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From VOA Learning English, this is SCIENCE IN THE NEWS in Special English. I’m Bob Doughty.

And I’m Faith Lapidus. Today, we tell about an effort to require food producers to identify genetically engineered foods. We also tell about a study of wild tigers in Nepal. And we tell about a newly identified animal species.

Food activists say everyone has a right to know what they are eating. A few weeks ago we reported on an effort by food activists in the American state of California. They wanted California voters to approve a requirement that food manufacturers identify food made from genetically engineered crops.

In September, studies of likely voters had shown most people agreed with the proposed law. But on election-day, fifty-three percent of voters rejected it. Only forty-seven percent supported the call for labels to identify foods containing genetically modified organisms or GMOs. The measure would have identified such foods, but not banned them.

Food activists say money heavily influenced the election results. They say some food manufacturers gave false information to voters. They also say local newspapers were influenced by manufacturers that buy large amounts of advertising.

Both sides fought to win support from the public. Here is part of a television ad paid for by opponents of the proposal.

“They’re at it again. Special interests pushing a proposition that would create more government red tape, more government law suits and higher costs. This time it’s ‘Prop 37’ – a food labeling scheme written by trial lawyers to benefit trial lawyers. Thirty-seven would ban thousands of common food products in California unless they are specially relabeled to meet complex, new requirements and restrictions that would only exist in our state.”

Supporters of the measure included cooks from television food shows and even movie actors.

“What makes you think you have the right to know? I don’t think you have the right to know. Who do you think you are? Do you want the truth? You can’t handle the truth. Your puny little head would explode. They are just some things you shouldn’t know about, like what’s in your food. Why would you want to know what’s in your food? You shouldn’t know whether your food is genetically modified. It’s kind of none of your business.”

GMOs have been part of the food supply in the United States since nineteen eighty-seven, when genetically engineered tomatoes were first sold. Genetic engineering is the technology of changing the genes of living things. Scientists use special technologies to place genetic material from one species into another.

Some food crops now contain genes from other plants or even genes from fish or animals. Now almost all cooking oils include GMOs. One expert estimates that about seventy percent of food sold in the United States contains one or more GMOs.

The United States is not among the more than sixty countries that require labels to identify whether a food has been genetically modified. Japan requires such labeling if more than five percent of a food or food product contains GMOs. In India, lawmakers are working on a plan that would require labeling for even smaller amounts of GMOs.

Opponents of the California plan argued that food would cost more if manufacturers were required to label foods that have genetically modified organisms. Food activists say existing label laws have not increased the price of food. They say the labels give buyers important information. Some manufacturers already label their products so buyers will know the food does not contain a GMO.

Scientists have high hopes for the healthful effects of genetically engineered food. However, food activists continue to call for more testing. Until the long term safety of eating GMOs is confirmed, they want people to make informed choices about what they buy and eat.

An example of this kind of dispute was in the news recently. Working together, American and Chinese scientists genetically engineered rice to include beta carotene, a substance that helps humans make vitamin A. The researchers found that Chinese children who ate the modified rice increased their levels of vitamin A. Children whose food does not provide enough Vitamin A can go blind and even die.

Scientists are excited about the positive effects of the genetically modified rice. However, the environmental group Greenpeace has criticized the experiment. It says the safety of genetically-modified foods over time has never been confirmed.

Greenpeace and natural food activists say they want the government, and not food manufacturers, to test the safety of GMOs. They point to the history of tobacco companies in the United States. After a series of cases, courts found that tobacco companies had lied about the cancer risk of cigarettes for many years.

The dispute over GMOs has divided organic farmers and food markets. Farms and food producers must earn the right to claim their food is organic or free of chemicals. The largest organic food businesses object to labeling GMOs. They say a food can be natural and organic even if it has been genetically engineered.

Activists say testing is necessary because a food cannot be considered safe until all the risks are understood. Manufacturers base their safety claims on a ninety-day testing period. Activists say the tests are not long enough to show all the possible effects.

For years, wildlife experts have said that tigers avoid living close to people. But a new study disputes the belief that these animals need lots of people-free space.

The study appeared in the Proceedings of the National Academy of Sciences. The findings are considered important because there are only about three thousand two hundred wild tigers in the world. That is a ninety-seven percent decrease since the start of the twentieth century. The drop has been blamed on the ever-rising human population, agriculture and the development of areas where the big cats live.

The study took place in and around the Chitwan National Park in Nepal. The park lies near the Himalayan Mountains. The area is home to about one hundred twenty tigers.

Neil Carter is a graduate student at Michigan State University. His goal was to study how the tigers reacted to people who visited the Chitwan National Park and local villagers. He placed camera traps in eighty different places. He says the images they captured showed intense activity inside and outside the park.

“Tigers were everywhere, people were everywhere. And obviously they could not have been in the exact same places at the same time because there will be reports of all kinds of conflicts, left and right.”

Normally, tigers move around at any time of day or night. But the researcher says the images show that most of the big cats were more active at night. He says they even walked outside the park on the same dirt roads and narrow paths used by people.

Neil Carter says he was surprised to find that the tigers changed the timing of their activities, but not place. And he notes a good reason. The animals that tigers hunt for food were in that space.

“There was no relationship between the number of vehicles or people or even different types of people. Tigers were there. They were everywhere. They were widespread and ubiquitous and also the prey, their prey, was really abundant. And so that, I think is really sort of the critical link.”

Tigers, he says, are not going to leave an area that has their food.

Neil Carter says the study results could change wildlife management. He notes that people now live in about eighty percent of tiger habitat. He says the study shows promise that humans and wildlife can occupy the same environment. But he adds that more work is needed to understand the complex connection between the two worlds.

Finally, an Amazonian glass frog called Centrolene sabini gained worldwide attention earlier this year. It became the seven thousandth amphibian to be added to the AmphibiaWeb catalog of new amphibian species.

The brightly colored green frog was found at Manu National Park in the Peruvian Amazon. It is one of more than three thousand amphibians to be added to the new species list in the past twenty-five years.

The AmphibiaWeb project was the idea of scientists at the University of California, in Berkeley, California. They launched the AmphibiaWeb project twelve years ago in an effort to bring attention to shrinking amphibian populations. The scientists found that amphibians are doing well in many parts of the world. They also learned that many amphibians have yet to be discovered.

David Wake is professor emeritus of integrative biology at UCB. He started the AmphibiaWeb project. When the project first began, there were only about five thousand recognized amphibian species. That number had increased to more than seven thousand twenty by August of this year.

Professor Wake says new amphibian species are being added to the scientific literature nearly every two and a half days. More than one hundred new amphibian species have been added to the database this year alone.

There are three categories of amphibians. Frogs and toads represent the largest group, with more than six thousand documented. Newts and salamanders are the next largest group, with more than six hundred known species. These creatures are often confused with lizards because they look a lot alike.

Caecilians represent the smallest group of amphibians. These legless, tailless amphibians look a lot like snakes or earthworms. AmphibiaWeb hopes to document every species of amphibian in the world.

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（来源：VOA 编辑：Julie）