Cold (33 page)

An hour ago, spring came to the Pleistocene. At first, the ice sheets thinned without pulling back. The thinning ice dumped
water into the oceans. Sea level rose. The shoreline of northern North America was for the most part one long stretch of tidewater
glacier. But then the ice sheets pulled back, melting at their edges. The earth’s surface, relieved of all this weight, rebounded.
Bay bottoms and coastal waters became mudflats and then salt marshes and then forests. What is now Lake Champlain between
New York and Vermont was then part of the Champlain Sea, which covered Ottawa, Montreal, and Quebec City for two thousand
years — actual years, not the fast-forwarded-model years needed to put vast lengths of time into perspective, but two thousand
winters and summers, twenty centuries. Its early shorelines were cliffs of ice. Bowhead, finback, and humpback whales swam
between those shorelines. Harbor porpoises frolicked about. Ringed seals basked on the frozen surface in early spring. As
those two thousand years went on, the land rebounded. The Champlain Sea drained, leaving little more than Lake Champlain,
the fossils of whales and seals and cold-water clams, and isolated patches of beach grass and sea rocket far inland from the
Atlantic. The same pattern happened all along the coast. In Maine, Augusta and Bangor rose up from underwater. The now extinct
Tyrrell Sea shrank to become Hudson Bay, surrounded by rows of terrestrial beach terraces that speak of a former glory.

On land, retreating ice left barren ground, scraped of all vegetation, covered with rock rubble and piles of boulders and
stones ground into flour. Wind sliding down the face of the ice sheets tossed the flour into violent sandstorms. In places,
great blocks of ice fell from the faces of retreating ice sheets. Blowing dirt built up around them, and when they melted,
they left in place the kettle lakes of the prairie states and Washington and New York states. In other places, the blowing
dirt — sand and flour that the glaciers ground from bedrock — covered vast areas of ice, insulating it. This ice, insulated
beneath soil, stagnated. Grasses and later forests grew in the soil, with the stagnant ice beneath. Eventually, the stagnant
ice melted, and the ground, deprived of the subterranean ice, subsided. What had been upland forests sank into lowlands, wetlands,
and swampy depressions.

One seed at a time, plants moved onto the quickly changing ground. Marsh marigold, mountain monkshood, and mountain harebell
all moved south from Beringia. Plants with wind-borne seeds moved faster than those that hitched rides in the guts of animals.
Hickories were among the slowest, taking two thousand years to journey up the Mississippi Valley and then east to Connecticut.
Chestnuts, too, crawled along, averaging a mile or so every ten years. Hemlocks and maples were twice as fast. Certain oaks
sprinted at more than two miles every ten years, neck and neck with eastern white pines.

As the land changed and new plants arrived, the forests changed. Pines replaced spruces. Balsam firs, birches, elms, and oaks
replaced pines. At certain places and certain times, forests changed during the course of a human lifetime.

As the ice melted and the land rebounded, great rivers and their drainages changed, too. Arctic grayling, northern pike, and
lake whitefish survived glaciation in the Yukon River and its tributaries, then migrated into the Mackenzie River. They did
not migrate along coastal waters, but rather through a lake that formed as the glaciers melted, a lake that joined the two
rivers, another open gate. Great Bear Lake, Great Slave Lake, and Lake Athabasca were at one time part of Lake McConnell,
which drained for a time into the Mississippi River and for a time into the Mackenzie River and then into what would become
Lake Superior, switching back and forth as floodgates of ice opened and closed. Certain fish evolved for a while behind the
gates, then spread out when the gates were opened. The northern pike and burbot of Alaska hail from Beringia, but the northern
pike and burbot of the lower states hail from waters south of the ice sheets. Genetically, they are not the same.

Humans passed through the gates more than once. They came, it seems, as early as forty thousand years ago, but these early
North Americans left little behind. What little they did leave was primitive and crude, nothing more than rocks with an edge,
the kind of thing that one might pick up and skim across a lake without noticing that it had once been worked by human hands.
The more recent Clovis people left stuff lying around, pretty stuff, symmetrically carved functional art. The first remnants
of the Clovis people found in modern times were in New Mexico, but ongoing searches have turned up Clovis sites throughout
the United States and down into Mexico and even Central America. At sites dated to thirteen thousand years ago, the Clovis
people left spear tips and knives and scrapers made of chipped stone, bones marked by the signs of butchering, and rocks burned
red. Most abundantly, they left stone flakes, fine chips of stone, the waste from working rocks into more useful tools. They
ate more than 125 species of plants and animals, including mammoths. Although what they wore is unknown, it seems likely that
they would have had the sense to wear skins in cold weather. Closer to the ice, with the wind ripping down from the ice sheets,
it seems obvious that they would have worn one layer of fur turned in toward the body and another with the fur turned out.

Around the time of the Clovis people, the mammoth disappeared. Other animals believed to be on the Clovis people’s menu also
disappeared: North American camels, two kinds of deer, two kinds of pronghorn, a kind of llama, the stag moose, the shrub
ox, the woodland musk ox, five species of the American horse, and mastodons. Giant beavers, as big as today’s black bears,
disappeared. The American cheetah, the dire wolf, the saber-toothed tiger, the short-faced bear, and the American lion all
disappeared. Smaller mammals — the sort some believe less likely to show up on a menu — survived. Certain scientists saw this
as circumstantial evidence and blamed the Clovis people for the extinctions, but other scientists argued that there were more
clues to consider. To anyone who has hunted an elephant or a musk ox or a moose with a stone spear, the starring role of man
in these extinctions seems miscast. More likely, humans helped the extinctions along as the animals succumbed to a rapidly
warming environment — roaring winds blowing from melting glaciers and sandstorms carrying megatons of glacial flour. They
succumbed to a sudden change that likely made winters and summers even more uncertain than they had been during the Little
Ice Age. It was a time when grasslands became forests, forests were buried in drifting sand, and massive lakes drained overnight
— a lake one day, a mud bed the next — through white-water torrents bigger than today’s Mississippi River. Tallgrass prairies
became shortgrass prairies. The Arctic steppe of Beringia became overgrown with shrubs and then trees before disappearing
altogether under the rising Bering Sea. Disease, too, may have played a role in these extinctions. But this much is certain:
the big mammals were there, south of the ice, and they were in Beringia, north of the ice, and when the ice melted, many of
them disappeared.

