Why play games? Because they are fun, and a lot more besides. Following the rules… planning your next move…acting as a team member…These are all “game” ideas that you will come across throughout your life.

    Think about some of the games you played as a young child, such as rope-jumping and hide-and-seek. Such games are entertaining and fun. But perhaps more importantly, they translate life into exciting dramas that teach children some of the basic rules they will be expected to follow the rest of their lives, such an taking turns and cooperating（合作）.

    Many children's games have a practical side. Children around the world play games that prepare them for work they will do as grown-ups. For instance, some Saudi Arabian children play a game called bones，which sharpens the hand-eye coordination（协调）needed in hunting.

    Many sports encourage national or local pride. The most famous games of all, the Olympic Games, bring athletes from around the world together to take part in friendly competition. People who watch the event wave flags, knowing that a gold medal is a win for an entire country, not just the athlete who earned it. For countries experiencing natural disasters or war, an Olympic win can mean so much.

    Sports are also an event that unites people. Soccer is the most popular sport in the world. People on all continents play it—some for fun and some for a living. Nicolette Iribarne, a Californian soccer player, has discovered a way to spread hope through soccer. He created a foundation to provide poor children with not only soccer balls but also a promising future.

    Next time you play your favorite game or sport, think about why you enjoy it, what skills are needed, and whether these skills will help you in other aspects of your life.

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    Modern lifestyles are generally quite different from those of our hunter-gatherer ancestors, a fact that some claim as the cause of the current rise in global obesity, but new results published July 25 in the open access journal PLOS ONE find that there is no difference between the energy expenditure(耗费) of modern hunter-gatherers and Westerners, casting doubt on this theory.

    The research team behind the study, led by Herman Pontzer of Hunter College in New York City, along with David Raichlen of the University of Arizona and Brian M. Wood of Stanford measured daily energy expenditure among the Hadza, a population of traditional hunter-gatherers living in the open Savannah of northern Tanzania. Despite spending their days hiking long distances to seek for wild plants and game, the Hadza burned no more calories each day than adults in the U.S. and Europe. The team ran several analyses accounting for the effects of body weight, body fat percentage, age, and gender. In all analyses, daily energy expenditure among the Hadza hunter-gatherers was indistinguishable(难以区分的) from that of Westerners. The study was the first to measure energy expenditure in hunter-gatherers directly; previous studies had relied entirely on estimates.

    These findings overturn the long-held assumption that our hunter-gatherer ancestors expended more energy than modern populations, and challenge the view that obesity in Western populations results from decreased energy expenditure. Instead, the similarity in daily energy expenditure across a broad range of lifestyles suggests that habitual metabolic(新陈代谢的) rates are relatively constant among human populations. This in turn supports the view that the current rise in obesity is due to increased food consumption, not decreased energy expenditure. It means we have more to learn about human physiology(生理学) and health, particularly in non-Western settings.

    "These results highlight the complexity of energy expenditure. It's not simply a function of physical activity," says Pontzer.” Our metabolic rates may be more a reflection of our shared evolutionary past than our diverse modern lifestyles."

    Four of the World's Best Futurists(未来学家)

    Kevin Kelly

    Kevin Kelly is an author. His 1994 publication, Out of Control, discusses a future where machines and systems are so complex as to be indistinguished(难区分的) from living things.

    His latest book What Technology Wants suggests that technology is not just a mixture of wires and metals but a living thing that has its own need. The book looks out through the eyes of this global technological system to discover what it wants.

    Dr Michio Kaku

    Dr Michio Kaku is a professor of theoretical physics at the City of New York and author of The Future of the Mind and Physics of the Future.

    In The Future of the Mind , he explores the frontier of neuroscience. He predicts that one day we will be able to upload the human brain into a computer. In Physics of the Future, he predicts that glasses and contact lenses will be connected to the Internet and cars will become driverless with the power of the GPS system.

    David Brin

    Science fiction author and scientist, David Brin has received awards. In 1998, he won the Freedom of Speech Award for The Transparence Society. The book concerns threats to personal affairs and openness in the information age. In a world where the police monitor public places 24 hours a day with cameras and some credit companies can sell people's financial details to anyone willing to pay, Brin warns that surveillance(监控) technology will be used by too few people in the future. He argues that the tables should be turned and the public should have access to information like who is buying financial details from credit companies.

    Dr Ray Kurzweil

    Dr Ray Kurzweil is the main inventor of the first print-to-speech reading machine for the blind. He is the director of artificial intelligence development at Google.

    Over the past 25 years, a number of his predictions have come true. In 1990, he predicted a computer would defeat a human at chess by 1998.He predicts that by the 2020s, most diseases will go away and self-driving cars begin to take over the roads.

