By Richard Black
BBC News website environment correspondent
A conservation institute in the United States has produced wildcat kittens by cross-breeding cloned adults.
Eight wildcat kittens have been born at the Audubon Center from three cloned parents
The Audubon Center for Research of Endangered Species says this is the first time that clones of a wild species have bred.
Eight kittens have been born in two litters over the last month, and all are apparently doing well.
The researchers say this development holds enormous potential for preserving a range of endangered species.
The litters were born to separate mothers, but share a father.
On 26 July, a female called Madge bore five kittens, which were followed on 2 August by three born to Caty; Madge and Caty are both clones of a further female, Nancy.
The father of all eight kittens is Ditteaux, cloned from Jazz.
"By improving the cloning process and then encouraging cloned animals to breed and make babies, we can revive the genes of individuals who might not be reproductively viable otherwise, and we can save genes from animals in the wild," commented Dr Betsy Dresser, who led the scientific team at the Audubon Center in New Orleans.
Ditteaux, a cloned wildcat, fathered all eight kittens
The Center has been working with the African wildcat (Felis libyca) for several years, producing kittens via in-vitro fertilisation in 1999 and the first clones in 2003.
The animals are somewhat larger than a typical domestic cat, and many have a domestic-style tabby coat; though not endangered, they are a useful "model organism" for developing techniques which the researchers hope could one day be used to help preserve species at risk of extinction.
Of real value?
Not all conservationists believe that cloning has much value in preserving threatened species.
WILD CLONES - TIMELINE
1996: Dolly the sheep born - first mammal cloned from adult cell
2001: gaur (wild ox) born to cow surrogate - dies within days
2001: birth of cloned mouflon lamb, rare European breed
2003: banteng (threatened Javanese cattle) clone born to surrogate
2003/4: African wildcats Madge, Caty and Ditteaux born - parents of new kittens
"While cloning is an intriguing scientific breakthrough that may enhance captive breeding in the years to come, it currently has no value for conservating endangered species in the wild," said Dr Susan Lieberman, director of WWF's Species Programme.
"Cloning does nothing to reduce the most pressing threats to endangered species and their habitats; conservation requires work on entire populations and their habitats."
If it is to play a role in conservation, the process of cloning can only be part of the story; it also has to be shown that the clones could breed normally once re-introduced to the wild.
That is what the Audubon team believes it has done, though other tests await over the coming years.
First will be a long-term programme to monitor the animals' health, and second an assessment of their behaviour, including the development of normal hunting skills.