The Problem

The ayahuasca drink is made from the stem of the ayahuasca vine, Banisteriopsis caapi. Sometimes, but rarely, the drink is made from the ayahuasca vine alone; almost invariably other plants are added. These additional ingredients are most often the leaves of any of three compañeros, companion plants—the shrub chacruna, Psychotria viridis; the closely related shrub sameruca, Psychotria carthaginensis; and a vine variously called ocoyagé, chalipanga, chagraponga, and huambisa, Diplopterys cabrerana.

Snuffing yopo

It is in fact the companion plant that contains the potent hallucinogen dimethyltryptamine. But DMT, when taken orally, is inactivated by peripheral monoamine oxidase-A, an enzyme found in the lining of the stomach, whose function is precisely to oxidize molecules containing an NH2 amine group, such as DMT.

There are thus two ways to ingest DMT or plants containing DMT. The first is by parenteral ingestion—using a route other than the digestive tract, such as smoking, injection, or inhalation—which bypasses the MAO in the stomach lining. For example, a number of indigenous peoples around the Orinoco Basin in Venezuela inhale a snuff called epená, made from the resinous fluid in the inner bark of several trees in the genus Virola that contain large amounts of DMT (Schultes 1954; Seit, 1967; Schultes & Swain, 1976). Similarly, the Guahibo Indians of the Orinoco Basin use a snuff called yopo—also called cohoba, vilca, and huilca—made from the DMT-rich beans of the plant Anadenanthera peregrina (De Budowski, Marini-Bettòlo, Delle Monache, & Ferrari, 1974; Mckenna & Towers, 1985; Ott, 1996, p. 164-165).

Drinking ayahuasca

But it is also possible to mix the DMT with an MAO inhibitor that prevents the breakdown of DMT in the digestive tract. And that is just what the ayahuasca vine contains—the beta-carbolines harmine, harmaline, and tetrahydroharmine, which are potent inhibitors of MAO-A. Combining the ingredients of the ayahuasca drink allows the DMT to produce its hallucinogenic effect when ingested orally—a unique solution that apparently developed only in the Upper Amazon. The gastrointestinal effects of the beta-carboline MAO inhibitors additionally make the ayahuasca drink a powerful emetic and purgative.

These facts raise two highly controverted and interconnected puzzles. How in the world did indigenous peoples in the Upper Amazon come up with the idea of combining DMT with an MAO inhibitor? And when and where did they first do it?

I have the answer to these questions. We do not know.

Popular Estimates

Writers on ayahuasca have often proposed that the use of the drink is very ancient; the date of about 5000 years BP recurs frequently. Anthropologists Ana María Llamazares and Carlos Martínez Sarasola (2004), for example, write that the use of ayahuasca “is so deep-rooted in the native philosophy and mythology that there is no doubt about its great antiquity, as a part of aboriginal life. Archaeological finds in Ecuador show that the indigenous Amazons have been using it for about 5000 years.” Anthropologist Jeremy Narby (1998, p. 154) states that ayahuasca “belongs to the indigenous people of Western Amazonia, who hold the keys to a way of knowing that they have practiced without interruption for at least five thousand years.” Anthropologist Peter Furst (1976; p. 45-46) says that “we are probably not far wrong in suggesting that [the ayahuasca drink] is at least as old … as 3000 BC or even before.”

The claim that the ayahuasca drink has been used for 5000 years has become formulaic. A quick search of ayahuasca tourist and related websites reveals virtually identical statements of this claim: “The use of Ayahuasca has been recorded over 5000 years ago by the natives of Amazon and surrounding areas,” “Ayahuasca has been known to people for over 5000 years,” “This plant medicine has been used for over 5000 years throughout the Amazonian basin,” “Ayahuasca has been used for over 5000 years.” These examples could be multiplied.

And this claim is, in fact, remarkable. Just for perspective, the date of 3000 BC would make the origins of the ayahuasca drink as old as the founding of the first Egyptian dynasty, five centuries older than the reign of the Sumerian king Gilgamesh, and almost ten centuries older than the earliest South American devices yet discovered for the ingestion of DMT-containing plants—two pipes found in association with Anadenanthera seeds in northwest Argentina, which have been radiocarbon dated to 2130 BC, and which had residues that tested positive for DMT (Torres, 1995, p. 312-314).

And while it is true that the parenteral ingestion of DMT-containing plants is of considerable antiquity in South America, there is no corresponding archeological or documentary evidence prior to the eighteenth century for the combination of a DMT-containing plant with the ayahuasca vine for oral ingestion.

