1 . Helen Thayer, one of the greatest explorers of the 20th century, loves challenges. She says, “I like to see what’s on the other side of the hill.” She has gone almost everywhere to do that.

In 1988, at the age of 50, she became the first woman to travel alone to the North Pole. She pulled her own sled piled with 160 pounds of supplies, and during her trip no one brought her fresh supplies. Accompanied only by her dog Charlie, she survived cold weather and meetings with polar bears. In fact, Charlie saved her life when one of them attacked her. Near the end of her trip, a forceful wind blew away the majority of her supplies. The last week of the trip, she survived on a handful of nuts and a little water each day.

Helen goes to challenging places not only for adventure, but also for education. Before her Arctic journey, she started a website called Adventure Classroom. On the site, she shares her adventures in order to motivate (激发) students. She explains, “Although kids often see the world in a negative way, without hope for their future, we work to inspire them to set goals, plan for success and never give up.”

Helen grew up in New Zealand. Her parents were athletes and mountain climbers. Following her parents’ example, she climbed her first mountain at 9. Later, she climbed the highest mountains in North and South America, the former USSR and New Zealand.

In 1996, she took on another challenge — the Sahara Desert. She and her husband, Bill, walked 2,400 miles across it! In 2001, she and Bill traveled on foot from west to east through the Gobi Desert in Mongolia. They hope to travel to Sichuan and Tibet in China to study pandas this year.

Helen plans to continue taking trips. She’ll use her explorations, writing, photography and environmental work to create programs for her Adventure Classroom website. She wants to inspire her students never to stop facing challenges!

2 . “I like pigs,” Winston Churchill supposedly once said. “Dogs look up to us. Cats look down on us. Pigs treat us as equals.” Whether Churchill’s contemporary George Orwell also liked pigs is less clear. But he, too, surely saw something in them that was lacking in many domestic (驯养的) animals, for it was they who ended up running the show in his novel, Animal Farm. Pigs, then, are intelligent social creatures.

And, like all animals, they sometimes fight. Some pigs tend to be attackers; others tend to be victims. Who is what depends largely on weight. Among pigs, pounds mean power. The attacker might bite, kick or push the victim. Most conflicts end in seconds, but some last a minute or two.

In most animal species fights would be like that. However, many of the conflicts among pigs Dr Norscia, a biologist, observed had interested parties beyond the fighters. He therefore wanted to understand the role of these bystanders in solving conflicts — and what this says about pigs’ cognitive (认知的) abilities.

Since there was usually not enough time for a bystander pig to become involved in the heat of a conflict, though this did occur, Dr Norscia looked at what happened in the three minutes immediately following a fight. Sometimes, he found, the fighters were reconciled with each other on their own. The more distantly related the fighters were, the more frequently this happened. Dr Norscia guessed that relations between close relatives are more secure to start with, so rebuilding friendly relations rapidly is less necessary for them.

On other occasions, however, a third pig stepped in. Sometimes this bystander interacted with the attacker, which reduced the number of attacks coming after. Sometimes, the bystander interacted with the victim. This appeared to calm the victim down, for it reduced anxiety-related behavior.

Social intelligence need not, though, be entirely selfless. Pigs are more likely to step in after a conflict if they are closely related to either the attacker or the victim. This is probably an example of kin selection (亲属选择), which favors the development of behavior.

5 . Insects (昆虫) are very healthy food. They have almost as much protein (蛋白质) as meat from a pig or cow and are low in fat. Eating insects is also very good for the environment since they need less land and water than larger animals.

Marcel Dicke, who studies insects, explained in a talk how insects also produce more meat from the food they eat. For example, imagine a farmer feeds a cow 10 pounds of food. Those 10 pounds of food produce about 1 pound of meat for people to eat. However, imagine the farmer gives a certain number of insects 10 pounds of food. Those 10 pounds of food produce 9 pounds of meat for people to eat!

Eating more insects can also help people in poor areas. Many people can raise and sell insects, which can provide jobs and food.

But insects will not replace animal meat very quickly. First, people in some countries should have to change how they think about eating insects. Many people in North America and Europe eat a lot of meat like beef and pork. But they do not traditionally eat insects. In fact, for many people in the west, eating insects sounds crazy! They believe insects are dirty and dangerous. Insects make them feel uncomfortable.

Some people are trying to deal with this problem. For example, David George Gordon wrote a book named The Eat－A－Bug Cookbook, which tries to show people   that insects can be delicious. Other insect experts travel around telling people about the benefits of eating insects. But they still have a lot of work to do.

6 . The tomato leafminer moth (飞蛾) originates from Per u and is common throughout South America. However, it has spread through Europe since 2007 and has become one of the largest pests in Mediterranean regions, threatening food supplies. Experts around the world are currently struggling with new ways to battle the moth, but it has developed resistance to pesticides (杀虫剂), leaving farmers helpless to stop the damage. A new study from the University of Portsmouth has shown that the answer may lie in the tropical tent web spider.

Scientists carried out laboratory tests and found that the spiders banded together to form webs that easily caught the flying insects, which they then ate. Dr Lena Grinsted, the lead author of the study, said, “The tropical tent web spiders operate in large groups and can create giant joined-up webs capable of catching insects in the air. This could potentially lead to a reduction of reliance on chemical pesticides, resulting in less pollution in soils, waterways and food chains in the future.”

Crop damage is also caused by the larvae (幼虫), which directly attack the tomato fruit, making the crop ugly and thus unmarketable. Larvae live inside the leaf until they begin the process of turning into a moth, making them difficult to control. However, scientists expect that targeting the adult moth population will reduce the number of eggs being laid. In addition, the spiders build the biggest webs during the summer, which can benefit the tomato planting and growing season in May and June.

The researchers said the study would “open doors for the use of group-living spiders to control agricultural pests” but warned that more work was needed to check the spiders did not change the eco logy of regions. Dr Grinsted added, “Future studies are needed to investigate whether the spiders may negatively impact crop pollination (授粉) by also catching bees and other key pollinators.”