    Forests are always losers at the Olympics, and that's unlikely to change anytime soon.

    For the winter games in PyeongChang, South Korea, virgin forest was destroyed on Mount Gariwang to accommodate ski runs. For the 2022 Winter Olympics in Beijing, a ski run is set to wipe out part of the Songshan National Nature Reserve And let's not forget the 240 acres of Atlantic Forest that were leveled for the 2016 games in Rio de Janeiro to make way for a golf course.

    For the upcoming Tokyo games, environmental and human rights advocates have been raising alarms about the use of tropical wood to build the New National Stadium. Activists have fought against such environmental destruction. The damage is often permanent, threatens endangered plants and animals and, in some cases, causes conflicts with native people But frequently the country's organizing committee, and the International Olympic Committee (IOC) have found ways to make it reasonable—despite a paragraph in the Olympic Charter that states that the IOC's role is to "encourage and support a responsible concern for environmental issues."

    As it stands now. the IOC has little authority over a city's local organizing committee, which finally plans the event, Chappelet, professor of public management at the University of Lausanne, told Earther. "Even if the IOC is dissatisfied with the way host cities have prepared for the games, they have no built-in systems to supervise (监督) them so that they strictly follow the Olympic Charter. The only thing they can do if they're not happy is to withdraw the right to organize the game. But the IOC could include more enforcement (执行) systems into the contract (合同) they make with the host city, he added. That contract must be signed and obeyed by everyone. Those who break it could be fined.

    Boykoff, the author of several books on the Olympics, suggested a similar solution. "The IOC could insist that host cities prioritize their ecological promises, but instead they look the other way, time and time again," he said.

    When you eat fish, you probably eat it off a plate, using a fork. Well, the dolphins in Shark Bay, Australia, eat their fish from conch（海螺）shells!

    Scientists have found some of these bottlenose dolphins（宽吻海豚）using their large beaks to trap fish in shells underwater. Then, carrying the shells to the surface, they shake out the fish into their mouths and eat them. Clearly, using the conch shells allows the dolphins to catch more fish than they would be able to without such a tool. The technique has been called "conching".

    Researchers noticed dolphins engaging in the behavior a handful of times from 2007 to 2009. This dolphin trend seemed to become popular.

    Simon Allen, a scientist, was surprised to see the conching technique spreading. "In the lasts four months alone, the research team have seen and photographed the behavior no less than six times, possibly even seven," he said in a press release. He thinks the dolphins may be learning conching from one another.

    Dolphins are known to be highly intelligent. The size of their brain is large in proportion（比例）to their body size. Compared with other animals, they have highly developed communication and social skills. This species of dolphin also uses other tools. They will break off pieces of sponges that grow in the ocean, for example, and use them to cover their beaks. This allows them to search for food on the ocean floor without hurting their noses.

    Scientists are going to keep trying to catch the dolphins in the act of conching. They hope to see evidence of the dolphins teaching one another the technique. They also want to know how the dolphins get fish in the conch shell. Do they push the fish into the shell with their beaks? Or do they chase the fish into the shell before carrying them up to eat?

    However they do it, Allen believes these dolphins to be particularly clever. "I wouldn't be too surprised to find such cunning ploys being adopted by Shark Bay's bottlenose dolphins," he said in statement.

    Do women make BETTER astronauts? Russia locks an all-female crew in space simulator (太空模拟器) for eight days to find out. Six Russian women have been sent into a spaceship to begin a unique experiment testing how an all- female crew would relate to others on a trip to the Moon and back.

    "It's interesting for us to see what is special about the way a female crew communicates," said Sergei Ponomaryov, the experiment's leader." it will be particularly interesting in terms of psychology," said the institute's director Igor Ushakov. "I'd like to wish you a lack of conflicts, even though they say that in one kitchen, two housewives find it hard to live together," he added.

    The volunteers include scientific researchers, a doctor and a psychologist. The test period simulates (模仿) a flight to the Moon and back, with the women carrying out 10 experiments covering psychology and human biology. Russia sent the first woman into space, Valentina Tereshkova, in 1963 but has fallen behind since. Last year, it sent its fourth female astronaut into space, Yelena Serova. Serava complained of a great deal of media interest in how she would wash her hair aboard the International Space Station, pointing out that male astronauts did not face the same line of questioning.

    The women found themselves fielding questions at a press conference about how they would act without men or makeup for eight days, "We are very beautiful without makeup," said participant Darya Komissarova. Her colleague Anna Kussmaul was more direct: "We are doing work. When you're doing your work, you don't think about men and women." They plan to spend their 11/2 hours per day of free time watching films, reading and playing board games. Team leader Yelena Luchnitskaya said she expected the women to deal with any conflict.