But first: Why such extraordinary claims for which support is so thin? I think there are two reasons. The first is that, in an attempt to legitimate ayahuasca use, its proponents invoke the culturally resonant trope of a millennia-old indigenous wisdom. The second is the odd affectation of European colonialism that indigenous people are without history—that, unlike Europeans, they are unchanging in their isolation and innocence. It then follows that the practices of present-day indigenous peoples must reproduce the practices of thousands of years ago. Both reasons, I believe, malign the creativity, adaptability, and ingenuity of indigenous cultures.

The Use of DMT-Containing Snuffs

Chavín decorated mortar

Archeological evidence—ranging from the discovery of distinctive snuffing devices to the identification of plant residues in snuffing kits—points to a long history of indigenous South American peoples parenterally ingesting DMT-containing plants by both snuffing and smoking (for an excellent survey, see Torres, 1995; see also Wassén, 1967). As we noted above, such inhaled DMT is unaffected by the MAO-A in the gastric tract, and thus acts as a hallucinogen without the addition of the ayahuasca vine—and thus too without the gastrointestinal effects of the ayahuasca beta-carbolines.

The Heart of Chavín

The earliest known snuffing devices in South America come from central coastal Peru—whale-bone snuff trays and bird-bone tubes, dated to approximately 1200 BC (Torres, 1995, p. 298-299, 320). The use of snuffed DMT-containing plants later became—along with the use of the San Pedro cactus—a central feature of the Chavín culture, which occupied the northern Andean highlands of Peru, about halfway between the tropical forests and coastal plains, from approximately 900 to 200 BC.

Chavín head with fangs, wide-open eyes, and nasal mucus

Elaborately carved mortars, presumably used to grind Anadenanthera beans, have been uncovered (Burger, 1995, ill. 217), as well as bone tubes (ill. 96), decorated spoons (ill. 219), and elaborately carved snuff trays (ills. 85, 86), although I am not aware of any chemical analysis of residues on these snuffing devices.

Particularly striking is artwork at Chavín de Huantar that shows figures with wide-open eyes and streams of mucus running from their nostrils, presumably as a result of snuffing; some of these heads appear to be half human and half feline or half bird (ill. 144; see generally p. 157-159; Torres, 1995, p. 301), perhaps depicting a form of shamanic transformation (Cordy-Collins, 1977).

Precious Heirlooms

Snuffing bowl from Carriacou

Of similar antiquity are three ceramic snuffing bowls found on the island of Carriacou, near Grenada in the Antilles. These Caribbean islands were colonized from South America about 400 AD. In a study headed by Scott Fitzpatrick of North Carolina State University (Fitzpatrick, Kaye, Feathers, Pavia, & Marsaglia, 2009; see also Braun, 2008), petrographic analysis of the mineral content of the bowls indicated that they were not made using local materials, and thus were probably not manufactured on Carriacou, but rather imported from elsewhere. Moreover, a type of radioactive isotope analysis called luminescence dating placed the three snuffing bowls roughly between 400 and 100 BC—that is, somewhere between five and eight centuries before they were carried to the islands by migrants from South America.

Alas, no chemical analysis was done to determine what substance had been used in the recovered snuffing bowls; and, of course, we have no idea under what circumstances the snuffing bowls were used. But clearly they were important enough to be preserved, passed on for centuries, and carried by boat from South America to the Caribbean.

The Tiwanaku Conundrum

Much later in time, the site of Tiwanaku, recognized by Andean scholars as one of the most important precursors to the Inca Empire, flourished as the ritual and administrative capital of a major state power approximately between 700 and 1100 AD. Here too we find clear evidence of the use of an Anadenanthera snuff, although the circumstances of this use, whether shamanic or recreational, remain unclear.

Snuffing kit from Tiwanaku

Tiwanaku culture produced a variety of small carved objects that included puma and jaguar effigies, incense burners, and highly decorated snuffing tablets and tubes. Many mummies and skeletons from this culture were buried with such tablets and snuffing kits. One archaeologist reported recovering 614 snuffing kits from a single excavation (Ogalde, Arriaza, & Soto, 2009).

Here we do have chemical analyses of samples of archeological snuff powders from such kits, which indicate the presence of bufotenine, DMT, and 5-MeO-DMT. The presence of bufotenine suggests that the source of the powder was any of several DMT-rich plants in the genus Anadenanthera; small pouches containing Anadenanthera seeds have also been found in several burials. CAT scans of Tiwanakuan skulls have shown signs of chronic perinasal damage in some cases, likely caused by frequent snuffing of Anadenanthera (Torres, Repke, Chan, McKenna, Llagostera, & Schultes, 1991; Torres 1996).

