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Wildlife: Hey, You’re Not My Mommy!

Duane Kraemer’s lab is a through-the-looking-glass place where cows beget oxen. Is it also the last hope for species on the run?
By Paul Kvinta

Standing in the office of Texas A&M veterinary scientist Duane Kraemer is a little like stepping into a movie called The Stepford Lab: Things aren’t exactly what they seem. A kindly, white-haired 61-year-old, Kraemer beams like a proud grandfather as he shows off a collection of framed animal portraits–a beagle puppy, African elephants, a baby
baboon. Then, meandering to the inner recesses of his laboratory, Kraemer reaches into a 15-gallon steel tank. As a plume of liquid nitrogen vapor shrouds his face, he removes several thin, green plastic straws, each containing genetic material–sperm and embryos–from half a dozen species. Kraemer uses these fixings to create test-tube animal babies; in fact, most of the critters
displayed in his office are the result of such techniques.

“They say I’m trying to play God,” he says, grinning. “But really, I’m trying to help God.”

In a research effort that he calls Project Noah’s Ark, Kraemer hopes to help save the world’s endangered creatures by collecting and freezing the sperm, eggs, and embryos of every type of mammal, bird, fish, and reptile. He would use this stockpile to replenish threatened species by implanting existing animals with fertilized eggs. In a more ambitious vision that hasn’t been
tried but could be in the near future, scientists might attempt to “resurrect” an extinct species by implanting stored embryos into compatible “host” females of a different species. As a concept, Noah’s Ark represents the first species-conservation effort based entirely on bioengineering, and Kraemer’s goal is to create similar “arks” on each of the seven continents.

Kraemer admits that his vision is a long way from realization, and some environmentalists say they can’t imagine a more backward approach to conservation. “Things were alive on the real Noah’s Ark,” says Michael Wright, president of the African Wildlife Foundation. “This is sort of the freeze-dried version. It’d be like the natural history museum, with its stuffed animals,
calling itself a zoo.”

Still, Kraemer’s biggest problem isn’t critical sniping, but money. The project, founded in 1991, has always faced an uphill struggle in attracting research dollars–in part, says Kraemer, because some grant-review panels have deemed it an “unnatural” approach to conservation. Last year, Kraemer received $20,000 from the U.S. Department of the Interior and $5,000 from the Bronx
Zoo. But his projections show that to collect the genetic material for just over a dozen endangered species–and to develop reproductive strategies for each–could cost $26 million.

To push on, Noah’s Ark recently turned to the private sector, and marketers are considering everything from selling animal CD-ROMs to gathering celebrity endorsements. It’s also recruited a television consultant, Sylvia Cunliffe, who believes that the team would make for a good documentary–or even a sitcom. “There are all kinds of things behind the scenes that are humorous,”
Cunliffe attests. “This project involves looking at a lot of back ends.”

As science, Noah’s Ark involves several methods that have been used in livestock industry research for years, but rarely outside it. The key is a storage technology called “cryobanking”–freezing cells in liquid nitrogen at a temperature of minus 320 degrees Fahrenheit. Since metabolic activity, and thus cellular deterioration, ceases at that temperature, Kraemer figures that
sperm and embryos can survive frozen for hundreds of years. Part of the problem, and a focus of future research, is that most eggs cannot be banked away. “Freezing and thawing,” he explains, “can cause damage to the chromosomes.”

For now, Kraemer’s team–about 20 scientists, technicians, and graduate students–and colleagues around the country are dashing about, collecting sperm and embryos. “I work with deer hunters,” says Mark Westhusin, a veterinary scientist who runs Kraemer’s lab, “and I tell them, ‘It’s great that you put those horns on the wall, but for goodness’ sake, hang on to the
testicles.'”

The project becomes decidedly sci-fi when researchers thaw the material to produce offspring. So far, Kraemer has produced bighorn sheep using domestic sheep as mothers. Betsy Dresser of the Cincinnati Zoo has bred a rare bongo antelope using a common eland antelope, and Naida Loskutoff, a former student of Kraemer’s now at the Henry Doorly Zoo, in Omaha, Nebraska, has produced
a southeast Asian ox known as a gaur using a holstein.

There are, however, questions about the usefulness of these methods. Loskutoff points out that because the techniques of collecting, storing, and transferring genetic material differ with each species, initial research ideally involves plenty of animals from a robust population. “When you’re down to the last individuals,” she says, “you can’t do the basic studies.”

Wildlife advocates, meanwhile, seem mostly concerned that the biotech approach could someday slice into hard-to-come-by funding for habitat preservation. Kraemer counters that his strategy amounts to a “safety net” for endangered species, nothing more. “Obviously, the best way is to preserve habitat,” he concedes, “and we’d hope that we would never have to take anything out of
the bank. But we know better.”

Back in his office, Kraemer perches on the edge of the couch, scratches his head, and carefully contemplates the mechanics of truly bringing a species back from the brink. “It will be a process of triage,” he says, slowly, citing an extreme case that he thinks warrants immediate attention, the Hunter’s hartebeest. No males of the species are left, and only a single female
exists (at the Gladys Porter Zoo, in Brownsville, Texas). Kraemer could artificially inseminate the animal with hartebeest sperm stored in the Ark. But the best strategy, he explains, is to use the female as an egg producer and search for a host mother of a different species that could produce male and female hartebeests for future breeding.

“No one has brought back an extinct species yet,” he says. “But in this case, it could be time to try.”