【推荐1】In nature, smaller animals often “take a ride” on larger ones to save energy on long-distance movements. In paper published in the journal Current Biology, researchers show how fine Caenorhabditis worms can use electric fields to “jump” across Petri plates or onto insects, allowing them to go through the air and attach themselves, for example, onto naturally charged bumblebees (大黄蜂).

“Pollinators(传粉昆虫), such as insects and hummingbirds, are known to be electrically charged, and it is believed that pollen (花粉) is attracted by the electric field formed by the pollinator and the plant,” says Takuma Sugi, a co-senior author on the study. “However, it was not completely clear whether electric fields are used for communications between different land animals.”

The researchers first began studying this project when they noticed that the worms they developed often ended up on the lids of Petri dishes. When the team attached a camera to observe this behaviour, they found that it was not just because worms were climbing up the walls of the dish. Instead, they were jumping from the floor of the plate to the top.

Next, the researchers rubbed flower pollen on a bumblebee. Once close to these bees, worms stood on their tails, then jumped aboard. Some worms even piled on top of each other and jumped in a single post, moving 80 worms at once across the gap.

“Worms stand on their tail to make it easier for themselves to attach to other passing objects,” Sugi says. “In a post, one worm lifts more worms, and this worm takes off to move across the electric field while carrying all the post worms.

Researchers observed jumping in other worm species closely related to C. elegans, and they noted that mutants (突变体) who are unable to sense electric fields jump less than their normal counterparts. However, more work is needed to determine exactly what genes join in making these jumps and whether other microorganisms like bacteria can use electricity to jump as well.

【推荐2】Much like the popular TikTok challenge where kids resist eating snacks, cuttlefish can do the same! Cuttlefish can delay gratification(满足)—wait for a better meal rather than be tempted by the one at hand—and those that can wait longest also do better in a learning test, scientists have discovered.

This fascinating report marks the first time a link between self-control and intelligence has been found in an animal other than humans and chimpanzees. It is published this week in Proceedings of the Royal Society B. The research was conducted by lead author Alexandra Schnell of University of Cambridge, at the Marine Biological Laboratory(MBL), Woods Hole.

“We used a slightly-changed version of the Stanford marshmallow(棉花糖) test in the 1970s, where children were given a choice of taking an immediate reward(1 marshmallow) or waiting to earn a delayed but better reward(2 marshmallows),” Schnell says. “Cuttlefish in the present study were all able to wait for the better reward and tolerated delays for up to 50—130 seconds, which is even comparable to what we see in large-brained vertebrates(脊椎动物) such as chimpanzees(黑猩猩), crows, and parrots.” Cuttlefish that could wait longer for a meal also showed better cognitive(认知的) performance in a learning task. In that experiment, cuttlefish were trained to associate a visual cue with a food reward. Then, the situation was the other way round, so the reward became associated with a different cue. “The cuttlefish that were quickest at learning both of those associations were better at keeping self-control.” Schnell says.

Why cuttlefish have evolved this capacity for self-control is a bit mysterious. Delayed gratification in humans is thought to strengthen social bonds between individuals—such as waiting to eat so a partner can eat first—which benefits the species as a whole. But whether it may also be a function of most animals still remains to be further explored.

【推荐3】It’s official. Britain is to be reforested. A Tree Action Plan will deliver half a billion more trees by 2050.

Britain is one of the most treeless countries in Europe, trees covering about 10 percent of its land — around a quarter of the European average. The bare state of the British landscape is nothing new. It is a false idea that a squirrel could ever have crossed the country by jumping from tree to tree.

Certainly, at around three billion of trees, we have twice as many as a century ago. However, about a third of them is in monoculture (单一种植) plantations of fast-growing non-native species like Sitka spruce, grown to make paper. These plantations lack biodiversity — more tree farms than forests.

But it would be great to have more trees: for the climate, for biodiversity and for ourselves.

Can we do it? Past efforts to regreen Britain have not gone too well. In the 1990s, the government had a plan for a national forest in the Midlands. It promised 30 million trees. Thirty years on, they have managed nine million. Older readers may remember the project “Plant a Tree” in 1973. I remember planting one in Cambridge. But the trees were taken little care of and nobody tracked them. Mine died, as no doubt did many others.

The trick is not to repeat past mistakes by growing single-species forests. We need ecological (生态的) diversity. Another rule should be to plant where there were trees before. But if the rules for planting begin to sound a bit troublesome, maybe there is a better way. Not to plant at all. Often it is better just to create room for trees to regenerate naturally, self-seeding from nearby woodlands. Consider what the author of the best-selling book Wilding did on herd farm. She went away from the fields and stood back, letting the trees self-seed from nearby woodlands with the help of birds that brought in seeds. Two decades on, she had a woodland. My final suggestion is that instead of throwing all our money into headline-friendly but short-sighted planting projects in the countryside, let’s have more trees where most of us live, too.

【推荐2】Hyde Park, one of London’s best parks, spreads itself over about 350 acres of neat gardens, vast wilderness overgrown with grass and splendid trees. As well as being a fantastic green space in the middle of the city, it’s home to a handful of appealing sights, and hosts live concerts and events throughout the year.

Hyde Park was created for hunting by Henry VII, who obtained it from the church in 1536. It was enclosed as a deer park and remained a private royal(皇家)hunting ground until James I permitted limited access to the upper-class people. In 1637, Charles I opened the park to the general public.

The eastern half of the park is covered with vast lawns(草地), which become superb picnic areas on sunny days. The western half remains in a wild state, with plenty of trees and areas of wild grass. If you’re after somewhere more colorful, head to the Rose Garden, a beautifully landscaped area with flowers year-round. You won’t want to miss the Diana, Princess of Wales Memorial Fountain either.

In the northeast part of the park, you’ll find Speakers’ Corner, where speakers step up to give speeches, discussions and debates on various topics. This is an interesting and unusual place to visit, where you can see people gather to listen, applaud or laugh at different speakers. Speakers’ Corner became famous during the Second World War. Nowadays, it is possible to speak public-ally on any topic, as long as the police consider it lawful.

Since 2007, Hyde Park has played host to the annual Winter Wonderland event, which features numerous Christmas-themed markets, along with various rides and attractions, bars and restaurants. It has expanded to include the largest ice rink(溜冰场)in London and live entertainment, and has become one of the largest Christmas events in Europe, having attracted millions of visitors.

【推荐3】A woman’s husband divorced her because she spent too much time on the Internet. But she continued to surf the World Wide Web. She did this so often that she forgot to take her children to the doctor or get the kids enough food. Her husband asked the court for the children.

But he needed someone to support her illness. “I had to write a letter to the judge,” said Dr. Jonathan Kandell. “The judge did not believe there was such a thing as Internet addiction.”

Is there? Some psychologists say that Internet addiction is real, just like gambling or drug abuse.

At the University of Maryland, a doctor started an Internet addiction support group after he watched a few addicted students nearly failed school.

How can you tell if you have an abnormal pattern of Internet use? Do you need to spend increased amounts of time on the Internet to achieve satisfaction? And when you’re not online, do you have fantasies or dreams about the Internet?

Tyler Johnson, 17, a high school senior in Abbotsford, British Columbia, spends more than six hours a day online and more than an hour reading his email.

Tyler dropped out of school sports, and now, every day after school until 3 or 4 o’clock in the morning, he plays games on the Internet.

Dr. Kandell guesses that many addicts don’t get help because they don’t know they have a problem. “I think we’re about a year away from having people recognize it’s really a problem,” he said. “It’s out there. There’s no question.”