Australia's koalas could die out within 30 years unless immediate action is taken to stop the losing in population, according to researchers. They say development, climate change and bushfires have all combined to reduce the number of wild koalas sharply.

    The Australian Koala Foundation said a recent survey showed the population could have dropped by more than half in the past six years. The number of koalas was once estimated to be more than 100,000, but now is as few as 43,000.

    The foundation collected field data from 1,800 sites and 80,000 trees to calculate the numbers. In one area in northern Queensland estimated to have 20,000 koalas a decade ago, a team of eight people could not find a single animal in four days of searching.

    The foundation said besides problems caused by cutting down forests, hotter and drier conditions because of global warming had reduced the nutritional value of their main food, eucalyptus (桉树) leaves, leading to poor nutrition for them. Koalas, which live in the forests in Australia's east and south, are very picky about what types of the leaves they eat.

    Foundation chief Deborah Tabart said: “The koalas are missing everywhere we look. It's really no tree, no me. If you keep cutting down trees you don't have any koalas.”She is hoping the new figures will persuade the government's Threatened Species Steering Committee (TSSC) to list the koala as threatened. But committee chairman Bob Beeton said a decision was not likely recently and the koala's status as one of the country's favorite animals would not be a factor. “There's a number of species which are attractive and people have special feelings towards them. We don't consider that,” Mr Beeton said.

    A “lost tribe” that reached America from Australia may have been the first Native Americans, according to a new theory.

    If proved by DNA evidence, the theory will break long established beliefs about the southerly migration of people who entered America across the Bering Strait, found it empty and occupied it.

    On this theory rests the belief of Native Americans to have been the first true Americans. They would be classified to the ranks of escapee, beaten to the New World by Aboriginals (土著人) in boats.

    To a European, this may seem like an academic argument, but to Americans it is a philosophical question about identity, Silvia Gonzales, of Liverpool University said.

    Her claims are based on skeletons found in the California Peninsula of Mexico that have skulls quite unlike the broad Mongolian features of Native Americans. These narrow-skulled people have more in common with southern Asians, Aboriginal Australians and people of the South Pacific Region.

    The bones, stored at the National Museum of Anthropology (人类学) in Mexico City, have been carbon-dated and one is 12,700 years old, which places it several thousand years before the arrival of people from the North. “We think there were several migration waves into the Americas at different times by different human groups,” Dr. Gonzales said. “The timing, route and point of origin of the first colonization of the Americas remains a most contentious topic in human evolution.”

    But comparisons based on skull shape are not considered conclusive by anthropologists, so a team of Mexican and British scientists, backed by the Natural Environment Research Council, has also attempted to take out DNA from the bones. Dr. Gonzales declined yesterday to say exactly what the results were, as they need to be checked, but indicated that they were consistent (一致) with an Australian origin.

    It is easier to float in the ocean than it is to float in a swimming pool.Do you know why?

    Ocean water is full of salt--and salt water can hold up more weight than fresh water.See for yourself!

You will Need:

3 cups of warm water

Measuring cup(量杯)

Wide-mouthed jar

Salt

Spoon

Raw(生的)potato

You Will Do:

⒈Pour 1.5cups of warm water into the jar.

⒉Add 1/3 cup of salt.

⒊Stir(搅拌) until the salt is completely dissolved.

⒋Add another 1.5 cups of water.Pour it slowly over the back of the spoon into the jar so that the two liquids will not mix together.

⒌Gently place the potato into the jar.Do not drop it.

    What Will Happen:

    The potato will sink--but only halfway!

    Why?

    Salt water is heavier than fresh water,so it will stay on the bottom.The fresh water will remain on top.

    The potato is heavier than the fresh water,but it is lighter than the salt water.That is why the potato will sink halfway down.

