Oh, the places you'll go!

    When it comes to habitat, human beings are creatures of habit. It has been known for a long time that, whether his habitat is a village, a city or, for real globe-trotters (周游世界者), the planet itself, an individual person generally visits the same places regularly. The details, though, have been surprisingly obscure. Now, thanks to an analysis of data collected from 40,000 smartphone users around the world, a new property of humanity's locomotive (移动的) habits has been revealed.

    It turns out that someone's "location capacity", the number of places which he or she visits regularly, remains constant over periods of months and years. What constitutes a "place" depends on what distance between two places makes them separate. But analyzing movement patterns helps illuminate the distinction and the researchers found that the average location capacity was 25. If a new location does make its way into the set of places an individual tends to visit, an old one drops out in response. People do not, in other words, gather places like collector cards. Rather, they cycle through them. Their geographical behavior is limited and predictable, not fancy-free.

    The study demonstrating this, just published in Nature Human Behavior, does not offer any explanation for the limited location capacity it measures. But a statistical analysis carried out by the authors shows that it cannot be explained solely by constraints on time. Some other factor is at work. One of the researchers draws an analogy. He suggests that people's cognitive capacity limits the number of places they can visit routinely, just as it limits the number of other people an individual can routinely socialize with. That socialization figure, about 150 for most people, is known as the Dunbar number, after its discoverer, Robin Dunbar.

    Lehmann says his group is now in search of similar data from other primates (灵长目动物), in an attempt to work out where human patterns of mobility have their roots. For those, though, they will have to rely on old-fashioned methods of zoological observation unless they can work out a way to get chimpanzees to carry smartphones.

    When John was growing up, other kids felt sorry for him. His parents always had him weeding the garden, carrying out the garbage and delivering newspapers. But when John reached adulthood, he was better off than his childhood playmates. He had more job satisfaction, a better marriage and was healthier. Most of all, he was happier. Far happier.

    These are the findings of a 40-year study that followed the lives of 456 teenage boys from Boston. The study showed that those who had worked as boys enjoyed happier and more productive lives than those who had not. "Boys who worked in the home or community gained competence（能力）and came to feel they were worthwhile members of society, " said George Vaillant, the psychologist（心理学家）who made the discovery. "And because they felt good about themselves, others felt good about them."

    Vaillant's study followed these males in great detail. Interviews were repeated at ages 25, 31and 47. Under Vaillant, the researchers compared the men's mental-health scores with their boyhood-activity scores. Points were awarded for part-time jobs, housework, effort in school, and ability to deal with problems.

    The link between what the men had done as boys and how they turned out as adults was surprisingly sharp. Those who had done the most boyhood activities were twice as likely to have warm relations with a wide variety of people, five times as likely to be well paid and 16 times less likely to have been unemployed. The researchers also found that IQ and family social and economic class made no real difference in how the boys turned out.

    Working—at any age—is important. Childhood activities help a child develop responsibility, independence, confidence and competence—the underpinnings（基础）of emotional health. They also help him understand that people must cooperate and work toward common goals. The most competent adults are those who know how to do this. Yet work isn't everything. As Tolstoy once said, "One can live magnificently in this world if one knows how to work and how to love, to work for the person one loves and to love one's work."

    Have you ever spent an afternoon in the backyard, maybe grilling or enjoying a basketball game, when suddenly you notice that everything goes quiet? There is an old phrase "calm before the storm"， often used in a situation—a quiet period just before a great activity or excitement. According to our own experience, we know there is actually calm before the storm. But what causes this calm? And is it always calm before the storm? Let's hear what scientists have to say.

    A period of calm happens in a particular kind of storm, the simplest kind of storm—a single－cell thunderstorm. In this type of thunderstorm, there is usually only one main updraft, which is warm, damp air and drawn from places near the ground. Storms need warm and damp air as fuel, so they typically draw that air in from surrounding environment. Storms can draw in the air that fit their need from all directions—even from the direction in which the storm is traveling.

    As the warm, damp air is pulled into a storm system, it leaves a low－pressure vacuum(真空) coming after. The rising air meets the cold dry air that has already existed in the storm clouds, thus the temperature of the warm, damp air drops, and the water vapour (水蒸汽) in it changes into tiny drops that are a precondition of rain. These drops accumulate and build on larger particles like dust, until they grow large enough to form raindrops.

