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Nothing to Fear

Travels with a snake lover

March-April 2006

Few people devote their lives to creatures that have frightened and killed humans throughout history. Herpetologist Kate Jackson, Ph.D. ’02, whose work with venomous snakes has led her to remote Africa and Latin America, cannot explain her own fascination, except to say that it predates kindergarten.

The first live snake she saw, at about age five, was a Nerodia sipedon (a common water snake), which her sister accidentally threw at her in a pail of water while they played on the shore of Lake Ontario. Her parents indirectly fed the passion. “I went to a French school in Toronto, and to make sure that I learned French, they gave me books on reptiles, because they knew I would feel compelled to read them,” Jackson says.

In the Republic of Congo, Jackson exultantly dislays two (dead) cobras.
Photograph courtesy of Kate Jackson

Scientific aspirations came early. At 11, she dreamt of being curator of the Jersey Wildlife Preservation Trust in the Channel Islands—a pioneering zoo for conservation—so her parents took her there. “I wrote a letter, and the assistant curator wrote me back suggesting books I could read, and which animals would make good pets,” she says. In junior high school, a biology teacher let her keep a few pets in the classroom, and paid for an enclosure for the alligator.

Even by academic standards, Jackson’s dedication and daring fieldwork are unusual. “She is a congenital herpetologist—the woman loves serpents,” says Agassiz professor of zoology Farish A. Jenkins Jr., who sat on her dissertation committee. “We have wonderful students—one, now, who is extremely intense about hairy frogs—but Kate is truly different. Someone who loves venomous snakes has to be a little eccentric.”

Her dissertation examined the morphology and evolution of snakes’ venom-delivery apparatus. This entailed getting cobra eggs from a zoo, on the condition they not be allowed to hatch. “I didn’t know what the incubation period was—they hadn’t been studied before—and every day I was opening one egg” to document its development, she explains. “One day, when a little snake came out and spread its hood and hissed at me, I thought, ‘This is as close to hatching as I want to go.’”

Her doctoral supervisor, James Hanken, professor of biology and curator of herpetology and director of the Museum of Comparative Zoology (MCZ), praises her contributions as a “very good, popular” teacher and scientist. Using new information gained by biologists in the last 20 years about relationships among species on a molecular level, Jackson exhaustively reexamined the evolution of snakes’ venom glands, associated muscles, and fangs. She pored over eighteenth- and nineteenth-century scientific literature and conducted her own dissections, electron microscopy, and detailed embryologic studies. “It’s not like people hadn’t looked at these things before,” Hanken says, “but it’s rare to find anyone who considers all the data simultaneously.”

Jackson concluded that the earliest venom-delivery apparatus formed in the Miocene (between 25 million and 10 million years ago), and that later, three separate lineages independently evolved more sophisticated versions, a process called convergent evolution. (“The exciting thing,” Hanken adds, “now that we have more robust information on relationships, is that there seem to be more instances of parallel evolution than people had suspected previously.”) She also found significant evidence that, counterintuitively, harmless snakes evolved from poisonous ones, losing a presumed advantage.

Jackson has no interest in the role snakes have played in legends and mythology across cultures, or in their various symbolic meanings; “I just like the real thing,” she says (see “The science I do is unfashionable. I don’t study molecules in a lab. I do the kind of fundamental exploration that scientists did 200 years ago to study [the earth’s] mammals. We’re just way behind on amphibians and reptiles.” Such singlemindedness has aided her career as a scientist and explorer, but probably contributed to her unwillingness to follow Hanken’s advice about shaping her dissertation so that it would appeal to potential employers. “She’s very persistent, which is good in the field,” he says. “But she can be stubborn.”

Kate Jackson with Nerodia sipedon, the snake that started it all, Lake Ontario.
Photograph courtesy of Kate Jackson

She was known as a risk-taker within the department. In 1997, she went to the relatively stable Republic of Congo (not the war-torn Democratic Republic of Congo) to collect specimens for the MCZ. Toward the end of the trip, she had to be airlifted out of the forest to a Camaroon hospital where she spent 10 days recovering from a swamp-borne, systemic infection that began in a tiny scratch on her leg. The initial dizziness hit her while she was alone in the forest and worsened as she lurched and swayed along, following a trail of thread she had unspooled to mark a return path to the satellite camp, where she collapsed in the tent with a high fever. Two fellow researchers nursed her through the night and helped get her back to the base camp and then on to a French lumber camp, from which she was evacuated two days later.

Poisonous snakes, her specialty, offer their own set of dangers. Neurotoxins released in a bite gradually paralyze the body but leave the victim conscious until the very end. “What kills you is that the diaphragm stops moving and the heart stops beating,” Jackson explains. She has had a few close calls. She let a “playful little snake” slither through her fingers more than once before realizing that it was a baby forest cobra and laying it down “gently—no sudden moves,” embarrassed that she had misidentified the creature. “We have all taken risks and made mistakes in the field and gotten away with it,” she says. But not always. In 2001, internationally known herpetologist Joseph Slowinski, on his eleventh trip to Burma, with dozens of researchers, was bitten by a baby krait no thicker than a pencil—and up to 15 times more deadly than a cobra. He died before a rescue helicopter arrived.

