An Odyssey of Wonder from the Aztecs to the Quantum World – The Marginalian
A recent visit to Teotihuacán – an ancient city of Mesoamerica in modern Mexico, built by ancient cultures around 600 BCE and later rediscovered by the Aztecs – left me amazed to see our search for truth and our search for meaning, with a rare combination of chemistry, culture, and chance that changes its face to face my reality.
Located at the base of a dormant volcano, Teotihuacán surprised the Toltec settlers with the discovery of a shiny black substance between stone and glass, brittle but strong, breathtakingly beautiful. Soon, they were working in obsidian workshops by the thousands, making from them delicate jewelry and beads and deadly weapons, household tools and ritual figurines, mirrors and surgical instruments, which traveled the trade routes to become the backbone of the Toltec economy. Its abundance and versatility may be the reason why they never got around to metallurgy, but obsidian was as important to the development of their civilization as iron has been to ours.
It would also be the ouroboros of their civilization – the source of prosperity by which they would prosper for centuries and the terrible ruler by which they would perish.
It is not a mineral but a volcanic glass made from igneous rock, obsidian forms as the lava cools rapidly so that the mineral crystals can nucleate. It is composed mainly of silicon dioxide, with trace amounts of various oxides – mainly aluminum, iron, potassium, sodium, and calcium – the ratio of which varies with the conditions of each explosion, creating a specific chemical fingerprint, so that each piece of obsidian can now be traced to its original source using nuclear and X-ray analysis.
As if the volcanic glass wasn't already amazing enough, the discovery of a special type of obsidian – iridescent, with a green-gold sheen – made Teotihuacán reach the status of a great ancient city. Rainbow obsidian soon became the most important type of obsidian in Mesoamerica, attracting people from distant lands in search of riches, just as the Gold Rush changed the population of North America in the nineteenth century.
With the discovery of this double-glazed obsidian, Teotihuacán became home to people from different cultures with no common language and no common culture. And yet they lived together in harmony in a fertile valley, sharing its wealth – it is difficult to fight while it is prosperous – until the eruption of a different volcano in present-day Ecuador caused a change in the climate of the region that sent the whole environment in a short time and left Teotihuacán on the brink of starvation. Suddenly, the foundation of this composite society began to crack across class lines as nobles feasted and starving workers fought for resources. A kind of civil war broke out, from which Teotihuacán never recovered. The survivors left the city, but not before burning down the residences of the ruling class. Only its towers – the Toltec temples of the Sun and the Moon – were standing strong when the Aztecs arrived about a thousand years later and named it “City of the Gods.”
One of the geochemical wonders of this Earth, iridescent obsidian occurs when nanoparticles of magnetite – iron oxide present in most obsidian – form a thin film that reflects light waves at the upper and lower boundaries of the material in such a way that they interfere with each other, increasing the reflection of some wavelengths and reducing others. This process, known as thin-film interference, is what produces the colorful glow of oil spills and soap bubbles.
Magnetite gave Teotihuacán its rainbow obsidian, but it also inspired the destruction of Mesoamerican civilization by the Spanish. Humans discovered the magnetic field by using naturally magnetic pieces of rock containing magnetite, known as lodestones, which became the first magnetic compass, changing the direction of travel. Without magnetite, Columbus may have ended up with another unknown sailor who was shipwrecked on an unknown shore.
Seemingly a triumph of human nature's ingenuity, the invention of the compass was simply a contradiction of nature's own thought: Magnetite crystals were found in the upper beaks of homing pigeons and many migratory birds – a kind of built-in compass that allows them to look closely at the moving parts of the Earth. (Small amounts of magnetite are also found in various areas of the human brain, including the hippocampus – the crucible of our autonoeic consciousness; my friend Lia is convinced that my homing-pigeon sense of direction, which overfills the smallness of my other senses, is due to unusual amounts of magnetite in my brain.
The built-in compass explains why, for example, bar-tailed godwits – some of the longest-distance migrants on Earth – can leave their breeding grounds in Alaska and head to their breeding grounds in New Zealand not near the continental arc of Asia and the edge of Australia, where they can easily go by visible landmarks such as mountains and cities, but over the open sea of the Pacific Ocean. Across the deep blue, where an error of even half a degree can take them to a completely different place, they find their way year after year, eon after eon.
Geologist and geologist Joe Kirschvink discovered magnetite while studying bees and pigeons as a graduate student at Princeton University in the 1970s. The idea that some animals moved by magnets was not new. At the turn of the century, Belgian playwright and novice apiarist Maurice Maeterlinck observed that bees navigated by “feelings and aspects of matter completely unknown to us,” which he called “magnetic intuition.” A generation before him, and ten years before Darwin shook the world with his theory of evolution, the Russian zoologist and explorer Alexander Theodor von Middendorff predicted:
The amazing persistence of migratory birds – despite the wind and weather, despite the night and fog – may be because the birds are always aware of the direction of the magnetic pole and therefore know exactly how to keep where they are going.
Finding the basis of biomagnetism in magnetite was seen as a triumph of science over mystery. But in the decades since then, as our instruments have become more sophisticated and our theories have been tested more, research has revealed the presence of a protein in the retinal cells of birds – cryptochrome – which may use quantum entanglement to provide another method of magnetoreception. More information has only made it more mysterious: A complete system may include many built-in tools that interact with many important laws and forces. I think of Henry Beston, who wrote a hundred years ago that “in a world older and more perfect than ours,” some animals “go about complete and perfect, gifted with extensions of senses that we have lost or never attained, living with words we cannot hear.” I think about the difference between science and civilization: Science knows that it is not finished, an endless process, while every civilization mistakes itself at the end of progress.
Walking down the central area of Teotihuacán and watching the pyramid of the Sun slowly eclipse the volcano, the triumph of evolution of my peripheral vision registers a yellow light. I turn around to see a small bird burning in the ruins, sitting on the edge of a rock above a man wearing a sombrero selling obsidian souvenirs. Warblers – fearless, non-commercial, needing only the sky and song – are among the most common transgressors between North and South America, their migration routes stretching from Alaska to the Amazon. Older than the Toltecs, older than the remains of the scale that divided the Atlantic and Pacific Oceans to enclose the Americas, older than our old myths, they saw civilizations rise and fall, and one day they will see Hollywood full of poppies and Manhattan back to the sea. And when they fly over the ruins of the Sistine Chapel and Silicon Valley, they will be guided by the same mysterious forces that guided the first of their kind.
“From a basic biological perspective,” concluded the team of scientists examining the warbler's magnetic compass, “magnetic field perception is still the only known sense of whether the sensor and its location exist.”
It is to our advantage to have frequent reminders that we do not understand many of the mysteries of nature because we do not understand them, and may never understand them ourselves; that all our creative restlessness, every beauty and object we've ever made – our temples and our visions, the Moonlight Sonata and the general relativity – arose from our encounter with the mystery of which we are a part. The Toltecs and Aztecs gave a mystical make-up to Quetzalcoatl – their feathered god of creation and knowledge – who gazed at me from the bottom of the tower with stony calm for centuries, knowing everything and knowing nothing.
