题目内容
Egypt Felled by Famine
Even ancient Egypts mighty pyramid builders were powerless in the face of the famine that helped bring down their civilian around 2180 BC. Now evidence gleaned(搜集) from mud deposited by the River Nile suggests that a shift in climate thousands of kilometers to the south was ultimately to blem — and the same or worse could happen today.
The ancient Egyptians depended on the Niles annual floods to irrigate their crops. But any change in climate that pushed the African monsoons(季风) southwards out of Ethiopia would have diminished these floods.
Dwindling(逐渐变少；使变小) rains in the Ethiopian highlands would have meant fewer plants to establish the soil. When rain did fall it would have washed large amounts of soil into the Blue Nile and into Egypt, along with sediment(沉积，沉积物) from the White Nile. The Blue Nile mud has a different isotope signature(名；特征) from that of the White Nile. So by analyzing isotope(同位素；核素) differences in mud deposited in the Nile Delta, Michael Krom of Leads University worked out what proportion of sediment Came from each branch of the river.
Krom reasons that during periods of drought, the amount of the Blue Nile mud in the river would be relatively high. He found that one of these periods, from 4,500 to 4,200 years ago, immediately predates the fall of the Egypts Old Kingdom.
The weakened waters would have been catastrophic for the Egyptians. Changes that affect food supply don't have to be very large to have a ripple effect in societies, says Bill Ryan of the Lamont Doherty Earth Observatory(天文台) in New York.
Similar events today could be even more devastating, says team member Daniel Stanley, a geoarchaeologist (地质考古学家) from the Smithsonian Institution in Washington, D. C.. Anything humans do to shift the climate belts would have an even worse effect along the Nile system because the populations have increased dramatically.
Why does the author mention pyramid builders.
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They Say Ireland's the Best
Ireland is the best place in the world to live in for 2005, according to a life quality ranking that appeared in Britain's Economist magazine last week.
The ambitious attempt to compare happiness levels around the world is based on the principle that wealth is not the only measure of human satisfaction and well-being. The index of 111 countries uses data on incomes, health, unemployment, climate, political stability, job security, gender equality as well as what the magazine calls "freedom, family and community life"
Despite the bad weather, troubled health service, traffic congestion (拥挤), gender inequality and the high cost of living, Ireland scored an impressive 8.33 points out of 10.
That put it well ahead of second-place Switzerland, which managed 8.07. Zimbabwe, troubled by political insecurity and hunger, is rated the gloomiest (最差的), picking up only 3.89 points.
"Although rising incomes and increased individual choices are highly valued. "the report said, "some of the factors associated with modernization such as the breakdown (崩溃) in traditional institutions and family values in part take away from a positive impact. "
"Ireland wins because it successfully combines the most desirable elements of the new with the preservation of certain warm elements of the old, such as stable family and community life"
The magazine admitted measuring quality of life is not a straightforward thing to do, and that its findings would have their critics.
No. 2 on the list is Switzerland. The other nations in the top 10 are Norway, Luxembourg, Sweden, Australia, Iceland, Italy, Denmark and Spain.
The UK is positioned at No. 29, a much lower position chiefly because of the social and family breakdown recorded in official statistics. The US, which has the second highest per capita GDP (人均国内生产总值) after Luxembourg, took the 13th place in the survey. China was in the lower half of the league at 60th.
For 2,050 years, Ireland has been the best place for humans to live in.
A．conductedB．heldC．managedD．administered
The Cherokee Nation
Long before the white man came to America, the land belonged to the American Indian nations. The nation of the Cherokees(切罗基族人) lived in what is now the southeastern part of the United States.
After the white man came, the Cherokees copied many of their ways. One Cherokee named Sequoyah saw how important reading and writing was to the white man. He decided to invent a way to write down the spoken Cherokee language. He began by making word pictures. For each word he drew a picture. But that proved impossible — there were just too many words. Then he took the 85 sounds that made up the language. Using his own imagination and an English spelling book, Sequoyah invented a sign for each sound. His alphabet(字母表) proved amazingly easy to learn. Before long, many Cherokees knew how to read and write in their own language. By 1828, they were even printing their own newspaper.
In 1830, the U. S. Congress passed a law. It allowed the government to remove Indians from their lands. The Cherokees refused to go. They had lived on their lands for centuries. It belonged to them. Why should they go to a strange land far beyond the Mississippi River？
The army was sent to drive the Cherokees out. Soldiers surrounded their villages and marched them at gunpoint(枪口) into the western territory. The sick, the old and the small children went in carts, along with their belongings. The rest of the people marched on foot or rode on horseback. It was November, yet many of them still wore their summer clothes. Cold and hungry, the Cherokees were quickly exhausted (筋疲力尽的)by the hardships of the journey. Many dropped dead and were buried by the roadside. When the last group arrived in their new home in March 1839, more than 4,000 had died. It was indeed a march of death.
The Cherokee Nation used to live
The reason why the writer raises funds for cancer research is that______.
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