Last year, Jackson approached Hanken about funding an independent research trip—a return visit to Congo. He refused. “Congo is a politically difficult place to work,” he explains. “And a dangerous place to go.” Farish Jenkins, a paleontologist, concurs. “To go to Congo alone is kind of crazy,” he says. “I mean, I go to the Arctic with collaborators and I’m armed to the teeth.”

Nevertheless, Jackson traveled in September to the remote Likouala District of northern Congo, having wrapped up her postdoctoral position at the University of Toronto. (She studied the sensory organs of three crocodiles housed in the department lab, and was the only one who would pick them up.) Once in Congo, essentially on her own, she waited three weeks in vain for a local wildlife-refuge official to give her a collecting permit. Finally she decided to pay a local Bantu chief to let her camp adjacent to the refuge with a hired cook and a guide, two tarpaulins, mosquito nets, and some pots and pans.

The trio lived together on a rare dry patch of land surrounded by flooded forests for five weeks during the rainy season and collected about 130 specimens of rare snakes, lizards, and frogs (including at least one species that may be completely new to the scientific community), all of them destined for the Smithsonian Institution, which paid for much of the trip. “Central Africa is sort of a black hole for herpetology,” says Jackson. “There are tons of places to go where no herpetologist has ever been and where, within a couple hundred kilometers, you find no overlap in species. It is that diverse.”

Money in Congo for such scientific endeavors is scarce. One professor she met at Brazzaville University had a fledgling fish collection in old mayonnaise and jam jars, but had so little formalin that only half of each creature could be preserved. “A lot of biodiversity in Africa is being lost at a terribly fast rate,” confirms James Hanken. “Many species that have not yet even been formally described are probably going to go extinct before they are named.”

Jackson herself hopes to publish a book on the largely undocumented snakes of Central Africa, research begun during her first visit to Congo. In addition to collecting for the Smithsonian, she is working with the Congolese National Laboratory on Public Health to reduce deaths from snakebite (a significant problem, because virtually no antivenoms are available). She is also seeking to train Congolese graduate students in biodiversity techniques and hoping to open a small local museum of fauna, “so they don’t have to rely on researchers like me to tell them what they’ve got.”

Every day in the field, Jackson and her guide, Etienne Bokobela, waded into the forest’s waters—chest-deep in some places—to check the fishnets they used to catch snakes that swim along the surface. “It was like Christmastime,” she says. “You get to see what you’ve got.” One day something was thrashing about furiously. Using all her strength, Jackson lifted the net and saw a snake whose head and neck were as thick as her forearm.

In her makeshift laboratory in Congo, Jackson takes tissue samples from a recent catch.
Photograph courtesy of Kate Jackson

They had a water cobra (Boulengerina annulata) that turned out to be six and a half feet long. The 24-inch tongs she used to grab snakes from the water were useless; her hemostat wouldn’t open wide enough to go around its head. She threw a snake bag at its mouth and “while it had its teeth in the bag, I went in, lightning fast, and grabbed its neck and held on tight, because it was wet and slippery,” she recalls. “If it had gotten out even a centimeter, it would have bitten me. Cobras are not as fast as vipers, but they are more clever.”

Once she had it by the throat, Bokobela cut off the netting with his machete. They carried the creature back to camp, emptied out the largest plastic supply bin they had, threw in a cloth doused with chloroform, and Jackson pushed the snake in, head-first, and shut the lid. “I was trying at that point to slow it down a little bit so I could take it out—I wanted a picture of a live snake, not a dead one,” she explains. “And that’s a dodgy decision to make, because they can recover quite quickly once they get some clean air in their lungs.” She got her photograph—and measurements. Then she killed the snake, removed a piece of its liver for DNA sequencing, injected the carcass with formalin, wrapped it in toilet paper (they were out of cheesecloth), and stored it in a plastic bag.

Jackson says convincingly that she feels no fear while working. “It doesn’t occur to me. People are frightened by different things,” she explains. “It is just in my character to be brave and reckless and independent.” On her apartment wall hangs a poster of the great British admiral Horatio Nelson, whom she has revered since she was 10. “He conquered Napoleon on the seas and he did it by ignoring orders to retreat and forging ahead,” she says. “He lost an eye and an arm, but he won the battle.”

Jackson’s recent spoils include the water cobra, a species of frog she thinks has not been mentioned in the literature since 1924, and a roadkill snake possibly not known to exist previously in Congo. At press time, she was at the Smithsonian to begin the identification and cataloging process.

Meanwhile, another trip to Congo is in store—as soon as she finds funding, and a new job. Jackson does not fit neatly into any academic spot; a museum with a strong fieldwork program might be ideal. “What I don’t want, after 25 years of knowing that I want to be a herpetologist, is to get a job teaching human physiology to undergraduates,” she says. “I’m not that interested in humans.”              

~Nell Porter Brown