Surviving the Extremes: A Doctor's Journey to the Limits of Human Endurance (13 page)

So vivid was Antonio’s description that I wondered how much more he wasn’t telling me; but I didn’t ask, and he didn’t offer. We continued on in silence.

We stopped briefly at the clearing in which Antonio had placed his basket as a marker. The cut stump of the heart-of-palm tree already had fungus growing on it. The fruit tree, with Antonio’s prodding, dropped more ripe fruits to the ground. The basket may have been hastily made, but it was strong enough to hold the half-dozen fruits that he collected and carried back to camp.

We finished the trail portion of the trip fairly quickly and would have been in camp a lot sooner had we not taken so long to cross the lake. Antonio stopped paddling midway along to listen to the water. Every so often there came a slight gurgling noise, though from where it was hard to discern. Whenever he heard it, Antonio would paddle a little bit more and then stop again. He was chasing a fish, and he
stayed at it for nearly an hour before giving up. I couldn’t imagine what fish could be worth so much effort.

Antonio’s fruits were a big hit at camp. Because of the low water level, the expedition was unable to resupply itself, and this made anything fresh really welcome. Sebastian, our liaison with the Indians, told us how lucky it was that almost all our supplies had made it through the first time. He thought it very curious that the only things the Indians said had gotten broken en route were the three bottles of rum he had packed as a surprise for us. I didn’t tell him I had seen one of them on the shelf in Antonio’s village hut.

The next morning I was awakened by a commotion and went out to investigate. An enormous red fish was hanging upright from a rope strung between two trees, its tail nearly touching the ground. It had to be at least twice Antonio’s weight and a foot taller. Antonio was standing beside it, busily cutting out fillets. It was a pirarucu, an Amazon catfish, that makes a gurgling noise when it surfaces to breathe air. Antonio had gone out on the lake at first light, waited for the fish he had heard with me in the canoe the day before, and harpooned it. The fish would add at least two or three days to our food supply and, I was sure, provide several meals for Antonio’s family. I understood why he had hunted it so patiently yesterday. I also wondered what other surprises we might be swimming with in that lake.

The extra food gave the researchers enough time to complete their studies. Over the next few days, I treated mostly minor conditions and slipped into a comfortable routine. There were, however, sharp reminders of where we really were and of the challenges to our survival lurking just outside of, and sometimes within, our camp. One morning, I turned my boots upside down outside my tent and banged them together before I put them on, to be sure nothing had crawled inside during the night. It’s a routine we all followed—except this time something fell out. It was a scorpion—every bit as mean as it looks. The scorpion has a brown crablike body with seven “legs” on each side and an upward-curving tail with a stinger and venom gland at the tip. The front two “legs” are actually claws with which it digs in to hold on while it flails its tail overhead to stab venom into its prey (like
one of my toes, for example). The venom is a nerve poison, which contains digestive enzymes that liquify soft tissues, making them easier to consume. The hard parts are left behind uneaten. The bite is immediately and intensely painful, and the poison can be as deadly as a cobra’s. By the time I got over my surprise, the scorpion had escaped into the underbrush.

Other insects were also becoming too familiar with our camp. A member of the native crew, barefoot and in his underwear, came running to my tent one night, shouting that he had been bitten by a tarantula. It had crawled into his closed tent. We discovered that it had come from a nest of tarantulas living on the underside of the floorboards in our latrine. It was an ideal location for them: well protected, with easy access to all the flies attracted to the pit just below. Big as a fist, a tarantula is covered with black hair and has half-inch fangs—frightening and dangerous but normally not deadly, which is unusual in these parts. The Indian’s leg had a painful swelling, but there was no double puncture wound, which fangs would have made. Instead, tiny hairs were scattered all over the swollen skin. The tarantula hadn’t bitten him, but had felt threatened (the feeling had been mutual) and reacted by rubbing its legs across its abdomen, flicking off hairs like arrows. My patient had been shot with hundreds of tarantula hairs. They were easily removed with duct tape, but the pain and itching promised to last for weeks. The perpetrator had escaped, but its victim took solace in knowing that in the jungle tarantulas often meet horrible ends when they in turn are attacked by wasps. The wasp injects a paralyzing venom and then lays an egg on the tarantula. Alive but helpless, the tarantula becomes a fresh food supply for the hatching wasp. In the Amazon, there is no mercy in the competition for survival.

