Early Maya Culture / A Shortage of Scientists? / Health Sites on the Internet
This is SCIENCE IN THE NEWS, in VOA Special English. I'm Sarah Long. And I'm Bob Doughty. This week ... new thinking about an ancient people.
Concerns about a possible shortage of American scientists.
Some places to go for health information on the Internet.
And, just how much water do we really need to drink?
In Central America, scientists have made some recent discoveries about the ancient Maya people. These findings show that the Maya developed their civilization centuries earlier than experts thought. Three separate teams made the discoveries in the rainforest of Guatemala.
Experts call the time between the year two-fifty and the year nine-hundred the Classic Maya period. It was a period of great civilization. Until now, scientists thought that earlier Maya people were simple farmers. The discoveries show that they used writing, drew pictures and built complex structures sooner than the experts knew.
Scientists have found some things they say are more than two-thousand years old. For example, a team found two masks inside the main pyramid in the city of Cival. These masks are three meters tall. They are cut in the image of a sun god. The Maya used the pyramid as a temple. The masks may have been a part of ceremonies led by a king. Experts from Vanderbilt University in Nashville, Tennessee, made the discovery.
Another Vanderbilt team reported on new research at the city of Cancuen. And scientists from Southern Methodist University in Dallas, Texas, made discoveries at the ancient city of Waka [wah-KAH]. The National Geographic Society supported all the research.
At Waka, scientists found the burial place of a woman they think was a Maya queen. They do not know her name. But they believe she ruled more than one-thousand-two-hundred years ago.
Her bones were lying on a stone table. Many jewels surrounded her remains. The team also found pieces of green stone that appeared to be the remains of the kind of war helmet worn by rulers.
Scientists say the discovery will help then understand how Maya women shared power with men. Not many burial places of important royal women have been found.
Tens of thousands of people may have lived in the ancient city of Waka. Today it is called El Peru.
The Waka project is part of an effort to save an area of rainforest from farming and other illegal activities inside a national park.
Also in northern Guatemala, scientists found a stone showing an eighth-century king playing a game of ball with visiting rulers. It is the third such stone found at the city of Cancuen.
They also found large pieces of stone with writing and pictures of leaders. A Guatemalan expert called it one of the greater masterpieces of Maya art ever discovered in Guatemala.
A new government report warns that the United States may not have enough scientists in the future. The National Science Board says the situation threatens the economic health and security of the country.
The United States is now seventeenth in its share of young people who train in science and engineering. In nineteen-seventy-five, the United States was third among nations in the number of people studying science.
The report says the number of American jobs that require science and engineering will continue to grow. But the number of people prepared for those jobs will not.
Today, thirty-eight percent of all the scientists and engineers in the United States are foreign born. But the National Science Board says the number of people with scientific training who come to the United States will decrease.
One reason is because of limits to entry since the terrorist attacks of September eleventh, two-thousand-one. But there is also intense competition around the world for people with scientific skills.
The National Science Board says that even if action is begun today, the situation will not improve for ten to twenty years. That is because students have to prepare at a young age if they want to become scientists or engineers. They must take the necessary math classes in middle school.
The twenty-four member board governs the National Science Foundation. This independent federal agency advises Congress and the president. The report says the government has a responsibility to support education in science and technology at levels that will appeal to more students.
Americans do still publish almost thirty-three percent of all scientific papers. This is one reason why not all scientists agree about the dangers to the health of American science.
Still, they say schools and scientists themselves should be doing more to get young people to choose science over business or other jobs. For one thing, many older scientists will retire in the next ten years.
You are listening to SCIENCE IN THE NEWS, in VOA Special English.
The National Library of Medicine, near Washington, D.C, is the largest center of medical information in the world. It is part of the National Institutes of Health. Doctors and scientists use this library. So do people from around the world who just want some health information.
The library has a service on the Internet called MedlinePlus. This offers general information about more than six-hundred-fifty diseases and conditions. There is also a medical dictionary, and information about medicines. The Web site is medlineplus.gov. Again, the address is medlineplus dot g-o-v.
The National Library of Medicine also has a Web site for older adults and their families. This service is called N.I.H. Senior Health. The address is nihseniorhealth.gov. The library created this site with the National Institute on Aging. Again, the site is nihseniorhealth, all one word, dot g-o-v.
Many people believe they are supposed to drink eight glasses of water a day, or about two liters. Why? Because that is what they have been told all their life. But a recent report offers some different advice. Experts say people should obey their bodies; they should drink as much water as they feel like drinking.
The report says most healthy people meet their daily needs for liquid by letting thirst be their guide. The report is from the Institute of Medicine, part of the National Academies. This organization provides scientific and technical advice to the government and the public.
The report contains some general suggestions. The experts say women should get about two-point-seven liters of water daily. Men should get about three-point-seven liters. But wait -- in each case, that is more than eight glasses.
There is one important difference. The report does not tell people how many glasses of water to drink. In fact, the experts say it may be impossible to know how many glasses are needed to meet these guidelines. This is because the daily water requirement can include the water content in foods.
People do not get water only by forcing themselves to drink a set number of glasses per day. People also drink fruit juices and sodas and milk. They drink coffee and tea. These all contain water. Yet some also contain caffeine. This causes the body to expel more water. But the writers of the report say this does not mean the body loses too much water.
As you might expect, the Institute of Medicine says people need to drink more water when they are physically active. The same is true of those who live in hot climates. Depending on heat and activity, people could need two times as much water as others do.
All this, however, does not answer one question. No one seems sure why people have the idea that good health requires eight glasses of water daily.
It may have started with a misunderstanding. In nineteen-forty-five, the National Academy of Sciences published some guidelines. Its Food and Nutrition Board said a good amount of water for most adults was two-point-five liters daily. This was based on an average of one milliliter for each calorie of food eaten.
But that was only part of what the board said. It also said that most of this amount is contained in prepared foods.
SCIENCE IN THE NEWS was written by Nancy Steinbach and Jerilyn Watson. Cynthia Kirk was our producer. This is Sarah Long. And this is Bob Doughty. Listen again next week for more news about science, in Special English, on the Voice of America.