Many psychoactive alkaloids accumulate in hair and other body tissues. Chemical archaeologist Juan Pablo Ogalde and his colleagues at the University of Tarapacá in Arica, Chile, analyzed the chemical composition of hairs from 32 mummies from northern Chile, dating to the Tiwanakuan expansion, looking specifically for harmine and 5-MeO-DMT (Ogalde, Arriaza, & Soto, 2009). But the results of the hair tests were surprising. None of the 32 mummy hair samples tested positive for 5-MeO-DMT, and two tested positive for harmine.

Stone snuff tray from Tiwanaku

These results certainly appear to be inconsistent with the results of the testing of snuff powders from archeological snuff kits at other Tiwanaku sites, which tested positive for 5-MeO-DMT as well as for bufotenine and DMT. However, as Trout (2008) points out, the absence of 5-MeO-DMT from the hair samples is difficult to evaluate, given our current ignorance of whether this tryptamine is detectable in hair at all.

Most interest, however, has centered on the reported presence of harmine. One of the two samples testing positive for harmine came from an adult male, who had a snuffing tablet in his grave, and a sclerotic process in the perinasal area; but the other was from a one-year-old infant, also buried with a snuffing tablet.

Why is there harmine in the hair of an adult male and a one-year-old infant? The hypothesis embraced by the authors of the study is that the likely source for the harmine in these two samples was the ayahuasca vine, which must have been imported, over some distance and rough terrain, from the Upper Amazon. The absence of 5-MeO-DMT in the hair samples would then indicate that the ayahuasca vine was consumed without the addition of a DMT-containing companion plant.

Stone figure from Tiwanaku holding two snuff tablets

But if the ayahuasca vine could have been imported over an apparently extensive trading network, then such companion plants would also have been available, and presumably would have been imported along with the vine if the ayahuasca drink was in fact being used at that time. One possibility is that the Tiwanakuans consumed the ayahuasca vine by itself medicinally for its emetic and purgative properties, or, without a companion plant, for its independent visionary effects.

Another possibility is that here we see the roots of the practice of combining the ayahuasca vine with a DMT-containing plant; even when the DMT-containing plant is ingested parenterally, the MAO inhibition provided by the ayahuasca vine can reportedly potentiate the visionary effect (Trout, 2008). So perhaps the Tiwanakuans, like the Guahibo today, combined sniffing Anadenanthera with chewing the ayahuasca vine (Torres & Repko, 2006, p. 73); or, like the Piaroa today, pounded shoots of the ayahuasca vine into a paste along with Anadenanthera seeds (Rodd, 2002). Given this finding of harmine, therefore, anthropologist Luis Eduardo Luna found it “unlikely that the use of Banisteriopsis caapi, perhaps also with some additives, is only a recent phenomenon” (2011, p. 125).

But we must bear in mind that other sources for the harmine are also possible—tobacco smoke, for example, or well-cooked food, or a number of plant species (Jiménez, Riverón-Negrete, Abdullaev, Espinosa-Aguirre, & Rodríguez-Arnaiz, 2008; Janiger & Dobkin de Rios, 1973), including snuffs made from some species of Virola (Agurell, Holmstedt, Lindgren,& Schultes, 1969; McKenna, Abbot, & Towers, 1984; Lindgren, 1995, p. 347); or, as the authors of the study note, at least some forms of hair dye (Ogalde, Arriaza, & Soto, 2009, p. 470).

The Ayahuasca Drink

As opposed to the snuffing of DMT-containing plants, there is no archeological evidence for the combination of a DMT-containing plant with the ayahuasca vine for oral ingestion—that is, for the use of an ayahuasca drink. This may in part be an artifact of the way ayahuasca is consumed—from bowls or cups, just like any other drink. As anthropologist and ethnobotanist Constantino Torres (1995, p. 293-294) notes, the ayahuasca drink does not require any specific paraphernalia for its ingestion—unlike, say, the distinctive tablets and hollow tubes used for snuffing, or the pipes used for smoking, often made of materials that do not decay, and preserved in places, such as graves, where we can discover them.

The Quito Bowl

The Quito Bowl

Every claim of great antiquity for the ayahuasca drink—for example, the 5000-year claims by Narby (1998, p. 164) or Llamazres and Martínez Sarasola (2004)—ultimately seeks its support in a single article by archeologist Plutarco Naranjo (1986). But, as anthropologist and musicologist Bernd Brabec de Mori (2011, p. 24) points out, the article shows only that people in the Ecuadorian rainforests began producing small ceramic vessels about 2400 BC. Without chemical analysis of any residue in these cups, and without having independently established the use of ayahuasca in that culture, little can be inferred from the cups themselves.