So far our camp had protected us well enough from the hazards around us, but as a jungle outpost it was becoming more and more isolated. The water level was steadily dropping. Soon it would be impossible to get the canoes out of the lake and onto the river. We might still hike out, but if the canoes couldn’t be floated through the channel, we would be unable to take out much of our supplies, not
to mention all our equipment and specimens. And once we did reach the river, we would have to find other canoes to get us out. Lowering water level or not, it still rained every day. Our clearing had become a sea of mud on which our tents were practically afloat. Kneeling on the tent floor would create an imprint so deep that when I rose up I could hear a sucking noise from below. But this was the Amazon and Antonio said the season had been unusually dry. We would have to leave in a couple of days.

While the biologists hurriedly finished their projects, I continued to run my clinic outside on a mat of heliconia leaves. Antonio often hung out with me when he had free time and I now routinely solicited his advice on patient treatment. One of our group came to me complaining of burning pain when he urinated. He had an ordinary urinary-tract infection, but because we were leaving soon and spirits were high, I thought I’d suggest another diagnosis.

“Were you swimming in the lake today?” I asked.

“Yes, but I wore my underwear,” he said, a little defensively.

“Sometimes that’s not enough,” I said solemnly. “It looks like a candiru is lodged in there.”

He guessed that I was kidding, but I could tell a slight doubt lingered in his mind.

“If we can’t pull it out,” I deadpanned, “the only treatment is to cut the penis off.”

With that the joke was up, but Antonio had actually once mentioned that rather radical treatment to me, and I still wasn’t sure whether he had really meant it. In any case, I had been in the Amazon long enough to know that the best treatment for a urinary infection was gumbolimbo bark, scraped and boiled into a paste. Antonio said he would prepare some for my still somewhat unnerved teammate. I said I would supplement that with a course of antibiotics.

One of my last Amazon patients was an Indian who had hooked a piranha and cut his finger on its razor-sharp teeth. I could have sewn the wound closed, but specimen jars filled with ants were readily available. With our entomologist’s approval, and with his tweezers, I removed a few army ants. Under Antonio’s watchful gaze, I placed four
ants, one by one, head-down over the cut. After they bit into it, I twisted their heads off. The wound closed neatly and Antonio smiled his approval.

Two days later we left the jungle, hiking out because our weight would have sunk the canoes too low into the water. As it was, they were already loaded down with all our specimens, equipment, and supplies. With a lot of machete work to deepen the channel, the Indians managed to float the canoes out, dragging them part of the way.

We met up with the crew at the river, and I said good-bye to Antonio. I admired my teacher, yet I felt sadness for him. A teacher’s influence endures if his students turn into teachers. In the United States, surgical technique is passed down by the principle of “watch one, do one, teach one.” I had watched one; I had even done one. But I was a dead end. Antonio’s wisdom was in imminent danger of extinction because he had precious few people whom he could entrust to carry it on. In fact, Antonio himself was an endangered species. His whole way of life was coming to an end. His people had prevailed in an incredibly hostile environment by learning ways to transform threats to survival into means for survival. Now, suddenly, oil pipelines, logging roads, and airstrips are destroying his habitat, injecting an outside culture that spreads like an infection. Antonio himself is contaminated—by T-shirts, rifles, and gringos who pay cash. Workers, settlers, and scientists on expeditions are introducing strange artifacts and an exotic lifestyle. Antonio and his people can’t cope with that kind of antigen, because it comes from a society, an organism, that until now has been entirely outside their ecosystem. Like a virus the body has never been exposed to, it encounters little resistance and spreads rapidly. Tribes that have learned to protect themselves from headhunters, crocodiles, and poisonous snakes have never been attacked by modern civilization. They have no defense against something that targets not an individual but the entire culture. In harsh surroundings, survival of weak species, such as ants or humans, depends on their members maintaining links to their society. Weaken
those bonds and you threaten the larger organism that keeps them alive.