Within a few hundred years of the extinctions, on the other side of the world, the Sumerians were busily inventing agriculture.
But in North America, the hunt went on. Bison were still abundant, and various deer, and the delicately sized and flavored
modern beaver. Grizzly bears kept the hunt exciting. Clovis boys sat around campfires and, with the timeless cockiness of
teenagers, mocked the stories of ice sheets and mammoths and mastodons, and of a great-uncle who had been eaten by a saber-toothed
tiger. The boys focused on their own prowess at hunting buffalo and on near misses with grizzlies. But occasionally they stumbled
upon bones, upon tusks and teeth of mammoths and mastodons, and they may have wandered through boulder-strewn forests and
grasslands, perhaps even having their own word for erratics, wondering why such large rocks would be resting so far from anything
resembling a mountain.

It is May sixth and warm in Anchorage, truly spring. To celebrate, I take my caterpillars Fram and Bedford from the freezer.
They have been on ice since September twenty-third. I put the frozen but presumably undead bodies of my two patients in a
mason jar lined with the budding leaves of birch and willow and sambucus. Optimistically, I poke airholes in the jar’s lid.
I also take out my frozen mud, collected in September and stored in the freezer ever since. I open the jar to let the mud
thaw.

The Anchorage paper runs a full-page article on mosquito evolution. For the past five years, a pair of scientists have created
the climate of New Jersey in an Oregon laboratory. The climate chambers have been stocked with mosquitoes from Maine. From
the perspective of scientific inquiry, storing Maine mosquitoes in Oregon climate chambers that mimic New Jersey conditions
is business as usual. The way things are going, Maine’s climate will be New Jersey’s climate in the foreseeable future. The
mosquitoes have already shaved two weeks off their hibernation time. “In a woodsy bog on the road between Millinocket and
Baxter State Park,” the paper says, “a mosquito that can barely fly is emerging as one of climate change’s early winners.”
The mosquito may have had a trick or two to show the mammoth, North American camel, llama, deer, prong-horn, stag moose, shrub
ox, woodland musk ox, American horses, and mastodons.

Mammoths occasionally materialize out of thawing soil where rivers cut into banks of permafrost or where miners dig into icy
gravel. Their tusks stand out, or blackened femurs as big as fence posts, or skulls with a large central aperture for the
trunk. The skulls at different times have been mistaken for the skulls of unicorns and Cyclopes. In the past few centuries,
more than fifty thousand tusks have been exported from the Taymyr Peninsula in Russia. Today Alaskans market mammoth tusks
as expensive souvenirs.

In 1977, a Russian miner working near the Dima River found a frozen carcass — not a skeleton, but a frozen carcass, covered
with hair, frozen eyes intact and staring. In his excitement, he reportedly called out,
“Mamonyonok!”
— “Baby mammoth!” Frozen mammoths tend to be named. This one was named Dima, after the river. Before the miners could attract
the attention of officials, Dima’s carcass thawed enough to stink. Nevertheless, Dima’s heart and foot-long penis are displayed
today in the St. Petersburg Zoological Museum.

Dima was neither the first nor the last. Chinese writings from the second century b.c. describe thawing mammoth remains, saying
they were “found beneath the ice, in the midst of the ground.” The Chinese text talks of flesh weighing a thousand pounds
that “may be used as dried meat for food.” It indicates that rats flocked to a thawing carcass: “Wherever its hair may be
found, rats are sure to flock together.”

In 1901, the Russian Imperial Academy of Science heard of a carcass frozen in a cliff on the Berezovka River, above the Arctic
Circle. Scientists traveled by Siberian Express, wagons, boats, and horse-drawn sleds to reach the site. By the time they
arrived, wolves and foxes had devoured part of the mammoth. Local people had taken the tusks. Eugene Pfizenmayer, one of the
scientists, wrote:

Some time before the mammoth body came in view I smelt its anything but pleasant odor — like the smell of a badly kept stable
heavily blended with that of offal. Then, round a bend in the path, the towering skull appeared, and we stood at the grave
of the diluvial monster. The body and limbs still stuck partially in the masses of earth along with which the corpse had been
precipitated in a big fall from the bank of ice.

The scientists built a shelter over the mammoth and went about dismembering what was left of it. They learned that it had
four toes and a flap of skin protecting its anus from the cold. They preserved its flesh with alum and salt, then shipped
the whole thing to St. Petersburg. One of them wrote, “A thorough washing failed to remove the horrible smell from our hands.”
The trip back to St. Petersburg, via sled at temperatures as low as sixty-seven below, began on October 15, 1901, and ended
on February 18, 1902. Summed up, the expedition north, the butchering of the frozen mammoth, and the trip home took 291 days.
Tsar Nicholas and Empress Alexandra viewed the carcass in St. Petersburg. The empress held a handkerchief to her nose. “Is
there something else interesting to show me in this museum,” she said, “as far away from this as possible?”