and Gee’s Bend quil-
ter China Pettway with the
quilt. The words on Oakes’
label are “In the Company
of Americans.” She brought
it back to the workshop to
remind them of how incred-
ibly inspired she was and still
is by their heritage and bold
improvisational quilts.
“I put the photo of China
on my label because she
helped me with the quilt. I
quilted the top in the class and
finished the bottom of it at
home. Their way of quilting
is a whole new perspective
of looking at things,” Oakes
said. “I’m so glad China is
here this time in Sisters so I
could show her my finished
work with her photo on the
label.”
Gee’s Bend quilter Mary
Ann Pettway was on hand
helping students in the
Friday-morning workshop,
and explained to The Nugget
why she thinks Gee’s Bend
quilting is special.
“Speaking for me and all
of us; we are blessed with a
God-given gift that we put it
into fabric. Before we start
quilting, we always start out
with a song and then pray,”
Pettway said.
“People donate fabric to
us. I use a lot of bold colors
that I find and cut out a bunch
of strips and start from there,
with nothing in mind at all, it
just comes to me as I quilt.
“Even if I happen to find
some scraps on the floor I just
pick them up and use them.
Sometimes during a class
someone may throw out a few
scraps and I will get them,
its trash-to-treasure for me.
It’s just stitching three layers
together and people just seem
to enjoy our quilts. I will say
we are so happy to be back in
Sisters, we just love it here,
and the people make us feel
so welcome!”
CORVALLIS – A collec-
tion of fossilized owl pellets
in Utah suggests that when the
Earth went through a period of
rapid warming about 13,000
years ago, the small mammal
community was stable and
resilient, even as individual
species changed along with
the habitat and landscape.
By contrast, human-caused
changes to the environment
since the late 1800s have
caused an enormous drop in
biomass and “energy flow”
in this same community,
researchers reported today in
Proceedings of the National
Academy of Sciences.
The dramatic decline in
this energy flow — a mea-
surement of the energy needed
to sustain the biomass of this
group of animals for a given
amount of time — shows that
modern ecosystems are not
adapting as well today as they
once did in the past.
While climate change
is one part of this problem,
researchers at Oregon State
University and the University
of New Hampshire have found
that changes in land cover
have been far more important
in the last century. A particu-
lar concern is the introduction
and expansion of invasive,
non-native annual grasses at
the expense of native shrub-
lands. The end result, they say,
is the transformation of the
Great Basin into an ecosystem
that is distinct from its 13,000-
year history.
The study is the first of its
type to track an ecosystem-
level property, energy flow,
over many thousands of years,
and is ultimately based on the
study of owl vomit – little
pellets of undigested bones,
hair, and teeth that owls regur-
gitated over millennia into
Homestead Cave near the
Great Salt Lake. These pellets
contain the remains of owls’
prey, mostly mammals that are
smaller than a house cat.
“These owl pellets pro-
vide a really spectacular fossil
record that allows us to track
biologic changes continuously
through thousands of years,”
said Rebecca Terry, an assis-
tant professor in the College
of Science at Oregon State
University.
“They show a dramatic
breakdown in ecosystem
behavior since the late 1800s,
in a way that doesn’t parallel
what happened when major
climatic warming took place
at the end of the last Ice Age,”
she said. “The current state
is driven by human impacts
to habitat, and these impacts
have been a stronger force in
shaping the mammal commu-
nity over the last century than
just climate change.”
As the last Ice Age ended
in this region, vast lakes dried
up and vegetation made a tran-
sition from forests and sage-
brush steppe to desert shrub-
lands. But throughout these
major environmental changes,
Terry said, the “energy flow”
stayed just about constant
— as one group of animals
would decline, another group
would naturally rise and take
its place.
Since the late 1800s,
another episode of rapid
warming is under way, but
the reaction of the system has
been different.
“Species distributions
change over time, and that’s
not necessarily bad in itself,”
Terry said. “But this research
shows that ecosystem-level
properties, which are often
assumed to stay relatively sta-
ble even when perturbations
happen, are now changing as
well. The ecosystems are los-
ing their natural resilience, the
ability of one group of species
to compensate for the loss of
another.”
A major impact since the
late 1800s has been the intro-
duction of invasive cheatgrass
that displaces native bunch-
grass and desert shrub habi-
tats, while increasing fire fre-
quency, the researchers said.
They show this invasion has
also caused an observed shift
in the composition and struc-
ture of the small mammal
community, moving it toward
small, grass-affiliated species,
while larger shrub-affiliated
species have declined.
Cheatgrass thrives on dis-
turbance, and much of this
region is now affected by this
exotic annual grass. Many
human activities have facili-
tated its spread, including
livestock grazing which was
historically intense, establish-
ment of mining camps and
railroads, and an increase in
fires, the researchers said. The
Great Basin is now one of
North America’s most threat-
ened ecosystems.
Research that merges both
modern and prehistoric data
can help inform modern con-
servation biology, the study’s
authors said.
“For conservation and
management it is important
to understand when, how, and
why the responses of animals
today differ from times of
environmental change in the
past,” said Rebecca Rowe, an
assistant professor of natural
resources and the environ-
ment at the University of New
Hampshire. “The fossil record
allows us to do just that.”
Studies such as these pro-
vide a window into natural
baselines prior to the onset
of human impacts in the last
century. The effects of human
land use on ecosystems can
then be separated from the
forces of climate change today.