A society collectively builds a storehouse of knowledge, tribal wisdom, that provides the spiritual and practical rules and tools to compete successfully in an extreme environment. Across generations, group behavior is modified in response to changing conditions, but neither the individual nor his society has the capacity to adapt when the change is sudden, extreme, or unnatural. The injection of an alien culture into the Amazon is all three of those, and it will soon make the Amazon tribes extinct.

But what of the individual Indians? If Antonio’s grandchildren are dispersed into an alien culture, can they retain their “Indian-ness”—the collection of mental and physical adaptations that allow them to survive in the jungle—so that they can be reintroduced into the jungle at some later date, like zoo specimens released into the wild? In a culture without a written language, knowledge is stored only as memory; it only takes a gap of one generation to wipe it out entirely and irrevocably. Children of subsequent generations will have lost the tribal wisdom that was their species most effective adaptation to their environment.

Amazon natives do have at least some survival adaptations built into their bodies. They live there and drink the water, yet rarely get malaria and are at least partially resistant to parasites. These strengths, shaped by natural selection, are an essential part of them that they would carry back to the jungle. But the Indians itch when bitten by mosquitoes, feel pain when stung by conga ants, are not resistant to crocodile bites, and die from snake venom. The Amazon is a tough taskmaster. Most of their survival ability is the result of mental and physical toughness forged into each person as he or she grows up in, and is hardened by, the demands of the surroundings.

The genes you bring into the jungle are less critical for survival than the adaptations you make once you get there. The Amazon provides some surprising examples of an organism’s adaptive response to environmental conditions. Remove a poison-dart frog from the jungle, and its poison will progressively weaken. Put it back, and the poison
becomes strong again. The frog’s offspring, if born in captivity, will lack the ability to produce poison. If put back in the jungle, would they develop the poison their ancestors had? No one knows.

In this respect humans may be analogous to the poison-dart frogs. Someone raised in the jungle will retain his ability to survive there even after being away for some time. If his offspring were born outside the jungle, however, would they still have an innate ability to survive there? Or, as seems more likely, would they be as vulnerable as a brightly colored frog without any poison?

The survival adaptations I saw in the boy on whom I operated flowed from three sources, each endowing him with both physical and mental strength. His society, with its tribal norms and mores, provided practical rules as well as spiritual support. His body, with its generations of genetic adaptations, had evolved to increase his immunity and perhaps also reinforce the brain circuits that facilitate pain endurance and encourage purposeful behavior under stress. His environment, with its relentless supply of abrasive agents, had toughened his body with calluses and muscles, and toughened his will.

The survival instinct is too abstract a concept for people who act on it every day of their lives, as do the Indians of the Amazon. Living so close to the edge, they don’t have the luxury, or the need, to step back and examine its origins. The idea of studying it would seem frivolous, the machines used to do it incomprehensible. Pondering the nature of survival is left to those strangers who fly in and fly out of the only world these survivalists know.

I left the Amazon from a jungle airstrip three canoe-days downriver from Antonio’s village. As I boarded the plane I immediately sensed tension inside. A nun was holding a sheaf of newspapers like a bouquet of flowers, speaking with a strangely flat affect to the person next to her. As I watched, she unwrapped the sheaf to reveal three blood-stained spears. The sight chilled everyone on the plane. She told us the spears were part of a fusillade of eighteen spears used to kill a priest and two nuns who had ventured into the jungle just 17 miles from where I had been. The murders had occurred on the same day Antonio told me about his tribe’s warrior past.

There are still some isolated tribes resisting any contamination of
their way of life, exercising their will to survive by attacking what they perceive to be alien human predators. Though 17 miles is a long way through jungle terrain, even the most isolated tribes cannot hold out for long. The Indians living there are barely aware of “Ecuador,” having no concept of what a country is, but they are surrounded by it on all sides. As terrified as cornered animals, they react violently to threats they cannot understand. They have nowhere else to go. Once their habitat is gone, they will be too. And the rest of us will not even know what we lost.