Gopher Guts

She's done a hippo, a giraffe, an octopus, a scorpion and a rhino fetus. She's never done a manatee, a whale, a chimpanzee or a polar bear. When any animal -- from a guinea pig to an elephant -- dies at the Saint Louis Zoo, veterinary pathologist Dr. Mary Duncan slices it open and determines the cause of death.

Only six North American zoos have pathologists on staff, says Duncan, and she is the one of the lucky few who gets to weigh panther brains, to split open iguana bellies and to strap on a personal respirator when eviscerating a bird that died from the West Nile Virus.

The zoo's Dr. Death will give a provocative lecture on her line of work, "CSI: Saint Louis Zoo," this week. Duncan will not be tracing webs of blood-spatter on the walls, à la CSI: Crime Scene Investigation's Gil Grissom. She will, however, show slides of a bird with an unusual heart defect and another avian "with too many toes," she says. "I'm trying to put all my most sensational pictures together [for the lecture]," she says with a laugh. "Hopefully it won't be too gruesome."

For obvious reasons, the zoo needs to know why animals die -- did that tufted titmouse just croak from old age, or might it have contracted a contagious disease?

Duncan's intra-animal adventures sound like a darker (and more interesting) version of Dr. Doolittle. What's it like to work on a dead, 343-pound giant turtle? "Well, with something like a tortoise of course you've got that huge shell to get into first," says Duncan, "so you could be spending two hours getting inside the shell. You can't really slash it up willy-nilly when the education department would like a nice shell at the end of the day. Now, with something like a snake, you can just cut a nice midline incision down the center of the ventral surface [underside] of the animal, and it's much easier."

Elephants, camels and giraffes are too big to make it to the necropsy room, so Duncan performs the procedure near the animal's enclosure instead. This works out for the elephants, says Duncan, because the surviving pachyderms usually host a wake!

"I have to say that one of the most touching things I have ever seen is elephants saying goodbye to another elephant that had died," she says. "We like to give them the time to do that. They seem to have so many feelings that we feel we need to let them have their grieving process. We let them have a couple of hours just to be with their [deceased] friend."

When Duncan is dissecting back in her lab, she says, she does sometimes field complaints about the rotten smells. "There are cases in the necropsy room that can leave a stench in the building for several days at a time, and I know that other people in the building will sometimes come back into my area and say, 'You're stinking up the whole building,'" she says, "but to me, there are worse smells."