Meeting with Gurunam, we spent the whole hour going through cane fields and pastures toward the river of water of reddish colour. Then we sit in the motor pie, the sides of which are reinforced with sheathing boards. It’s August (winter in the southern hemisphere), but the air is colder than you would expect from the jungle. Wind el surazo (“South”) blows from the vast pampas to the South. (I later learned that it was this wind that was so cold that fish and pink river dolphins were massively dying all over the Amazon.)
For another hour, we sail on a motor boat on the river past the snow-white big herons (such as those that carefully walk through the swamps of the Bay of Jamaica in new York), and then arrive at the settlement of tsimane Chakal. “Gringolandia, softly says Gurven, when the field of view gets some tents Coleman, his base camp. Tsimane don’t live in tents”.
There is no Central village as such — only a freshly painted school building, located next to the field where men play football every evening. Members of the tsimane tribe live in different places scattered along the river; each family or group of families takes care of the rice, maize and cassava fields. Some tsimane believe that their decentralized way of life helped them resist Spanish influence. The potential colonizers found no authority to be seized, no priests or kings to be drawn to their side. Before the invasion of the Spaniards, which began in the XVII century, the tribe tsimane just went even further into the jungle.
Soon we are walking along a narrow path parallel to the river. When among the undergrowth seemed Polyana, Arnulfo, our guide from among tsimane, gravely emits a small crashing sound. Gurwen also picks up the call. High and stretched like the last sound of an owl’s cry, it serves as a sign of politeness in the jungle, informing the people in front of us of our approach.
When we come to the clearing, Gurven and Arnulfo say greetings in the language of tsimane. A group of boys playing with wolves, carved from hazelnut. The rods are nails hammered into the shells. Children stare at strangers, frown at first, but they have already seen strangers, so quickly resume the game, spinning tops skillful sharp movements. Two women sitting on a large wicker Mat respond to the greeting. The little girl is lying face down on the lap of one of the women, who patiently touches her hair, pulling out lice and nits and biting them with her teeth. We are told that all the men have gone hunting for the whole day. We say goodbye (a bit later Gurven explains, that in tribe not adopted visit have women in the absence of men) and continue its way.
We see fields of corn, many dogs, canoes, exquisite wicker mats, as well as mortars and pistils waist-high and many different tools made of materials available in the jungle. It is this skill among the jungle that most amazes me — a new Yorker of the XXI century, whose brain is drugged by a computer and spoiled by the Internet. Tsimane cut graceful canoes from tree trunks and swim in them along the rivers, starting with long poles. From palm fronds to weave mats and make the roofs of the huts. The settlements of tsimane in the jungle are surrounded by useful trees and plants — papaya, banana and tutuma tree, on which grow large fruits similar to pumpkin (members of the tribe make bowls out of them). Locals use ginger root to treat insect bites. They sleep on raised platforms. As Gurwen explains, here the value of each person is determined not by his property, but by his skill in extracting resources from the jungle. “Yes, you can lose everything, but then you just build a new house, fish, hunt. Almost everyone can do it, — he says. — In a sense, this is freedom.”
I could go on and on about the amazing life of the qimane tribe, but I’m actually here to observe what I can’t see directly: the hidden microbial and parasitological landscape. I want to know what a place looks like where the immune system doesn’t fail. The answer is: it looks alive.
Much to the chagrin of Gurven, members of the tribe tsimane often collect drinking water from a dirty river, where, in all probability, is full of bacteria. Pigs, chickens, dogs and sometimes domestic spider monkeys roam freely around. Each of them brings its own unique mixture of microbes to the environment. The women of the tsimane tribe make a Hoppy drink by chewing and spitting boiled cassava, then leave it to ferment. In other words, they regularly consume what the regular new York organic store offers as “live crops.” And, of course, in the intestine of most tsimane live krivohlavy.
In General, tsimane live in an environment that scientists call “living” environment. But is it important? Numerous data suggest that such a habitat protects people from autoimmune and allergic diseases for one simple reason: in the process of evolution, the immune system was formed, designed specifically for such an environment. Therefore, if the immune system is not subjected to the intense stimulation present in such an environment, it is unbalanced.
Of course, life in such a place is not easy. The infant mortality rate, which decreased slightly after vaccination in the 1990s, remains high . One in five children does not live to be five years old. By the age of 15, another 5% of children die from diseases. In fact, a quarter of all children born do not live to puberty — and this figure is now better than in the early twentieth century. (On the other hand, every fifth member of the tsimane tribe lives to be sixty; this is one of the main conclusions of Gurven, in a sense contrary to common sense.) Nevertheless, despite the widespread spread of infectious and parasitic diseases, tsimane do not look either sick or exhausted. Many of them are missing a few front teeth (according to Gurven, this is the result of addiction to sugar cane and citrus), but otherwise they seem strong and healthy.
On the way back we will take a motor boat down the river and then drive through the reed fields and muddy dirt roads. To return home, I will fly a small plane from the town of San Borja over the majestic wall of the Andes to the West, make a transfer to the capital of La Paz, located at an altitude of more than 3,600 meters above sea level, and then go to new York via Miami by jet.
This journey takes place in full accordance with a well-defined gradient of allergic diseases. I will move from an area where allergic diseases do not exist (where the jungle is a source of livelihood), to an area with a slightly higher level of allergic diseases (a Bolivian city where people live without excesses), then to an area with an even higher concentration of allergic diseases (a large city in a developing country) and finally to where allergies are most common (a large city in a developed country).
The gradient described above also takes place in time. By tracing your ancestry back several generations, you will likely find that the incidence of hay fever and asthma decreases in each previous generation. For example, you (like me) may have asthma and food allergies. Meanwhile, your parents may have only had seasonal hay fever.  However, only a few of our grandparents (or great-grandparents, as the case may be) suffered from sneezing or difficulty breathing of any kind. In all likelihood, this pattern is not due to the emergence of new factors, and the elimination of the former — the very factors that are still subject to members of the tribe tsimane.
Repeated observations of this kind, supported by a large amount of experimental data (indicating that the immune system reacts differently depending on the history of exposure to certain factors), have led some immunologists to question the basic assumptions underlying their field of activity. Our understanding of the immune system is based on work that was carried out mainly in the twentieth century, but by that time we were living in completely new conditions from an evolutionary point of view. In other words, we may have made the mistake of studying and systematizing data about an ecosystem that seemed exotic, only to discover that we are not really in the jungle, but in the Bronx zoo.
William Parker, an immunologist at Duke University, says: “In our time, we immunologists have come to the alarming realization that the immune system, on which we have spent all our energy and energy… over the past fifty years, as it turned out, is significantly different from the system formed in the process of natural selection”.
This brings us closer to the point.