De extinction has become a plausible possibility and we have thousands of different species sitting in specimen storage around the world. Needless to say someone woke up to the symbolic significance of bringing back the passenger pigeon.
They are going to have to solve the problem that likely
killed off the pigeon. They roosted in huge vulnerable rookeries in
the south and this surely made them prime targets for the rat who
would go after the eggs and young.
However, against that day we can rebuild a breeding
stock at least.
Passenger pigeon could return, century after extinction
Originally published June 18, 2014 at 7:48 PM |
Page modified June 19, 2014 at 2:24 PM
A century ago, Martha, a red-eyed, gray and brown
bird famous as the last surviving passenger pigeon, keeled over,
marking an extinction that shook science and the public.
WASHINGTON —
It was the moment that humanity learned we had
the awesome power to erase an entire species off the face of the
Earth in the scientific equivalent of a blink of an eye: The
passenger pigeon went from billions of birds to extinct before our
very eyes.
It was one bird’s death after many. But a
century ago, Martha, a red-eyed, gray and brown bird famous as the
last surviving passenger pigeon, keeled over, marking an extinction
that shook science and the public.
A century later, Martha’s back, in a way. She
is being taken out of the file cabinets of history in a new
Smithsonian Institution exhibit this month that reminds the public of
her death and of other species that have gone extinct because of
humans. A new study published this week shows how pigeon populations
fluctuated wildly, but how people ultimately killed off the species.
Some geneticists are working on the longshot hope
of reviving the passenger pigeon from leftover DNA in stuffed birds.
“Here was a bird like the robin that everybody
knew and within a generation or two, it was gone — and we were its
cause,” Duke University ecologist Stuart Pimm said.
In the 18th and 19th centuries, the passenger
pigeon was the most abundant bird species on Earth. In 1866 in
Ontario, one flock of billions of birds, 300 miles long and one mile
wide, darkened the skies for 14 hours as it flew by overhead. Unlike
the domesticated carrier pigeon used for messages, these were wild
birds.
And famed naturalist John James Audubon once
described a mile-wide migratory flock that darkened the Kentucky
skies for days in 1813 — and brought the Louisville population to
the banks of the Ohio River with guns.
The birds were easy to catch because they stayed
together. They were considered a poor man’s food; domestic workers
complained about eating too much passenger pigeon.
“Nobody ever dreamed that a bird that common
could be brought into extinction that quickly,” said University of
Minnesota evolutionary biologist Bob Zink.
Population fluctuation
Examination of the passenger pigeon’s genetic
code shows that its population ping-ponged regularly from up to 5
billion to as few as tens of millions, said a study co-authored by
Zink in the journal Proceedings of the National Academy of Sciences
released Monday.
The passenger-pigeon population probably swelled,
crashed and recovered cyclically over the past million years, based
on climate, food and other factors, the study said. By the late
1800s, the bird population may have been in a down cycle that was
exacerbated by overhunting and land clearing.
Indeed, the chief causes of the extinction —
cutting down Eastern U.S. forests and hunting — were man-made, Zink
said. “Passenger pigeons always reached lows like this, it’s just
this time their luck ran out because we were around,” Zink said.
By 1900, there we no passenger pigeons left in
the wild. By 1914, there was just 29-year-old Martha — named for
Martha Washington — at the Cincinnati Zoo & Botanical Garden.
People lined up to see her. She was a star.
On Sept. 1, 1914, Martha was found lying on the
bottom of her cage. The passenger pigeon was officially extinct. It
had gone from billions of birds to zero in about one century,
probably less.
It was the first public extinction, something
people used to think happened only to relics of the past such as
dinosaurs, or critters stuck on islands such as dodos, Pimm and other
scientists said.
“This was a real wake-up call for the public
and frankly for scientists, too,” said Helen James, curator of
birds at the Smithsonian’s Natural Museum of History.
“Ornithologists studied birds and they didn’t really think of
species becoming extinct.”
But they did. And Martha was put in a 300-pound
block of ice and shipped to Washington, D.C., and the Smithsonian.
She was stuffed and mounted, and continued as a star. When she
traveled back to Cincinnati or to San Diego for a big conservation
conference, she flew in a first-class seat.
But her star faded. For the past 15 years, she
has been in a drab metal filing cabinet in the bowels of the
Smithsonian, stuck on the same stick with an older stuffed unrelated
pigeon named George. They were separated Monday. George was put back
in storage and a prettied-up Martha was ready for a comeback. An
exhibit on her extinction and the 100th anniversary opens June 24 at
the Smithsonian.
DNA resurrection
If scientists can figure it out, there may be a
bigger comeback in the offing. The passenger pigeon is the prime
candidate for something new: de-extinction.
Some top geneticists in a nonprofit are looking
to see if they can create living versions of the passenger pigeon, by
editing the DNA of the closely related band-tailed pigeons, growing
those birds from embryo and breeding them. It would cost millions and
take at least a decade, said Ben Novak, lead researcher of the group,
Revive & Restore of San Francisco.
Pimm and Zink don’t like the idea, ethically or
practically.
Novak sees a world on the verge of a mass
extinction of many species and feels something has to be done about
it. Reviving some long-lost species may offer “a type of justice
for what we’re doing now” and also teach people, “It’s so
much easier to keep something alive than to bring it back to life.”
Material from Los Angeles Times is included in
this report.
No comments:
Post a Comment