Daily Archives: 10 September 2018

by | 10 September 2018 · 5:50 pm

Origin of Camelids

From Skeletons on the Zahara: A True Story of Survival, by Dean King (Little, Brown, 2004), Kindle pp. 127-128:

The nomads owed much to the Arabian camel. By the time their Sanhaja ancestors had acquired the peculiar humped beasts from the east—between the first and fourth centuries A.D.—desertification had long since intensified, clustering people around oases, where they could grow food. As the land grew more arid and infertile, the black tribes migrated south, while the Sanhaja adapted to nomadic life with the camels, living like bedouins long before the first wave of bedouins arrived. Though not considered ruminants, camels, with their complex, three-compartmented stomachs, regurgitate and rechew their forage, turning poor vegetation into protein and energy even better than ruminants do. It was the camel, which could convert scrub brush into nutrient-rich milk, that allowed the Sanhaja to stay on the desert.

Oddly enough, camelids originated not in Africa but in North America. During the Pleistocene epoch, the ancestors of the llama, alpaca, vicuña, and guanaco migrated south to South America, while the ancestors of the camel crossed an erstwhile land bridge at what is now the Bering Strait to Asia. As the camelids were dying out in North America, camels migrated across Eastern Europe, the Middle East, and North Africa. By 3000 B.C., however, wild camels had become extinct in North Africa too. They were reintroduced on the Sahara as desertification increased their utility there, and they quickly became the most important thing a man could own. He who mastered the camel mastered the land.

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by | 10 September 2018 · 5:35 pm

Harshness of the Sahara

From Skeletons on the Zahara: A True Story of Survival, by Dean King (Little, Brown, 2004), Kindle pp. 94-95:

What they looked out on, in 1815, had never been scientifically explored and was almost too mind-boggling to imagine. They faced the western edge of the world’s largest desert. Occupying a third of Africa, it stretches more than three thousand miles east to the Red Sea and twelve hundred miles from the Sahel—the fringe of savanna in the south—to the Atlas Mountains in the north, mountains that snare almost all the moisture traveling down on the northeast winds. Relative-humidity levels, rarely above an abrasive 30 percent, are often as low as a lethal 5 percent, dry enough to kill bacteria and mummify corpses. On the coast, the heat of the Sahara clashes with the cold waters of the Atlantic, often creating heavy fogbanks that envelop the shore, and on many days the irifi, a powerful, searing wind, shrouds the region in a melancholy ocher veil of dust.

The Sahara was not always like this. From 5500 to 2500 B.C., it was relatively fertile, wet and inviting. Up until Roman times, antelope, elephants, rhinoceroses, and giraffes roamed a savanna densely studded with acacia, while crocodiles and hippopotamuses wallowed in lush rivers. Ostriches, gazelles, and antelope still persisted in 1815, but by then the Saharan climate was arguably the most extreme on earth. Its temperature could sizzle at more than 120 degrees Fahrenheit in the shade, the ground temperature soaring 50 degrees higher in the sun; at night, the thermometer could plunge as much as 85 degrees. These conditions, combined with frequent windstorms and less than five inches of average annual rainfall, made sustained life virtually impossible in many parts. As flora and fauna died off or adapted, the land itself deteriorated. While only about a tenth of the Sahara is covered in barren sand dunes, or erg, almost equally formidable are its stepped plains of wind-stripped rock covered in boulders, stones, and dust—the lower elevations generally known as reg and higher ones as hammada.

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by | 10 September 2018 · 5:31 pm

Stages of Dehydration

From Skeletons on the Zahara: A True Story of Survival, by Dean King (Little, Brown, 2004), Kindle pp. 77-78:

It is said that to a thirsty man in a boat, sea spray is a constant torment. It taunts him in its plentitude. It beads on his brow and runs down into his mouth, only to make him thirstier. Inevitably, some of the crew began to crack. A couple of them indulged their increasing fascination with death by leaning over the gunwale and submerging their heads, claiming that they wished to taste what was sure to be their fate.

The stages of dehydration would be categorized a century later by W. J. McGee, a notable amateur thirst-researcher and director of the St. Louis Public Museum. His portrait of the process of human dehydration, which has become the sine qua non of the field, shows five distinct phases: clamorous, cotton-mouth, swollen-tongue, shriveled-tongue, and blood-sweat, each roughly equivalent to a 5 percent decrease in body weight. The Commerces [sailors from the shipwrecked Commerce] had long since grown clamorous: uncomfortable, irritable, feverish. Their stale throats cracked when they spoke. Their fat, sore tongues restricted conversation to terse phrases, and they slurred or lost words. Their hearing had grown muffled, due to loss of moisture in the inner ear. In the cotton-mouth stage, the mind increasingly distorts reality and desires. Sufferers rashly toss off clothes or possessions or, in the case of the Commerces, become obsessed with how it would feel to die in the sea. It is normal for spells of feverish dreams to focus on the urge to drink, and the Commerces, parched beyond imagination and penetrated by salt, extolled the lush banks of the Connecticut River and craved a cup—or a barrel—of the delicious mineral water from the freshets that filled it. In his head, Riley built and rebuilt the stately spa he had dreamed of.

That afternoon, Riley gave up any hope of a rescue at sea. To continue on meant certain death, roasting on the woeful collection of planks that formed their boat, now an inhuman prison cell that confined their bodies in cramped agony. They might fight on another handful of days, but they did not have enough food and water to maintain their strength. They would soon lose the power to affect their fate.

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