阅读下列短文，从每题所给的四个选项 （A 、B 、C  和 D ）中，选出最佳选项。

    Christmastime in the city brings forests of trees already cut and waiting to be sold. But some people like to drive to tree farms. Others wait for their trees to come to them. They order one from the pages of a catalog or on the Internet. Some say the easiest thing of all is to buy a man­made tree with Christmas lights already on it. No falling needles to have to clean up.

    The National Christmas Tree Association says 33,000,000 real trees were sold last year, compared to 9,000,000 man­made ones. Man­made trees generally cost more, but they can be reused. Most natural trees are cut up and recycled, but some people buy trees that can be planted.

    Most Christmas trees are now grown on farms instead of in forests. Twenty-one thousand tree farmers in the United States grow Christmas trees on more than 180,000 hectares. Oregon was the leading producer last year.

    Twenty-two percent of people who bought real trees last year chose them at a farm. Two percent of those people cut the trees themselves. The next most popular places were big stores like Walmart and Home Depot. Groups like the Boy Scouts also sell Christmas trees. But some people pay nothing for theirs. They steal it.

    Cornell University in Ithaca, New York, has many pretty evergreens. Some years ago, a university worker found a way to keep them there. A month before Christmas, workers treated them with “pink ugly mix”. It contains water and red food colour. The bright colour starts to disappear after about a month. It can take longer, however. Cornell decided not to use the mix this year, but the idea has spread.

    Now women are free to enter any career that attracts them, and working can bring them pride, confidence and independence. Working women make up nearly half of the U.S. workforce, and 51 percent of professional workers, like doctors, lawyers, nurses and accountants, are female. While climbing the career ladder can be rewarding, it often comes with one big disadvantage: weight gain!

    New research published this week in the International Journal of Obesity shows that working women are more likely to be overweight, and the more you work, the more pounds you're likely to pile on. Like many women, I work... a lot! As a self-employed nutrition communications specialist, I sit at my desk, in front of a computer, for hours on end. Sitting alone is one of the worst things you can do for your health, and it's directly linked to being overweight and increased fatness, so the fact that women in the workforce gain weight isn't that surprising. If you work, you have less time to move around. Obesity researchers are revealing many other ways that employment is harmful to your diet and waistline(腰围).

    In the International Journal of Obesity study, some 9,276 Australian women aged 45-50 had their body weight and employment status monitored for two years. Results? Those who worked more than 35 hours were likely to gain weight compared to those who worked fewer hours or were out of the workforce. What's more, the more hours a woman worked in a week, the more weight she gained.

    The authors of the Australian study attribute weight gain among working women to inactivity, lack of time for food preparation, more use of prepared foods, high levels of stress, lack of sleep and consuming more alcohol. I'll also add in travel, meals eaten out and working at night as other factors that I can find to make balancing work with a healthy diet a challenge.

    Note taking

    Note taking as an accommodation is available only to students who have documented disabilities and are registered with Queen's University Accessibility Service(QSAS). Note taking is approved for students with disability-related functional limitations that makes it difficult for them to access academic information presented in class.

    There is a wide range of reasons why students may require note taking as an accommodation, including students with:

    •hearing loss, who may have difficulties hearing the instructor while writing notes at the same time

    •vision loss, who may have difficulties seeing information presented on overhead screens

    •mental health conditions or attention-related disabilities, who may have difficulties attending to orally-presented information while taking notes

    •learning disabilities, who may have difficulties recording notes when information is presented orally

    •physical disabilities, who may have motor or pain related difficulties

    Accessibility advisers consider a student's description of their need for note taking along with information contained in their disability documentation and the type of course in approving note taking as a formal accommodation.

    Online Note Taking Portal(门户网站)

    QSAS is in charge of the exchange of notes taken by student volunteer note takers and students registered with QSAS via our secure online note taking portal.

    The pages in this section provide information for students with disabilities, volunteer note takers and instructors on requesting note takers, signing up to be a volunteer note taker and assisting QSAS with recruiting volunteer note takers.

    If you are a student seeking note taking accommodation please click here to read the Starting Your Accommodation information.