One often-cited specifically ayahuasca-related archeological artifact is a decorated stone bowl preserved in the museum in Quito, Ecuador, which was first described, and connected with ayahuasca use, by Naranjo in 1983. The following is, as far as I can tell, Naranjo’s entire statement about this bowl:

El objeto mas antiguo que conocemos, con toda probabilidad, relacionado con el uso del ayahuasca, es una copa ceremonial, tallada en piedra, con ornamentación incisa, la misma que ha sido encontrada en el área de la cultura Pastaza (Ecuador amazónico) y que forma parte de las collecciones del Museo Etnológico de la Universidad Central. La mencionada cultura corresponde al períodico que va de 500 años A.C. a 500 años P.C. (Fig 28 y 29).

Figures 28 and 29 are very blurry black-and-white photographs of a decorated bowl. Other than the carved figures, however, we are once again given no reason to believe that the cup ever contained ayahuasca or any of the constituents of the ayahuasca drink, or even that the use of ayahuasca was a feature of this culture.

In fact, it seems that Naranjo later moderated this claim; in a 1995 article, he writes:

Another psychedelic plant with widespread use in the Amazon basin is ayahuasca or caapi, known as Banisteriopsis caapi. Due to the trans-Andean trade between the coast and the Amazon region of present-day Ecuador, first coca and later ayahuasca reached the coast…. In ceramics of the Milagro-Quevedo culture (500 BC to 500 AD), certain ceremonial vessels appeared, richly adorned with zoomorphic and anthropomorphic figures (Figure 5). Known today as vasos de brujo or cocinas de brujo, these containers must have been used to cook or boil psychotropic plants.

The cited Figure 5 appears to be a much clearer version of Figure 28 in the earlier work. The figure caption reads:

Figure 5. A vaso or cocina de brujo. This ceramic container of the Milagro-Quevedo culture (500 BC to 500 AD) perhaps served as a collective vessel so that each participating member of the ceremony could drink part of the liquid.

It is hard to know what this bowl is in fact able to prove. The proposed dates for the bowl span a thousand years. The vessel is decorated with what may—or may not be—mythological figures, and that apparently is all we really know. To claim, in the absence of other evidence, that it must have held a psychoactive substance of any kind is purely speculative. As Torres (1995, p. 294) puts it, pointedly: “The verification of these practices solely on the basis of elaborate drinking vessels is practically impossible.”

Loud Silences

Apart from this stone bowl and the ceramic Ecuadorian cups, little substantive evidence has been offered for any early use of ayahuasca. What is striking, in fact, is the silence about the ayahuasca drink from those observers we might most expect to have taken notice of it.

For example, by the late 1400s the Inca Empire, under the Supreme Inca Pachacuti, had reached Ecuador, and presumably would have encountered the ayahuasca drink had it been in use there. The Incas had acute observational skills and a keen interest in plants, their growing conditions, and their local uses—not only the new species they encountered, but all the local varieties of familiar cultivated plants, and were devoted to creating the ideal cultivar of each plant for every microclimate in their empire. Yet there is no Inca material that shows familiarity with anything like either the ayahuasca vine or the ayahuasca drink, and there is no sign of ayahuasca use or the memory of its use among highland Indians.

In the same way, Europeans had begun to explore the Amazon as early as 1541, and the ritual use of psychoactive snuffs was known to the Spaniards from the early days of their arrival in the New World. Along with the conquistadors there came chroniclers and explorers, often curious about the nature and practical uses of New World plants. For example, the Spanish chronicler Polo de Ondegardo, writing in 1571, records the use of vilca by what he called sorcerers, hechiceros; in 1582, the Relaciones Geográficas de la Provincia De Xauxa describes vilca as a bean used in conjunction with tobacco snuff (Torres, 1995, p. 297; Torres & Repke, 2006, p. 26). There are no corresponding descriptions of the use of either the ayahuasca vine or drink.

Similarly, sixteenth- and seventeenth-century Spanish missionary priests wrote vivid and horrified descriptions of the effects of snuffed DMT-containing Anadenanthera, as well as the snuffing and drinking of tobacco, but no similar accounts of ayahuasca. Written descriptions of ayahuasca use do not appear until the eighteenth century, apparently first by the Jesuit Pablo Maroni, published in 1737, and then by the Jesuit Franz Xavier Veigl, published in 1768, who writes of “the so-called ayahuasca, which is a bitter reed, or more specifically, a liana. It serves for mystification and bewitchment” (Brabec de Mori, 2011, p. 32).

Nineteenth-century eyewitness accounts of Shipibo healing ceremonies at the Sarayacu mission similarly describe ceremonies similar to those performed today, including the use of tobacco and piripiri (on which see Taylor, 2006), but with no mention of ayahuasca; only one account refers to “a lethargy produced by a narcotic,” not otherwise identified (Tournon, 2002, p. 70, 80, cited in Brabec de Mori, 2011, p. 33).

