Air Date: Week of December 17, 1999

At the Audubon Institute for Research of Endangered Species in New Orleans a domestic house cat gave birth to an African wildcat whose embryo had been frozen and then implanted in the house cat's womb. Host Steve Curwood speaks with Director of Research, Dr. Betsy Dresser about this procedure as a safety net for endangered species.

Transcript

CURWOOD: It's Living on Earth. I'm Steve Curwood. Scientists at the Audubon Institute Center for Research of Endangered Species in New Orleans are making news. They have successfully brought the embryo of a rare species of African wildcat to full term in the womb of a common domestic shorthaired cat. Eggs and sperm were taken from the African cats, mixed together in the lab, and eight resulting embryos were frozen. Later, some were implanted in the tabby, which gave birth about three weeks ago. Long used for livestock breeding, this technique could have dramatic implications for the future of endangered animals. That's according to the center's director of research, Betsy Dresser.

DRESSER: You know, in the future, we don't know what technologies are going to be out there for use of viable DNA, or living DNA. And so, what we're trying to do with endangered species is bank as much genetic diversity as we can through frozen embryos or frozen sperm, and so that we can recall it if we ever really need it.

CURWOOD: Explain to me more about this concept of a frozen zoo.

DRESSER: You know, if you have embryos frozen from a species, and you know how to thaw it and you can identify a surrogate, you can essentially keep a species from going extinct. And in my mind, that's a very powerful tool. So, you know, I would hope that we could do this with many, many species, and it provides a safety net for them.

CURWOOD: How many species do you have now?

DRESSER: We've got about 500 animals in our frozen zoo right now.

CURWOOD: Embryos of 500 different endangered animals?

DRESSER: Either embryos or sperm, right.

CURWOOD: And could you grow out all of those? Do you have the surrogate moms for them? Or you don't know yet?

DRESSER: We don't know yet, for everything. And actually, that's why we're doing this. And trying to identify these common surrogates.

CURWOOD: The housecat and the African wildcat aren't that very different. What about doing this with species that aren't quite so similar?

DRESSER: Well, you know, I don't think we'll ever put a giraffe in an elephant, for example, because I think there has to be a lot of close relatedness. But there are 23 species of small exotic cat, and most of them are endangered. So, if we could use the domestic housecat as a surrogate for even half that many exotic cats, I think we would have made a contribution, really, to save small exotic cats.

CURWOOD: Now, what about the ethical concerns about this type of work? I mean, nature doesn't have one species get incubated by another.

DRESSER: No, but I don't think nature counted on mankind doing to wildlife or endangered species what we've done. If mankind sits back and thinks about, you know, the damage really that's been done, and the extinction of so many species because of our species, I think the ethical question comes there.

CURWOOD: Now, what if people hearing us, or hearing about your work, say, "Hey, I don't have to worry so much about species going extinct or being endangered. Because they'll be frozen. We'll bring them back some time in the future when we have the technology to grow them out again."

DRESSER: I think everyone needs to realize that this technology is very, very much in its infancy. You know, there's only been maybe 10 or 12 animals, endangered animals, produced from any kind of frozen embryos or frozen sperm. And so, you know, we don't know enough yet to be able to say that all these species are protected. I think this is just one tool in a toolkit of a lot of different possible ways in the future of saving endangered species.

CURWOOD: Tell me a little bit about this housecat. What's her name?

DRESSER: Her name is Cayenne, like the pepper.

CURWOOD: Uh huh. (Laughs) And her baby's name?

DRESSER: Her baby's name is Jazz, for New Orleans, of course.

CURWOOD: You know, this story reminds me of the ugly duckling, the mother duck who found herself with a swan. I mean, this mother must think that her baby's got, well, some cosmetic problems?

DRESSER: (Laughs) Well, he doesn't look too much different from her. But, you know, he hissed at us when he was two days old. He's pretty feisty, so she probably thinks she's just got a lot of trouble on her hands.

CURWOOD: Betsy Dresser is director of research at the Audubon Institute Center for Research of Endangered Species in New Orleans. Dr. Dresser, thanks for speaking with us today.

DRESSER: You're very welcome. Thanks for your interest.