“Plants were expected to get larger with increased carbon dioxide in atmosphere, but  changes in temperature, humidity and nutrient availability seem to trumped the benefits of  increased carbon dioxide，” said researchers from the National University of Singapore.

    45 percent of the species studied now reach smaller adult sizes than they did in the past. The  researchers pointed out that warmer temperatures and changing habitats, caused by climate  change, are possible reasons for shrinking creatures.

     “We do not yet know the mechanisms involved, or why some organism are getting smaller while others are unaffected，” the researchers said. “Until we understand more, we could be risking negative consequences that we can't yet quantify.”

    The change was big in cold­blooded animals. Only two decades of warmer temperatures were enough to make reptiles smaller. An increase of 1 degree centigrade caused nearly a 10 percent increase in metabolism (新陈代谢). Greater use of energy resulted in tiny tortoises and little lizards. Fish are smaller now too. Though overfishing has played a part in reducing numbers, experiments show that warmer temperatures also stop fish growth. There is a recent report on warmer temperatures' negative effects on plankton, the base of the marine ecosystem.

    Warm­blooded animals weren't immune from the size change caused by climate change. Many birds are now smaller. Mammals have been miniaturized too. Soay sheep are thinner. Red deer are weaker. And polar bears are smaller, compared with historical records.

    This is not the first time this has happened in Earth's history. 55 million years ago, a warming event similar to the current climate change caused bees, spiders and ants to shrink by 50 to 75 percent over several thousand years. That event happened over a long time than the current climate change.

    The speed of modern climate change could mean organisms may not respond or adapt quickly enough, especially those with long generation times. So, it is likely that more negative influences of climate change will be shown in future.

    The world's population is more mobile (移动的)today than ever before. In 2010, more than 200 million people left their home countries to live in a new country. This is about 3 percent of the total world population. Some experts believe that number will swell to 400 million by 2050. Rates of immigration have remained strong for the last 300 years, but patterns of immigration have changed since World War II. The backgrounds and experiences of today's immigrants are different from those of the typical European immigrant of the nineteenth and early twentieth centuries. Contemporary immigrants range from unskilled laborers to highly skilled professionals, and they come from and go to countries all over the world.

    In the nineteenth century and until World War II, immigration was primarily in one direction- from the Old World to the New World. This is no longer the case. Countries such as Russia and China, which have long been, and continue to be, significant source countries, are now also destination countries. There is also considerable mobility inside regions, such as from one European country to another, or among the countries of the former Soviet Union.

    In spite of such differences, the push and pull factors for immigration remain essentially the same as they were 100 years ago. Most people move to another country because they want a better life. For the majority of immigrants, this means better economic conditions. As in past generations, a labor shortage in one country often draws workers from another country, especially if wages are significantly higher. In some small countries, for example, Qatar, United Arab Emirates, and Kuwait, there are more jobs than citizens. The demand for labor is so high that the majority of the population consists of foreign-born workers, ranging from highly skilled engineers and financial experts to domestic and construction workers.

    In traditional destination countries, such as the United States, however, labor needs have changed. Today, although there is still demand for unskilled labor, there is increasing demand for people with a high level of skill and education. The need for less skilled labor has shifted to other countries. As work on farms and in industry in the United States and Canada once drew workers from all over the world, now work in factories in Taiwan and south Korea attracts workers from Vietnam, the Philippines, and Cambodia.

    Most global immigration is legal: however, a large number of people also move across national borders illegally in pursuit of(寻找) employment. Experts estimate that about 15 to 20 percent of immigrants worldwide are in their new countries illegally. The United States has the largest number of these immigrants, followed by South Africa, with significant numbers also in Northern and Western Europe and Mexico. These immigrants face particular challenges because they often must hide from the authorities who might deport them back to their home countries. Their illegal status also means that employers may take advantage of them by forcing them to work longer hours and paying them less than the legal minimum wage.

    Although economics remains the most important motivation in all forms of immigrant, other factors are also important. Some people decide to leave their home countries because their actions or political beliefs make it dangerous for them to remain. Others choose to leave because their home country has become too dangerous and unstable, often because of war or political unrest. They wish to find a place that is secure for themselves and their families. Education is also a significant factor for many modern immigrants. They want to raise their children in a place where they can get a good education, which, in turn, they hope will provide them with better prospects for the future. Finally, family and community ties also play a role in immigration decisions. As in the past, once a group of people from one country establishes a community in a new country, more people from that country is likely to follow.

    The pattern, direction, and rate of immigration may change as the global economy changes. However, as long as life in a new country is more attractive than life in the old country, immigration will continue.

    At the age of seven, while his friends were spending their allowances on candy and toys, Jose Adolfo Quisocola, from Peru, came up with the creative idea of an eco-bank, which allows kids of all ages to become economically independent and financially wise while also helping the environment.

    Established in 2012, The Bartselana Student Bank is the world's first cooperative bank for kids. Whoever wants to join has to bring in at least 5 kilograms(11 pounds) of solid waste(paper or plastic) and establish a savings goal. Once accepted, all bank “partners” are required to deposit at least one additional kilogram(2.2 pounds) of recyclables on a monthly basis and obey other requirements, such as attending financial education and environmental management workshops. The waste accumulated is sold to local recycling companies, who, thanks to some clever negotiation by Jose, pay a higher-than-market rate for everything brought in by Bartselana Student Bank members. The funds received are placed in the individual's account where they collect until his／her savings goal is reached. The account holder can then withdraw his／her money, or choose to leave it and continue to grow for a bigger target.

    “At the beginning, my teachers thought I was crazy or that a child could not undertake this type of project, ” Jose recalls. “They did not understand that we are not the future of the country but its present. Luckily, I had the support of the school principal and an assistant in my classroom.”