The first ethnobotanical account of ayahuasca dates from 1851, although not published until 1873, when the English botanist Richard Spruce encountered the vine among the Tukano of the Rio Uapes in Brazil, who called it caapi. Two years later, Spruce again encountered the same vine in use among the Guahibo on the upper Orinoco, and, in 1857, among the Záparo in the area of the Pastaza river on the border of Ecuador and Peru, who cultivated the vine and from whom he first learned the name ayahuasca (Riba, 2003, p. 3-4).

Putting all of this together, it becomes a plausible hypothesis that the ayahuasca drink—the combination of the ayahuasca vine with a DMT-containing companion plant—originated, not 5000 years ago, but rather much more recently, perhaps in the seventeenth century. There is certainly considerable evidence for the much earlier use of DMT-containing plants by snuffing, and perhaps some small evidence as well for the use of the ayahuasca vine by itself, perhaps without companion plants, either for its emetic and purgative properties or perhaps for its own independent visionary effects, along with other sacred plants such as tobacco, the San Pedro cactus, and perhaps any of several Brugmansia species. But, before the eighteenth century, with regard to the ayahuasca drink, there is silence.

The Argument from Music

Perhaps it can be argued that the use of ayahuasca passed unremarked by waves of conquering and missionizing invaders because it was used secretly in the deep and inaccessible forest. Apart from the fact that this assertion, too, is without evidence of its own, anthropologist Peter Gow (1996) and ethnomusicologist Bernd Brabec de Mori (2011) offer several affirmative arguments concerning the likely time depth of ayahuasca use.

One argument made by Brabec de Mori (2011, p. 35-42) is based on his ethnomusicological study of the ikaro, the song used in ayahuasca healing rituals. What is striking about these songs, he writes, is how similar they all are musically and structurally, even across cultures, while there are significant musicological differences among all other categories of indigenous song. In a recent article, he examined seven samples of these songs, and concluded that the examples “constitute sufficient musical evidence that the song structure called ikaro is truly recognizable between the Napo and Urubamba rivers” (p. 42).

This shared structure, he argues, is consistent with a relatively recent common origin, rather than with a history of thousands of years (p. 36-37):

The musical structure of ikaro is the only song structure compellingly similar between the Río Napo and the Río Urubamba… If ayahuasca would be in use for centuries or even millennia among the mentioned groups, as it is often assumed,… it would appear rather illogical that especially the music connected to ayahuasca sessions would be the only music fairly similar among all the groups…. The only reasonable explanation for this phenomenon is that this music is rather new and was distributed among these groups from the same source.

The Argument from Quechua

A similar argument has been made from the singular importance and prestige of the northern Quechua language in contemporary ayahuasca shamanism. This argument connects the initial spread of ayahuasca specifically to the missionary camps or reducciones that were established in the Upper Amazon by Jesuit missionaries—for example, in Maynas, the old name for the northern Amazonian area in Peru and Ecuador, beginning in 1636 (Gow, 1996, p. 106; Brabec de Mori, 2011, p. 32).

Indigenous people sought the protection of these camps from epidemic disease, depopulation, slave raiders, and the military threats of their neighbors (Gow, 1996, p. 106). Here they were forced to live in common compounds regardless of their tribal distinctions. The intention was that in this way the indios infieles could be more easily controlled and converted to indios cristianos; but the unintended consequence was to form a pressure cooker of cultural interchange.

The common intertribal language in these camps was the linguistically distinct northern Amazonian Quechua, the regional trade language of the area and the mission lingua franca (Gow, 1996, p. 106-107; Brabec de Mori, 2011, p. 32). The fact that northern Quechua is the primary language of ayahuasca shamanism, Gow claims, argues for a relatively recent common origin and a spread through intertribal contact precisely at the Jesuit reducciones.

Ayahuasca shamanism shares a significant Quechua vocabulary across tribal lines. In addition to their own terms, all ayahuasca-using groups also share the Quechua term ayahuasca, even in discourse and songs in their own language (Brabec de Mori, 2011, p. 34). Such terms as llausa, yachay, mariri, supay, shitana, manchari, arkana, and banku—and, of course, icaro—are known and used throughout the Peruvian lowlands, even in discourses and songs in non-Quechua languages (Brabec de Mori, 2011, p. 36-37).

Among the Shipibo, Brabec de Mori points out, all songs are sung in the Shipibo language, with one exception—the ikaros, the songs used at ayahuasca sessions, the one song category that does not sound like other Shipibo songs, and the only songs that are sung in Quechua, or in vocables that, while not Quechua, are intended to sound like Quechua (Brabec de Mori, 2011, p. 36; Saéz, 2011, p. 140; Roe, 1982, p. 89). In the same way, mestizo shaman Agustin Rivas would himself create the melodies of his songs; but so important was Quechua to his icaros that he would have their lyrics written by Faustino Espinosa, an expert on the Quechua language (Bear, 2000, pp. 133, 184).

