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1、The Development of WritingFew people would disagree with the belief that primitive man learned to speak long before he developed a system of writing. But while his early spoken language may have been nothing more than a few sounds, early man could transmit messages across distances by means of signa
2、ls from drums, smoke and fire. It was probably a desire to record messages that led to the development of alphabets. For early man, who could speak and who could send messages, could not put those messages into permanent form. The desire to have permanent records may not be easily understood in toda
3、ys world where electronic science has made disk and tape recordings commonplace. If early man wanted to leave records of past events to remind him of good times and bad, he had to depend on his memory, and on primitive markings such as piles of stones, cuttings on sticks, etc. The limitations of thi
4、s system led early man to turn to rock drawings for the expression of sophisticated ideas. This form of writing depended on pictures to convey ideas, and although more advanced than previous developments, it was still too limited for man to be entirely satisfied. Man finally was able to develop a sy
5、stem of picture writing that associated symbols and sound. This system, which was originated by the early Sumerians and the Egyptians more than 3,000 B.C., is based on the same principle that we sue today in most world alphabets. It was about 1,000 B.C. that the Phoenicians took the complicated pict
6、ure alphabets of the Egyptians and simplified then into about 30 symbols, each one standing for a consonant sound. Finally, the ancient Greeks, about 800 B.C., refined this Phoenician alphabet and added signs for vowel sounds. The alphabet used in English, an din many other world languages, is calle
7、d the Roman alphabet because it was developed by the Romans who had taken most of it from another Italic people, the Etruscan, who, in their turn, had learned it from the ancient Greeks. Letters on ancient monuments in Rome prove that the Roman alphabet, the same alphabet used today, had been perfec
8、ted by A.D. 114. Secret to Longevity Lies in Genes, Study FindsTue Jun 11, 5:16 PM ETby Maggie Fox, Health and Sciences CorrespondentWASHINGTON (Reuters) Want to live to be 100? Pick old grandparents. Its an old irony, but researchers said on Tuesday they had shown this is remarkably true when it co
9、mes to surviving into old age, and they believe a cluster of just a few genes may be responsible. They have set up a company that studies centenarians to see if the generic secret to living a long and healthy life may result in drugs that can prevent the diseases of aging, such as Alzheimers and hea
10、rt disease. It isnt really that obvious, Dr. Thomas Perls, who led the study, said in a telephone interview. It isnt old age that runs in families. Its exceptional old age that runs in families. We think this may be a handful of genes that could be playing really substantial roles in the ability to
11、get to very old age, much of it in good health. Perls team at Harvard University and Beth Israel Deaconess Medical School studied 444 families, including more than 2,000 relatives of people who live to 100. Demographer John Wilmoth of the University of California Berkeley compared this data to the 1
12、900 census and the Social Security Administration database. Female siblings had death rates at all ages at about one-half the national level, they wrote in their report, published in this week issue of the Proceedings of the National Academy of Sciences. Male siblings of centenarians were at least 1
13、7 times as likely to attain age 100 themselves, while female siblings were at least eight times as likely. Perls is not interested in extending life at any cost. WHO WANTS TO GET THAT OLD, ANYWAY? People might think, who wants to live to 100 anyway? because people get the idea that the older you get
14、, the sicker you get. But his study found just the opposite. You can get Alzheimer, stroke, cancer in your 60s and 70s and expect to live another 30,40 years. Earlier work has shown many of these people share similarities in their DNA, especially on chromosome 4. Perls hopes his company, Centageneti
15、x (http:/) can home in on the important genes and perhaps make discoveries that will lead to drugs that can stave off disease. Discovering these genes will lead to understanding the biochemical pathways that those genes affect, he said. My hope is that that would help a lot of other people age more
16、slowly and delay and, my goodness even escape, something like Alzheimer. Which genes you do not have may be as important as those you do, Perls said. For instance, he found the 100-year-olds were very unlikely to have a version of a gene called APOE-4, which is associated with high cholesterol and Alzheimer. Environment did not seem to be too important to those who lived to be 100. Census Bureau data showed they