    The youngster's persistence paid off. Today, the eco-bank, which now has the support of several local institutions, has ten educational centers and begins accepting applications from kids all across Peru. On November 20, 2018, the young boy was awarded the famous Children's Climate Prize (CCP). “Jose's eco-bank is a brilliant way of linking economy and climate impact, both in thought and practice. The potential impact is amazing,” a judge said.

    Hopefully, Jose's success will inspire more kids and adults to come up with new ideas that create value while helping the environment. As the boy says,” Together we can change the world…we just need an opportunity…”

    Unbelievable Stories of Animals Acting Just Like Humans

    Horses are picky eaters

    Horses have an even better sense of smell than humans do. When horses raise their noses and open their nostrils (鼻孔) , their nervous system allows them to sense smells we can't sense. This might explain why they refuse dirty water and carefully mover around meadows, eating only the tastiest grasses, experts say.

    Whale says thanks

    In 2011, a whale expert spotted a humpback whale trapped in a fishing net and spent an hour freeing it. Afterward, in an hour-long display of thanks, the whale swam near their boat and leaped into the air about 40 times.

    Pandas like to be naughty

    Is there anything more lovely than a baby panda, except maybe a human baby? In fact, baby pandas sometimes behave like human babies. They sleep in the same positions and value their thumbs. Pandas are shy by nature for its shy behaviors such as covering its face with a paw of ducking its head when confronted by a stranger.

    A cat honors its owner

    Paper towels, and a plastic cup are just a few of the gifts that Toldo, a devoted three-year-old gray-and-white cat, has placed on his former owner Iozzelli Renzo's grave every day since the man died in September 2011. Renzo adopted Toldo from a shelter when the cat was three months old, and the two formed an inseparable bond. After Renzo passed away. Toldo followed the coffin to the cemetery, and now “stands guard” at the grave for hours at a time.

The Rapid Rise and Fall of Robot Babysitters

    During the winter of 2017, an 18-year old college student named Canon Reeves spent much of his time trailing a knee-high robot around Fayetteville, Arkansas, as it delivered Amazon packages to students. The robot, created by a start-up called Starship Technologies in 2014, is basically a cooler on wheels; it uses radars, sensors, and nine cameras to make deliveries. Reeves's job was to monitor how it handled various grounds, field comments from the public, and press the off switch if necessary. He said, "People would also ask if it could deliver beer." It couldn't.

    Broadly speaking, jobs of caring for robots fall under the umbrella of careers in automation, which include maintenance, engineering and programming. The demand for people with this skill set is considerable, with 20 million to 50 million new jobs to be expected in this category by 2030, according to the Mckinsey Global Institute. In the year that ended in June 2018, Indeed.com had almost three times the number of positions on the recruitment committee that ended in June 2016.

    Over the last year, a 34-year-old businessman named David Rodriguez spent hundreds of hours following a machine called the KiwiBot around UC Berkeley's campus while it delivered Red bull and other drinks to students. To retrieve (检索) orders, the app encourages students to give the robot a wave; the robot's digital eyes will roll depending on its mood. Rodriguez, who heads business development for the start-up, was tasked, early on, with monitoring the KiwiBot for problems – even carrying it, should the motors fail. Since April 2018, though, the KiwiBot has largely been left unattended, and the majority of human interactions involve technical checks and loading food into the robot. To eliminate the boring work, the team is developing a restaurant robot to collect and load orders – which could happen in 2020. However, Rodriguez assured me that his staff won't be out of work. Everyone holds double roles in the company. Greater robot self-governing just means employees will shift their focus to accounting, engineering, and design.

    Mckinsey estimates that millions of jobs globally could be lost to automation by 2030. "A huge number of jobs will be produced as autonomous vehicles are released into the environment," Ramsey said. In 2016, Bosch started training students from Schoolcraft College, a community college in Michigan, in autonomous-vehicle repair; Toyota has trained students in maintenance as well. "We might even see a return to low-level jobs where people come and fuel the car for you," Ramsey said. "Until we can wirelessly charge, someone needs to refuel them." The hardest-to-automate industries, as it happens, are the ones that require looking after humans, such as childcare, education and health care. Robot babysitters might feel like they have scored the job of the future, but in fact, they might be better positioned.

Land of fire and ice: Iceland

    Join an unforgettable tour of Iceland's splendid landscapes, timed to arrange four days filled with volcanic and geological adventure, and evening opportunities to see the Aurora Borealis.

    Day 1: Vatnajokull Glacier (冰川)

    Today you'll take a walk on Europe's biggest ice cap-Vatnajokull-which has around 30 glaciers flowing out from it. No experience is necessary to take part in the hike. It's discouraging to think that the glacier is retreating due to rising world temperatures, and in future years the glacier may be gone. If you prefer a relaxing morning you can explore the surroundings of the farm stay and head to the Thorbergur Centre.

    Day 2: Secret lagoon (泻湖) and Reykjavik

    This morning we make our way to the Lava Centre which is an interactive, high-tech educational exhibition describing volcanic activity, earthquakes and the creation of Iceland over millions of years. After our visit, we will continue to the Secret Lagoon natural hot springs, located in the small village called Fludir, giving you the opportunity to relax in the warm waters before travelling to Reykjavik.

    Day 3: Reykjanes peninsula (半岛)

    Head out to the Reykjanes Peninsula. It is a land-born highly volcanic counterpart of the Mid-Atlantic Spreading Ridge where two tectonic plates part at an average rate of 2.0-2.5 cm/yr. Four volcanic systems and fissure (裂缝) groups line the peninsula from SW to NE. They contain open fissures, normal faults, high-temperature fields and volcanic fissures.

    Day 4: Depart Reykjavik

    Today is departure day and time to say "sjaumst". Your group departure transfer will take you to the airport for your flight home.