And it is important to be clear that the Quechua terminology and song lyrics are all from contemporary northern Quechua, not archaic terms preserved from some 5000-year-old ancient or proto-Quechua, without any of the language changes that would be expected to have occurred over the course of millennia.

This origin in the Jesuit reducciones is also consistent, both Gow and Brabec de Mori argue, with the numerous and widespread Catholic features found in ayahuasca ceremonies among otherwise disparate indigenous and mestizo peoples—the way, for example, the shaman blows tobacco smoke over the cup of ayahuasca before it is given to each participant (Gow, 1996, p. 107), or the way the shaman blows tobacco smoke or perfume over the head, body, and—often folded—hands of each participant (Brabec de Mori, 2011, p. 28).

Finally, the claim of vast antiquity for the use of ayahuasca is inconsistent with the number of Amazonian indigenous people who report that they have come in contact with the ayahuasca drink only recently and often within living memory—the Amuesha (Santos-Granero, 1991), the Arakmbut (Gray, 1996), the Cashibo (Frank, 1994, p. 181), the Ese Eja (Alexiades, 2000), the Guarani (Langdon & Santana de Rose, 2012), the Kukama (Rivas, quoted in Brabec de Mori, 2011, p. 46 n. 22), the Kulina (Pollock, 2004), the Matsigenka (Shepard, 1998; 2005, p. 201-203).

The Kulina report having learned the use of ayahuasca from the Kanamari, who in turn got it from the Kaxinawá (Saéz, 2011, p. 141; Lorrain, 1994, p. 132). And there is reason to believe that the Kaxinawá, when their language was studied by Capistrano de Abreu at the beginning of the twentieth century, were not yet using ayahuasca themselves (Saéz, 2011, p. 143; Capistrano de Abreu, 2941, p. 172-175). It would be peculiar for there to be such latecomers to a tradition that was already fifty centuries old.

What is important about these arguments is that they allow us to infer a process of dynamic, innovative, and creative cultural interchange and adaptation over a relatively wide area over a period of perhaps hundreds of years. What they argue against is any idea that ayahuasca use has been widespread and static for fifty centuries.

Point of Origin

We come to the second part of our first question: Where did ayahuasca come from? Again the answer is: We do not know.

The rivers of the Upper Amazon

First, some geography. The Amazon river is formed, at a point about sixty miles southwest of Iquitos, by the confluence of two other great rivers—the Marañón flowing first north and then east, and the Ucayali flowing north. The Napo, running south from Ecuador, joins the newly formed Amazon at Iquitos. The Ucayali in turn is formed further south by the confluence of the Apurímac and Urubamba rivers. The Huallaga runs to the west of, more or less parallel to, and in the same direction as the Ucayali river, and joins the Marañón before the latter reaches the Ucayali to form the Amazon.

The Napo river basin, lying north of Iquitos, connects to the Andean highlands through the accessible Papallacta pass—presumably an ancient trade route, the name papallacta meaning “potato town.” The Napo river in turn connects to the immense thoroughfare of the Amazon river and its tributaries to the south. There is every reason to believe that the area was a significant corridor of both trading and cultural exchange, using northern Quechua as a common language (G. Highpine, personal communication, May 19, 2012).

Brabec de Mori (2011, p. 24, 42), in his densely argued text, reports a scholarly consensus that the original homeland of the ayahuasca vine and its related shamanic practice was precisely north of the Amazon in the valley of the Napo river, and that both the vine and the practice spread, over the course of several centuries, southward along the great river valleys, and from there eastward into Madre de Díos and beyond. That expansion is continuing today. Here are the arguments.

Wild Vines

Slash-and-burn garden

The Amazon rainforest is a mosaic of micro-ecosystems made up of species that are endemic to a very limited area. There are virtually no plant species in the Amazon that are widespread without having been spread by humans (Highpine, 2010a,b,c,d). When a slash-and-burn garden is cleared, the seedlings of useful trees are often spared and protected, to be utilized when the garden is left fallow. When the garden is abandoned to become new-growth jungle, the fallow area is planted with useful successor species, such as fruit trees intended to attract frugivore game animals (Beyer, 2010, p. 303-305).

The ayahuasca vine (Banisteriopsis caapi)

In particular, the ayahuasca vine requires sunlight when young, and so is planted in fallow gardens, where it will get a head start in the sun before it becomes part of the forest. Ayahuasca vines that appear to be wild in fact often grow close to villages in such fallow gardens; and others are feral, where the people who originally planted them have moved away or died out (Highpine, 2010a,b,c,d).

