WORCESTER, Mass. — In the winter chill last January, a mountain goat named Celia was wandering through the rocky highlands of northern Spain when a tree fell and crushed her to death.
With that, another species vanished from the Earth. Celia was the last remaining bucardo, a goat known for thick fur and extravagant horns, which had dwindled because of hunting, habitat destruction and landslides in its home high in the Pyrenees.
But now, in a project that has sparked debate about how best to save endangered animals, U.S. and Spanish researchers are preparing to create a new Celia by cloning one of her cells. They say that, if successful, it will be the first revival of an extinct species.
The project may sound like another sequel to "Jurassic Park," but many scientists believe that the tools that created Dolly, the famously cloned sheep, also can revive Celia and shore up the shrinking numbers of many endangered species. In fact, the tiny Massachusetts company that is working on the bucardo already has cloned an endangered animal: the gaur, a humpbacked relative of the cow from Southeast Asia.
Through cloning, the company created a gaur fetus and transferred it to an ordinary cow, which is expected to give birth on an Iowa farm any day. As the first member of an endangered species to be cloned, the new gaur will be named Noah for its symbolic role in leading the Earth's animals to safety.
Noah's birth, and the possible creation of a new Celia, could show cloning to be a powerful tool for preserving the Earth's biological diversity. With hundreds and possibly thousands of species disappearing each year, cloning advocates hope that their work will convince zoos and wildlife managers to collect and freeze cells from endangered animals. Cloning not only could revive species that disappear, they say, but save those that mate poorly in captivity, such as the giant panda, a zoo favorite.
But the idea of restocking Noah's ark with clones has drawn skepticism from several conservation groups, which fear that it could divert money and attention from what endangered animals need most: protected habitats.
"This [Celia project] is a Frankenstein's monster, cobbled together out of snips and bits, and I can't see any conservation value to it," said Karen Baragona of the World Wildlife Fund in Washington. "Animals aren't endangered because their numbers are low. It's not just a matter of making more. The problem is one of habitat loss and often of poaching. Unless you address those factors, then simply creating more of a species is not going to help."
"We don't have the necessary humility in science," warned Brent Blackwelder, president of Friends of the Earth, an environmental group. "People think they have a Godlike capacity to insert genes and do cloning without asking questions about the ecosystem impacts and moral questions about what we are doing to species."
Warnings and a Call for More Study
Blackwelder said more study is needed on whether cloning will create vibrant animals that can survive and mate properly and on whether cloned animals somehow might have traits that damage the environment. Others question the U.S.-Spanish plan to build a herd of bucardos from the genes of a single animal, warning that inbreeding has led to medical ailments in other rare animals, such as white tigers.
But scientists behind the project say it is both wondrous and useful.
"Only a few years ago, even scientists said this was impossible," said Dr. Robert P. Lanza of Advanced Cell Technology Inc. in Worcester, which cloned the gaur and is collaborating with Spanish scientists on Celia. "We are here to show them it can work."
Lanza said he and his Spanish collaborators want to make several copies of Celia and cross them with a closely related goat species to diversify the gene pool. He said that the new bucardos will fare better in the wild than the old herd, thanks to a falloff in poaching and better habitat protection by Spanish authorities.
The biological mechanisms behind cloning still are poorly understood. But in the four years since Dolly's birth in Scotland, scientists have refined the technique and learned how to apply it to a growing number of animals. If Celia's cells were frozen properly, "then the likelihood of success is pretty good," said Randall S. Prather, a cloning expert at the University of Missouri at Columbia. "I think it will work."
Cloning relies on the mysterious powers of a donor egg cell, which somehow knows how to grow from a single cell into a complex organism. The instructions for how to build the organism are contained in the DNA that lies within the egg cell.
In cloning, the trick is to remove DNA from the egg and replace it with DNA from an adult animal--from a sheep's mammary cell, for example, which was used to create Dolly. When the process works, the egg treats the foreign DNA as if it were its own and it goes on to build whatever animal is called for in the new genetic material.