The Universe Within (10 page)

Rocks and bodies contain more than clocks: they also hold
calendars. Slice a coral, and you will find that the walls of the skeleton are layered with light and dark bands. As they grow, corals add layers of mineral to their skeletons, almost like slapping plaster on a wall. The ways that the mineral forms depend on sunlight, so the variation in the layers reflects the waxing and waning of each passing day. Mineral growth is fastest in summer, when the
days are long, and slowest in winter, when the days are short. Consequently, bands deposited in summer months will be thicker than those at other times of the year. Count the number of layers embedded in each cycle of thick and thin layers, and what do you find? Three hundred sixty-five of them. Coral skeletons can be an almanac of days of the year.

The beauty of corals lies not only in the reefs that reveal the splendor of the underwater world but in the insights they give us into our past. Crack rocks along the sides of roads in Iowa, Texas, even north into
Canada, and you will see
coral reefs that once thrived in ancient seas hundreds of millions of years ago. The city of Chicago is built upon an ancient coral reef. And reefs like these tell the story of how time itself has changed. Go to fossil reefs 400 million years old, and you will find four hundred layers inside the corals—suggesting that each year was actually four hundred days long and contained a whopping thirty-five more days than our current year. What accounts for this discrepancy? Since the duration of a year is fixed by Earth’s
rotation about the sun, the days must have been shorter 400 million years ago than they are today. To make the algebra work, each day had to have been twenty-two hours in length. In the eons since those corals were formed, two hours have been added to every day.

Like a
slowing top, Earth spins slower and slower with each passing moment, making days longer now than in the past. As
the planet
rotates, the water in the oceans moves about and serves to brake the spin of the planet. That is why today is two milliseconds longer than yesterday.

Fossil corals are silent witnesses to the lengthening of days.
Clocks and calendars abound in the natural world, sometimes in the most surprising places.

In the rush of pitching my tent, I inadvertently left a hummock of tundra under the floor. With a mound in the center and slick nylon surfaces inside, my sleeping bag slid to one corner each time I drifted to sleep. After a frustrating few hours of writhing like a pupa in a cocoon, I became determined to find a flat surface, and in a fit of fatigue and desperation I jury-rigged one by contorting myself over heaps of clothes, books, and field gear. It was a good thing we expended a lot of energy that first day setting up camp; my exhaustion led me to a reasonable facsimile of sleep.

I arose to the bright morning sun and dressed quickly, not wanting to hold the team back. Today would be our first day in
Greenland looking for fossils, and the excitement made me surprisingly alert despite the fitful rest.

I made my way to the kitchen tent, my first goal being to get the coffee going. Our field gear was packed so tightly for the trip north that simply finding the breakfast containers was no small task. After about ten minutes of fumbling with the packing lists and crates, I broke out some cooking supplies and got the java brewing.

Life was good. It was a clear, bright Arctic summer morning. The dry air made images incredibly sharp; features in the distance looked as if they were right next door even though they
were miles away. Warming my fingers against the coffee mug, and relishing the stillness, I walked in my mind through the different hills I was going to hike that day.

After a few cups and about twenty minutes of savoring the calm, I realized something was wrong. The world was still, a bit too much so. With each passing minute of silence, I began to feel more alone.

A glance at the clock revealed the cause for my solitude: it was 2:00 a.m. Yet here I sat, fully dressed, primed for a whole new day, and bristling with energy. I felt like a total chump, albeit a well-caffeinated one. Returning to sleep was an impossibility, so I broke out a novel I was saving for a snowy day and struggled to read for the next few hours until my companions arose.

It was the light, of course. The walls of my tent did not block it out, leaving the inside illuminated at all hours. My
brain, acclimated to the southern world, was completely in tune with the equation “light equals day and dark equals night.” Because that simple relationship was lacking in the twenty-four-hour daylight of Arctic summer, my brain’s usual cues were utterly useless. My sleeping colleagues, old hands at fieldwork, prepared by bringing eyeshades, while all I had was a flashlight.

Those first few days were a real jangle. I felt off-kilter, as if the insides of my body were struggling to keep up with a whole new planet. Think of a major case of
jet lag, but without any night whatsoever, the only reference point comes from a clock. The longer I dwelled in the landscape, though, the more my brain became attuned to it. The sun traces a large ellipse through the sky, casting different shadows throughout the day. Almost without thinking, the brain begins to make a sundial out of any standing object. Of course, in the high Arctic we lack trees; any large rock or tent ends up doing the job.

From jet travel we all know that our sleeping and wakefulness are matched to the sun. Virtually every part of us—every organ, tissue, and cell inside—is set to a rhythm of day and night.
Kidneys
slow down at night. That’s a wonderful trait if you want to minimize trips outside bed—something very useful when inside a sleeping bag in the Arctic.
Body temperatures vary over the course of the day, with the coolest ones happening at 3:00 a.m.
Liver function is time dependent as well: the human liver works slowest in the morning hours, meaning the cheapest dates would be at breakfast.