Zuluaga (2004, p. 132), an expert on traditional Colombian medicine, claims that it is precisely in the western Amazonian lowlands around the Napo river where the ayahuasca vine can still be found in its wild form; elsewhere, he says, the vine is found only in cultivated form, grown from seeds carried by indigenous people and exchanged in trade. The claim, however, is difficult to evaluate. Zuluaga offers no references and no indication of the morphological or other criteria by which he or his informants distinguish wild from cultivated or feral vines.

Prestige Quechua

In addition, the Napo river region is precisely the area where northern Amazonian Quechua—which provided the prestige language and technical vocabulary for ayahuasca shamanism and its ikaros—has traditionally been spoken (Brabec de Mori, 2011, p. 43; Highpine, 2008). It was in just this area that Richard Spruce, in 1857, first heard the word ayahuasca (Riba, 2003, p. 4).

Even today, it is the north that is seen as the homeland of ayahuasca teachings. As part of his musicological research, Brabec de Mori (2011, p. 30-31, Fig. 2) traced the movements of contemporary ayahuasqueros of various ethnic origins along the Ucayali, and found that they either traveled south from their birthplace to teach ayahuasca shamanism, or north from their residence to study it (p. 30-31, Fig. 2).

I have never heard of any renowned ayahuasqueros on the Ucayali river who had been instructed by someone upriver, say, from the south, or from more remote areas. A survey of recent migrations of ayahuasqueros in the Ucayali valley reveals that almost without exception, the teachers came from downriver, and the students traveled toward the bigger settlements to meet them. After having learned how to use ayahuasca, the students traveled upriver again, or returned to more remote places where they carry out their practice.

In the same way, the Piro and Campa in the even more remote Lower Urubamba do not “see any continuity of knowledge between contemporary practice and their ancestral traditions” (Gow, 1996, p. 96). Rather, they—like the ayahuasqueros of the Ucayali interviewed by Brabec de Mori—look downriver for the source of shamanic power, to the shamans of the lower Ucayali and the Amazon river.

Prototype Shamanism

This reported consensus is based in part, I think, on a highly subjective sense that the ayahuasca shamanism of the Napo river valley is in some way prototypical. As early as 1858, the Ecuadorian geographer Manuel Villavicencio described the uses of ayahuasca by several indigenous peoples of the Napo region as follows:

To foresee and to answer accurately in difficult cases, be it to reply opportunely to ambassadors from other tribes in a question of war; to decipher plans of the enemy through the medium of this magic drink and take proper steps for attack and defense; to ascertain, when a relative is sick, what sorcerer has put on the hex; to carry out a friendly visit to other tribes; to welcome foreign travelers; or, at least, to make sure of the love of their womenfolk

—which is exactly the core of the way the ayahuasca drink is used throughout its current extent in the Upper Amazon, at least until ayahuasca was reconceptualized and repurposed by foreign tourists beginning in about 1995.

Taita Casimiro Mamallacta, Napo Runa shaman (photo by Gayle Highpine)

Moreover, the Napo Runa, the indigenous people of the region, are reputed to be in particularly close relationship with the plants. According to Gayle Highpine (2008), who studied traditional Amazonian agriculture in the Napo valley, the Napo Runa “are famous among anthropologists and recognized by other Indians for the exceptionally large number of different medicinal plants that they know,” with nearly 1600 plants documented with active medicinal use. Napo Runa women address medicinal plants in song as if they were lovers, manioc plants as if they were children. In ritual contexts the name of a plant species is often followed by the Quechua term runa, man, or warmi, woman. Plants are considered supai, spirits—frightening, deceptive, dangerous, attractive, and sources of life (Swanson, 2009, p. 37-38).

And the Napo Runa are reputed as well to have a particularly close relationship to the ayahuasca vine. Oral tradition, especially in Colombia, holds that ayahuasca comes originally from the Napo river (Highpine, 2008). Highpine reports (2009) that their ayahuasca drink, as compared with that made by other indigenous and mestizo people, uses a much higher proportion of the vine and relatively less of the companion plant—“as much vine as possible,” she writes, “as much fresh vine as can be crammed into a cooking pot.”

Pathways of Expansion

The Napo River

If the Napo river valley is the home of ayahuasca, then how did it spread? Travel and exchange have occurred throughout this since long before the arrival of Europeans. Cultural exchange has been facilitated by trade, by rules of linguistic exogamy, and by itinerant herbalists collecting and selling medicinal plants from the Pacific coast to the lowland jungle. What seems to the unfamiliar eye to be a vast undifferentiated landscape is in fact threaded with riverine highways navigable over long distances in dugout canoes.

