Rare earth........
Bringing Back the Tiger
Scientists Hope DNA Will Allow Cloning of Extinct Marsupial
B R I G H T O N, Tasmania, Aug. 22 — A sign by the small
enclosure near the Bonorong Park Wildlife Center
entrance says “Tasmanian tiger” but the fabled
carnivore is nowhere to be seen.
The last known Tasmanian tiger, or thylacine, died in
captivity in 1936, but a team of Australian biologists believes
the animal’s extinction may simply be a 70-year hiccup. DNA
from a Tasmanian tiger has been found and cloning is
underway.
Hope for the rebirth of the tiger — not a cat at all but a
striped marsupial wolf — lies in the murky depths of a
museum specimen jar, where a six-month-old thylacine pup
has sat preserved in alcohol since 1866.
Australian Museum director Mike Archer said he knew 15
years ago the specimen held the key to the return of the
tiger, but it was not until Dolly the sheep was cloned in
Scotland in 1997 that technology caught up with his dream.
“It became a matter of not if, but when,” Archer said.
Incubation in a Relative
In April, small samples of heart, liver, muscle and bone
marrow tissue were extracted from the preserved pup, and
a small team of evolutionary biologists in Sydney began
working to unravel the tiger’s genetic code.
Once DNA damage is assessed and repaired, the tiger’s
genetic blueprint will be inserted into the egg of a close
relative, probably the Tasmanian devil or the numbat,
another marsupial, for incubation.
While there have been similar extinct-animal cloning
projects elsewhere in the world, the Australia Museum’s
project is the first to find good quality DNA from an extinct
specimen.
But there is much work to be done and Archer said it
could take another 10 to 15 years to clone the tiger.
Experts disagree on the project’s chance of success —
with odds ranging from close to zero to 50-50.
Settlers’ Bitter Enemy
Most of what is known about thylacines is from myths and
museum exhibits, which sprung up around the world in the
1930s as the tiger headed toward extinction and zoologists
clamored for specimens. There is a skeleton in Heidelberg,
Germany, and a mounted stuffed tiger in Zurich, Switzerland.
Black-and-white photographs abound, showing a large
doglike marsupial with tan fur and black stripes across its
lower back and rump. Like the Tasmanian devil and its more
distant relative the kangaroo, the female tiger carried its
young in a pouch. The animal had a heavy, rigid tail like that
of a kangaroo.
The tigers were only seen by white settlers on Tasmania,
the island state that appears like a teardrop beneath
Australia’s southeast coast, but the predators once roamed
the mainland and the island of New Guinea, where they were
killed off by wild dogs introduced by man some 6,000 years
ago.
On Tasmania, the tiger quickly became the bitter enemy
of British settlers. It was blamed for killing sheep and other
farm animals and, after a bounty was put on its head in
1888, tiger trapping became a paying occupation.
Protest Over Cloning
In popular imagination, the tiger is plucked from extinction
with sightings reported, blurred photographs produced and
debate refired about its ability to survive undetected for
nearly 70 years, even in the virtually untouched wilderness of
Tasmania.
Sightings have even been reported from remote parts of
the southern mainland.
A far more emotional debate rages over the plan to
reincarnate the tiger through cloning. Archer has crossed
angry picket lines at his museum and his work has been
denounced by religious groups who accuse the scientists of
playing God.
“My response is that people played God when we
exterminated the animal in the first place,” Archer said
Bringing Back the Tiger
Scientists Hope DNA Will Allow Cloning of Extinct Marsupial
B R I G H T O N, Tasmania, Aug. 22 — A sign by the small
enclosure near the Bonorong Park Wildlife Center
entrance says “Tasmanian tiger” but the fabled
carnivore is nowhere to be seen.
The last known Tasmanian tiger, or thylacine, died in
captivity in 1936, but a team of Australian biologists believes
the animal’s extinction may simply be a 70-year hiccup. DNA
from a Tasmanian tiger has been found and cloning is
underway.
Hope for the rebirth of the tiger — not a cat at all but a
striped marsupial wolf — lies in the murky depths of a
museum specimen jar, where a six-month-old thylacine pup
has sat preserved in alcohol since 1866.
Australian Museum director Mike Archer said he knew 15
years ago the specimen held the key to the return of the
tiger, but it was not until Dolly the sheep was cloned in
Scotland in 1997 that technology caught up with his dream.
“It became a matter of not if, but when,” Archer said.
Incubation in a Relative
In April, small samples of heart, liver, muscle and bone
marrow tissue were extracted from the preserved pup, and
a small team of evolutionary biologists in Sydney began
working to unravel the tiger’s genetic code.
Once DNA damage is assessed and repaired, the tiger’s
genetic blueprint will be inserted into the egg of a close
relative, probably the Tasmanian devil or the numbat,
another marsupial, for incubation.
While there have been similar extinct-animal cloning
projects elsewhere in the world, the Australia Museum’s
project is the first to find good quality DNA from an extinct
specimen.
But there is much work to be done and Archer said it
could take another 10 to 15 years to clone the tiger.
Experts disagree on the project’s chance of success —
with odds ranging from close to zero to 50-50.
Settlers’ Bitter Enemy
Most of what is known about thylacines is from myths and
museum exhibits, which sprung up around the world in the
1930s as the tiger headed toward extinction and zoologists
clamored for specimens. There is a skeleton in Heidelberg,
Germany, and a mounted stuffed tiger in Zurich, Switzerland.
Black-and-white photographs abound, showing a large
doglike marsupial with tan fur and black stripes across its
lower back and rump. Like the Tasmanian devil and its more
distant relative the kangaroo, the female tiger carried its
young in a pouch. The animal had a heavy, rigid tail like that
of a kangaroo.
The tigers were only seen by white settlers on Tasmania,
the island state that appears like a teardrop beneath
Australia’s southeast coast, but the predators once roamed
the mainland and the island of New Guinea, where they were
killed off by wild dogs introduced by man some 6,000 years
ago.
On Tasmania, the tiger quickly became the bitter enemy
of British settlers. It was blamed for killing sheep and other
farm animals and, after a bounty was put on its head in
1888, tiger trapping became a paying occupation.
Protest Over Cloning
In popular imagination, the tiger is plucked from extinction
with sightings reported, blurred photographs produced and
debate refired about its ability to survive undetected for
nearly 70 years, even in the virtually untouched wilderness of
Tasmania.
Sightings have even been reported from remote parts of
the southern mainland.
A far more emotional debate rages over the plan to
reincarnate the tiger through cloning. Archer has crossed
angry picket lines at his museum and his work has been
denounced by religious groups who accuse the scientists of
playing God.
“My response is that people played God when we
exterminated the animal in the first place,” Archer said |
