In 1985, Swiss-Canadian anthropology student Jeremy Narby spent a year at Quirishari in the Peruvian Amazon, studying how the Ashaninca tribe made use of indigenous resources.
Asking where their knowledge of jungle plants and animals originated, Narby was pointed towards ayahuasceros, shamans who work under the influence of the hallucinogenic plant brew, ayahuasca. They told Narby their knowledge came to them during ayahuasca sessions, and that they were taught by nature itself.

This mystical response seemed to conflict with the Ashaninca's pragmatic relationship to their challenging habitat. But this is just one of many puzzles about Amazon dwellers and their understanding of nature's pharmacopoeia.

Out of more than 80,000 plant species found in Amazonia, how did early shamans stumble upon this potent brew? Ayahuasca has two key ingredients: the psychoactive dimethyltryptamine (DMT), found in several jungle plants, and the Banisteriopsis caapi vine, the "soul" of the brew to ayahuasceros. Chemical inhibitors in the vine prevent DMT from being rendered inactive by stomach enzymes. It's a complex brew. Could shamans really have discovered it through trial and error? And it's just one of hundreds of plant and animal-based preparations, many of which are only now being investigated.

The ayahuasceros said they spoke to serpents, and Narby's own ayahuasca experience had him conversing with a huge snake. Sifting through records of shamanic experiences and creation myths from Australia to Scandinavia, Narby was amazed at how many featured twisted vines, rope ladders, creator serpents and twins, forms he found suggestive of the double helix of DNA. Finding that DNA emits weak but brightly coloured biophotons, Narby suggested these could be the basis for the luminous patterns in the ayahuasceros' visions.

Could the shamans be gaining information from DNA itself? Narby thinks it possible and outlined his theory in The Cosmic Serpent: DNA and the Origins of Knowledge (1998). Although such grand unified theorising is considered anachronistic in contemporary anthropology, Narby's ideas have gained a following among anthropologists, ecologists and psychonauts.
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Hmm... something for you all to ponder on.

The double helix model is not exclusive to DNA structure in nature. I doubt if the shamans were seeing anything related to it . Many tribes use similar mind altering brews to induce trance and meditative states that completly dissolve any logical association with daily facts. The double helix model could have been anything, from coiled snakes to entagled vines, so really to make such an assumption is ignorant at best.

The guy may be a brilliant anthropologist but he is far for being a biologist. They should really have consulted with people investigating brain function under chemical stimuli. It would have given them a lot of clues as to how these shamans recieve those visions and what is the true inspiration behind them.

By the way... Biophotons, or ultraweak photon emissions of biological systems, are weak electromagnetic waves in the optical range of the spectrum - in other words: light. All living cells of plants, animals and human beings emit biophotons which cannot be seen by the naked eye but can be measured by special equipment developed by German researchers. So no brew can make you see things that are beyond your visual spectrum.