And shamans have always been nodes in this interethnic network of social relations—caring for each other’s patients, training each other’s apprentices, and exchanging visions, songs, knowledge, and power objects, such as stones or feather crowns. Forcing indigenous people to live together in missionary reducciones simply accelerated the process, bringing together shamans from different tribes to share their practices and discoveries (Beyer, 2010, p. 282).

Brabec de Mori (2011, p. 31-32) proposes that ayahuasca-using groups fall into three categories—those who consider their own practice to be traditional and of long standing; those among whom there can be heard at least some stories about an introduction of ayahuasca from neighboring groups; and those who report that they have come into contact with ayahuasca only much more recently. These three groups, he says, have distinct geographic distributions. The first tend to be found to be among the indigenous and mestizo populations of the Peruvian north or along the big rivers in the south—the Marañon, Huallaga, and Ucayali; the second tend to be further away from the Napo river, in Madre de Díos, for example; and the third are those who have, until recently, been most isolated and remote. Such a distribution would then represent the historical spread of the ayahuasca drink—a diffusion that continues to this day.

Now all of this needs to be taken with considerable caution. The Upper Amazon is very large, its history and prehistory are complex, and the movement of peoples within it has been little studied. Epidemics, warfare, slavery, the rubber boom, and successive waves of Jesuit, Franciscan, and Capuchin missionaries have dramatically changed the indigenous landscape, many earlier groups have disappeared, others have had their populations decimated, some have migrated to other regions, and cultural exchanges have occurred that have not been well identified (Zuluaga, 2004, p. 130).

In fact, it is often difficult to decide whether two neighboring communities with similar customs and similar tongues constitute one ethnic group or two. Amazonian peoples typically identify with much smaller groups, such as their own village; the idea of ethnic identity is a relatively new and modern one (Highpine, 2008). As Brabec de Mori himself states (2011, p. 29), “the ethnohistory of western Amazonia is very complicated and poorly documented… reliable ethnohistorical comparative data is relatively rare.”

Combining the Plants

Now we come to the second puzzle: How in the world did indigenous peoples in the Upper Amazon come up with the idea of combining DMT with an MAO inhibitor?

Many shamans will claim, of course, that the plants themselves taught humans how to do this. Other commentators point to some mysterious ecological wisdom found only in indigenous peoples. If we put aside these explanations, then I think the answer may be simple. I think people were looking for a better way to vomit.

Cooking the ingredients of the ayahuasca drink

Emetics and purgatives are widely used among the people of the Upper Amazon, who periodically induce vomiting in their children to rid them of the parasitic illnesses that are endemic in the region (Dobkin de Ríos, 1972, p. 127); of the fifty rain forest plants discussed by Taylor (1998), twelve are listed as vermifuges. Vomiting is often induced using the latex of the ojé tree (Ficus insipida), which is widely ingested throughout the Upper Amazon as a vermifuge. Vomiting may be induced in children by giving them piñisma, hen excrement, mixed with verbena (Verbena littoralis) or ñucñopichana (Scoparia dulcis), along with other nauseating components, including pounded cockroaches and urine (Bear, 2000, p. 133, 21).

The Piro believe that eating game leaves residues in the body, which accumulate with time, causing fatigue and depression; vomiting—especially by drinking ayahuasca—expels these residues from the body (Gow, 2001, p. 139). Communal vomiting is also found among indigenous Amazonian peoples. The Achuar Indians drink a hot infusion of guayusa (Ilex guayusa) as a morning stimulant, much as we drink coffee, after which all of them, including the children, vomit together (Duke & Vasquez, 1994, p. 92). Apparently the vomiting is not due to any emetic effect of the drink but, rather, is learned behavior (Lewis et al., 1991).

The beta-carbolines in the ayahuasca vine make it a potent purgative and emetic. Two of the common DMT-containing companion plants, chacruna and sameruca, belong to the same Psychotria genus as the species P. ipecacuanha and P. emetica, both of which are widely used emetics, the former in Brazil and the latter in Peru (Grieve, 1931/1971, pp. 432-434). P. ipecacuanha is, of course, the source of syrup of ipecac, at one time commonly used to cause vomiting in cases of accidental poisoning. A third companion plant, ocoyagé, when added to the ayahuasca drink in the Colombian Vaupés, is called by the Tukano “the ayahuasca that makes you vomit” (Schultes & Hofmann, 1992, p. 121).

If the companion plants have any emetic properties of their own, or resembled other plants with known emetic and purgative properties, it is plausible to hypothesize that the ayahuasca vine and its companion plants were first combined in order to synergize or modulate their emetic and purgative effects, with the serendipitous result of creating an effective delivery form for DMT.

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