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Scientists are to extract DNA from a dodo for the first
time, raising the prospect that the animal whose name is
synonymous with extinction could be resurrected. British
experts will recover fragments of genetic material from
a preserved head and foot kept in Oxford University's Museum
of Natural History. The research will identify the closest
living relative and may pave the way to the recreation of
the species.
Ecologists, however, have warned that bringing back an
animal resembling the dodo might persuade the public that
there is no longer any need to protect endangered species,
as any creatures wiped out by man could be recreated. A
team of Oxford University experts, led by Dr Alan Cooper,
has already started to build the dodo's family tree by testing
the DNA of African and Indian Ocean pigeons, to which it
is thought to be related.
While genetic material from the extinct bird has probably
deteriorated into millions of fragments, Cooper is confident
that modern methods will reveal enough to allow it to be
compared with living species. This will show the experts
where it fits into the familty tree. "If we can find out
what the dodo's closest living relative is, it is going
to tell us a lot about where the dodo came from and how
it evolved," said Cooper.
Likely candidates include the Victoria crown pigeon from
New Guinea and the saw-billed pigeon, both very large birds
that spend their lives on the ground and rarely fly. It
could then be possible to work out the dodo's unique genes,
said Dr Charlie Shaw, an expert in ancient DNA at Durham
University. Once scientists have worked out the key genes
that made the dodo unique, they could then create genetically
engineered DNA to put into the nucleus of an egg and hatch
a dodo-like bird using one of the pigeons identified by
Cooper's survey. It would, however, be almost impossible
to recreate a perfect dodo, because its genetic code, which
survives only in tiny fragments, could never be worked out
to a sufficiently high degree of accuracy, said Dr Ken Joysey,
a palaeontologist at Cambridge University. "You only need
to get a little bit wrong to get a non-viable animal - a
single mistake could be lethal," he said.
An alternative might be to use selective breeding to create
a bird resembling a dodo. This would involve taking its
closest living relatives, inter-breeding them and selecting
the young that most exhibited the traits of a dodo. Dr Eric
Harley, a scientist at the University of Cape Town in South
Africa, is using the same method to try to resurrect the
quagga, a type of African horse wiped out by hunters 100
years ago, by selectively breeding the closely related plains
zebras that still carry the quagga's genes.
The task would be more difficult with the dodo because,
unlike the quagga, many of its genes have been lost. "With
a lot of time and a lot of breeding you could probably get
animals remarkably dodo-like, but what would be the point?"
he said.
Experts believe the dodo's ancestors flew to Mauritius
- an Indian Ocean island the size of Sussex - within the
last million years, and in the absence of predators evolved
into large, flightless animals that foraged for food on
the forest floor. The birds were first seen by Europeans
when Dutch sailors arrived in 1598. They left the dodo alone
as it was virtually inedible. However, it is believed the
dogs, pigs, rats and monkeys brought in their ships hunted
adult birds down, raided their nests for eggs and out-competed
them for food.
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