“Big surges of water would sluice around the locks and scour bypasses into the dirt. Once one of the lock walls started to tumble, that would be the end. All of Gatun Lake could spill.” He pauses. “That is, if it hadn’t already emptied into the Caribbean. After 20 years with no maintenance, I don’t see earthen dams left. Especially Gatun.”
At that point, the liberated Chagres River, which drove many French and American engineers crazy and thousands of laborers to their death, would seek its old channel to the sea. With the dams gone, the lakes empty, and the river again headed east, the Pacific side of the Panama Canal would dry up, and the Americas would be reunited.
The last time that happened, 3 million years ago, one of the greatest biological interchanges in Earth’s history commenced as North and South American land species began to travel the Central American isthmus, which now joined them.
Until then, the two landmasses had been separated since the supercontinent of Pangea began to break up about 200 million years earlier. During that time, the two separate Americas had embarked on enormously different evolutionary experiments. Like Australia, South America developed a menagerie of marsupial mammals, ranging from sloths to even a lion that carried its young in a pouch. In North America, a more efficient, ultimately triumphant placental path emerged.
This most recent man-made separation has existed for little more than a century—not enough time for any meaningful species evolution, and a canal barely wide enough for two ships to pass each other has hardly been much of a barrier. Still, speculates Bill Huff, until roots work their way into the cracks in the huge, empty concrete boxes that once held ocean-going vessels and finally shatter them, for a few centuries they will be rain-catch holes prowled by panthers and jaguars, as regenerating tapir, white-tailed deer, and anteaters come to drink.
Even longer than those boxes, for a while a big man-made, V-shaped gouge would remain, marking the place where humans undertook, in the words of Theodore Roosevelt after he went to Panama in 1906 to see for himself, “the greatest engineering feat of the ages. The effect of their work,” he added, “will be felt while our civilization lasts.”
If we disappeared, the words of this larger-than-life American president, who founded a national park system and institutionalized North American imperialism, would prove prophetic. Yet long after the walls of the Culebra Cut cave in, one last larger-than-life monument to Roosevelt’s grand vision for the Americas will remain.
IN 1923, SCULPTOR Gutzon Borglum was commissioned to immortalize the greatest American presidents in portraits every bit as imposing as that long-vanished wonder, the Colossus of Rhodes. His canvas was an entire South Dakota mountainside. Along with George Washington, father of the country; Thomas Jefferson, drafter of its Declaration of Independence and Bill of Rights; and Abraham Lincoln, the emancipator and reuniter, Borglum insisted on portraying Theodore Roosevelt, who joined the seas.
The site he selected for what qualifies as the United States’ national magnum opus, Mount Rushmore, is a 5,725-foot uplift composed of fine-grained Precambrian granite. When Borglum died in 1941 of a brain hemorrhage, he’d barely begun work on the presidential torsos. But the faces were all indelibly carved in stone; he lived to see the visage of his personal hero, Teddy Roosevelt, officially dedicated in 1939.
He’d even rendered Roosevelt’s trademark pince-nez in rock—a rock formed 1.5 billion years ago, among the most resistant on the continent. According to geologists, Mount Rushmore’s granite erodes only one inch every 10,000 years. At that rate, barring asteroid collision or a particularly violent earthquake in this seismically stable center of the continent, at least vestiges of Roosevelt’s 60-foot likeness, memorializing his Canal, will be around for the next 7.2 million years.
In less time than that,
CHAPTER 13
The World Without War
WAR CAN DAMN Earthly ecosystems to hell: witness Vietnam’s poisoned jungles. Yet without chemical additives, war curiously has often been nature’s salvation. During Nicaragua’s Contra War of the 1980s, with shellfish and timber exploitation paralyzed along the Miskito Coast, exhausted lobster beds and stands of Caribbean pine impressively rebounded.
That took less than a decade. And in just 50 years without humans….
THE HILLSIDE IS heavily booby-trapped, which is why Ma Yong-Un admires it. Or rather, he admires the mature stands of daimyo oak, Korean willow, and bird cherry growing wherever land mines have kept people out.
Ma Yong-Un, who coordinates international campaigns at the Korean Federation for Environmental Movement, is climbing through cottony November fog in a white propane-powered Kia van. His companions are conservation specialist Ahn Chang-Hee, wetlands ecologist Kim Kyung-Won, and wildlife photographers Park Jong- Hak and Jin Ik-Tae. They’ve just cleared a South Korean military checkpoint, slaloming through a maze of black and yellow concrete barriers as they entered this restricted area. The guards, in winter camouflage fatigues, set aside their Ml6s to greet the KFEM team—since the last time they were here, a year earlier, a sign was added stating that this post is also an environmental checkpoint for preservation of red-crowned cranes.
While waiting for their paperwork, Kim Kyung-Won had made note of several gray-headed woodpeckers, a pair of long-tailed tits, and the bell-like singing of a Chinese bulbul in the dense brush around the checkpoint. Now, as the van ascends, they flush a brace of ring-necked pheasants and several azure-winged magpies, beautiful birds no longer common elsewhere in Korea.
They have entered a strip of land five kilometers deep that lies just below South Korea’s northern limit, called the Civilian Control Zone. Nearly no one has lived in the CCZ for half a century, although farmers have been permitted to grow rice and ginseng here. Five more kilometers of dirt road, flanked by barbed wire filled with perching turtle doves and hung with red triangles warning of more minefields, and they reach a sign in Korean and English that says they are entering the Demilitarized Zone.
The DMZ, as it is called even in Korea, is 151 miles long and 2.5 miles wide, and has been a world essentially without people since September 6, 1953. A final exchange of prisoners had ended the Korean War— except, like the conflict that tore Cyprus in two, it never really ended. The division of the Korean Peninsula had begun when the Soviet Union declared war on Japan late in World War II, on the same day that the United States dropped a nuclear warhead on Hiroshima. Within a week, that war was over. An agreement by the Americans and the Soviets to split the administration of Korea, which Japan had occupied since 1910, became the hottest point of contact for what became known as the Cold War.
Abetted by its Chinese and Soviet communist mentors, North Korea invaded the South in 1950. Eventually, United Nations forces pushed them back. A 1953 truce ended what had become a stalemate along the original dividing line, the 38th parallel. A strip two kilometers on either side of it became the no-man’s-land known as the Demilitarized Zone.
Much of the DMZ runs through mountains. Where it follows the courses of rivers and streams, the actual demarcation line is in bottomland where, for 5,000 years before the hostilities began, people grew rice. Their abandoned paddies are now sown thickly with land mines. Since the armistice in 1953, other than brief military patrols or desperate, fleeing North Koreans, humans have barely set foot here.
In their absence, the netherworld between these enemy doppelgangers has filled with creatures that had practically nowhere else to go. One of the world’s most dangerous places became one of its most important— though inadvertent—refuges for wildlife that might otherwise have disappeared. Asiatic black bears, Eurasian lynx, musk deer, Chinese water deer, yellow-throated marten, an endangered mountain goat known as the goral, and the