Our bodies respond to more than days; they also are tied to
seasons. The changes from winter to summer bring new patterns of light, temperature, and rainfall. Animals are tied to these in the ways they feed and reproduce, and humans are no different. Even our moods relate to the season. By some estimates 1.4 percent of Floridians suffer from
seasonal affective disorder, compared with 14 percent of New Hampshire residents.

Drunks see time flying by, with the party just getting going as everybody leaves. Cannabis brings an eternity to a twenty-minute episode of
The Three Stooges
. Intense concentration or emotions make us lose track of time. Even the proverbial “watched pot” that never boils is a statement about how our
perception of time is sometimes at odds with the clock itself.

In 1963, a young French geologist had a plan to change the way we think about time. By the age of twenty-three,
Michel Siffre had visited some of the largest unexplored patches of Earth. These were underground, and by mapping the world below, Siffre revealed vast caverns and glaciers inside the Alps. The subterranean landscape is a beautiful and dark world, and in this void Siffre was inspired to ask a whole new question.

What happens when people completely disconnect from the clock? Each of us is a slave to it: we chop our days into little moments and plan our lives around them. Not only do we live in a world defined by natural time—the dark of night and the light of day, the warmth of summer and the cold of winter—but
we have inserted man-made inventions into this equation. Beepers, buzzers, and alarms tether us to each passing moment. What happens when we completely cut the cord that binds us to these stimuli?

Siffre intended to be his own lab rat and concocted a plan to live for two months in a cavern two hundred feet belowground, completely removed from normal human existence. He would bring food, a sleeping cot, and
artificial light, but—and this is the important point—no timepiece or anything that could even indirectly give a clue as to time. Siffre’s only connection to the outside world was a telephone with which he called his friends on the surface to inform them of the times he spent awake and asleep. The plan was for a sixty-day disconnect from the normal light-dark cycles of our world and from our clocks that are based on them.

A meticulous note taker, Siffre dutifully recorded each passing day on a calendar with his bodily functions and mental states. His diaries record his daily movements, his body temperature, his mood, and his libido.

On the thirty-seventh day of his records, with twenty-three days yet to go, Siffre was on the phone with a colleague from above. Pierre, one of his chums, asked, “How much time in advance do you want to be warned that your experiment is about to end?”

“At least two days to gather up my things.”

“Start getting ready,” Pierre responded. The experiment was over. By relying solely on his mental clock, Siffre had lost twenty-three days.

What happened?

One answer lay inside Siffre’s diaries. Having recorded when he woke and went to sleep, he called his friends when he was able so that they could log the real time for him. But lacking a watch or alarm clock, he had no idea how long each interval of sleep
really was. What he perceived as brief ten-minute catnaps were in reality eight-hour slumbers.

His misperception of time ran deep. At one point in the experiment, Siffre called his friends to see if he could mark off two minutes simply by counting. Most of us can pace this off roughly, within ten seconds or so. Siffre began counting from 1 to 120, in an attempt to march off the seconds in two minutes. This simple task took him five minutes.

When the team crunched the numbers in Siffre’s diary, they came to a fundamental realization. The hours of Siffre’s biological day, when he slept and was awake, were not some wandering, random affair. The number of hours he slumbered and those he was awake almost always totaled close to twenty-four. A rest-activity cycle of twenty-four hours is a close approximation of life on the surface. Siffre’s perception of time underground was completely off, but his bodily cycles marched along at an earthly pace.

Word of Siffre’s feat ignited a fad of
isolation research. In the years since his time in the cave, volunteers have endured
sensory deprivation while gizmos recorded their vital signs, brain activity, and behaviors. Some have sat for weeks or months in chambers with light either restricted or tightly controlled. Other people have attempted the truly extreme, like the sculptor who entered an isolation experiment in a chamber with the goal of living in complete darkness for months. That experiment had to be scuttled after only a few days when he started to lose his grip on reality.

Through all of this sensory deprivation, one consistent pattern emerges. Many of the biological urges we experience—
sleep, hunger, and sexual cravings—cycle at a regular pace regardless of whether we live in a dark cave, room, or any other isolated environment. Time exists on the clock, in our perceptions of it, and somewhere deep inside us.

Curt Richter had an inauspicious beginning to a scientific career. After a stint in the army during World War I, he entered the
Johns Hopkins University to explore the extent to which animal behaviors are based on inborn instinct. He arrived in Baltimore in 1919 to work with a senior scientist already famous for his work in the field. Unknown to Richter, his new adviser had an offbeat way of training students. Richter was given the usual trappings of a graduate student’s existence: a little office in which to study, a library card, and some supplies. Once established with his kit, Richter was left completely on his own. Each day consisted of no set meetings, no required courses, no seminars; it was an existence with no structure whatsoever. There would be no babying, for this was a sink-or-swim introduction to a scientific career.

Soon after Richter established himself in Baltimore, his adviser handed him a cage with twelve normal rats inside. His instruction to Richter was as simple as it was intimidating: “Do a good piece of research.”

Richter began by feeding the rats some bread and staring at them for days on end. Like a good scientist, he started to record details about their daily lives: when they ate and what they did. Then one day he made the observation that changed his career and ultimately launched an entire new field of science. As he reminisced years later, when describing his rats, “They just jumped around the cage for long periods and then were quiet again.”