    This warm, damp air keeps moving upwards, but it becomes cooler and drier during its trip through cloud. When it reaches the top of the cloud, the air gets spit out(被挤出) at the top. This air is sent rolling out over the big thunderclouds. From there, the air goes down. Warm and dry air is relatively stable, and once it covers a region, that air, in turn, causes the calm before a storm.

    Most thunderstorms, though, don't start with calm. That's because most are actually groups of storms with complex wind patterns. There's so much air moving up and down storm groups that the calm before the storm never happens. Instead, before the storm, it might be really windy!

    Do you need useful and interesting books? Here we've got plenty for you.

Successful Fishermen

    Fishing is a healthy hobby. You can enjoy fresh air when you go fishing in the countryside. This book will teach you how to choose fishing places and how to make good fishing rods(竿) easily. Many kinds of fishing skills are shown in the book. Read it and you will become a more successful fisherman.

    Best Learners

    This book can give you the answers to the questions most often asked by parents, teachers and students themselves. Read this book and learn:

    What the three difficulties in study are and how to deal with them.

    What to do if you are not interested in a subject you are studying.

    Twenty­six simple exercises to help you study easily and fast.

    You will get more from this book. For younger students, you can buy Learn in Study for Beginners. It is easier to understand.

    How to Keep Pets

    A pet can be our best friend. Do you have pets in your house? Are they in good shape? This book not only offers you many colorful pictures of lovely pets, but also provides you with the knowledge about:

    How to choose right pets for yourself.

    How to build houses or nests(窝) for your pets.

    How to feed the pets and how to keep them clean.

    Buy this book and you will learn more.

    We have many other books on sale. For more information enter www. knowbetter com. If you buy two or more books at a time, you'll get 10% off.

    Sagrada Familia (2, 056, 448 visits /year)

    Opening hours: 09: 00-18: 00 (October-March)    09: 00-20: 00 (April-September).

    Admission: $11, or $10 with the Barcelona Card.

    Disabled access: Yes.

    The temple has been under construction since 1882 and they've still got another 30 to 80 years to go before it will be finished. The project's vast scale (规模) and its special design have made it one of Barcelona's top tourist attractions for many years.

    La Pedrera (1, 133, 220 visits /year)

    Opening hours: 09: 00-18: 30 (November-February)    09: 00-20: 00 (March-October)

    Admission: $9.50. Save 20% with the Barcelona Card.

    Disabled access: No.

    This building used to be called Casa Mila, but nowadays it's more commonly known as La Pedrera. It was made of bricks and had colorful tiles (瓷砖).

    Barcelona FC Museum (1, 032, 763 visits /year)

    Opening hours: 6th April-4th October: (Monday to Saturday) 10: 00-20: 00; the rest of the year: 10: 00 to 18: 30.

    Admission: $8.50 for entry to museum and an extra $17 for a guided tour.

    Disabled access: Yes.

    It is now generally considered as the best football museum in the world. You can see so many trophies (奖杯), pictures and statues of great football players. I'm not a football fan but I still enjoyed walking round this museum.

    Miró Museum (518, 869 visits /year)

    Opening hours: Check website for details as they vary depending on the time of the year.

    Admission: $8. Save 20% with the Barcelona Card.

    Disabled access: Yes.

    This museum has a wide range of Miró's works dating back as far as 1914. This artwork collection includes not only his paintings but also a good selection of sculptures.

Gorgeous Mother's Day Gift

If you're stuck for a Mother's Day gift, why not try something that tugs at the heartstrings? A company that specialises in turning life stories into long-lasting books has developed a simple way to show your mother or grandmother how much they mean to you.

The company has created a full-colour book that captures all your family memories. And it's a gift that can be enjoyed over and over again by future generations. The company sends you a set of questions by email, and these help you make a personalised book that's unique to your parent or grandparent.

This hardbound（精装的） book is a bargain compared to a private autobiography, which can cost thousands of pounds and take ages to finish.

The company was started by two siblings. After their dad died young and they saw their grandma struggle with Alzheimer's, they wanted to find a way to save life stories before it was too late. When you buy a photo book, the company will give some money to the Alzheimer's Society charity. They help you make the book and keep your stories safe until it's printed.

The photo book costs£149, but you can pay £50 more to get an extra copy for your family and friends. If the person who gets the book doesn't like it, they can get their money back in 30 days.

As a cheaper alternative, you could get an £11.99 scrapbook from the Internet and put your own pictures in it to save money. The company also sells different kinds of photo books, like the Mini Hardback Photo Book which is now only £20.80, down from £26.