【推荐1】Scientists have recently discovered that Andean condors (秀鹫)— some of the world’s largest birds——barely flap their wings at all while flying. Instead, they use rising air currents to remain in the air for hours.

The Andean condor is the world’s largest soaring bird. They can weigh up to 15 kilograms. Their wings, when spread out, measure up to three meters. Their main food source is the meat of large animals which have died. Soaring high in the sky allows condors to easily spot possible meals on the ground.

Scientists worked together to study the flight patterns of these huge birds and how much effort the birds use when flying. To study the birds while they were in the sky, the researchers attached special devices which could record every beat of their wings.

The scientists learned that most of the condors’ flapping— over 75%— came when the birds were taking off. Once in the sky, the birds flew for very long periods of time without flapping at all. In fact, they only flapped their wings for 1% of the time they were in the air. One bird flew for over five hours without flapping, covering nearly 117miles.

Soaring without flapping is important because birds burn energy every time they flap their wings.

The birds’ soaring isn’t magic. They use the fact that hot air rises to keep themselves up. As hot air rises, it often creates “thermals”— currents of warm air moving upward. The condors soar by making use of these thermals. The tricky part is finding thermals and moving between them.

When birds are forced to land and take off again often, it costs them a lot of energy. The researchers learned that to avoid having to land, the condors did most of their non-take-off flapping when they were closer to the ground and looking for a new thermal.

The scientists reported that even though all of the condors they studied were young, they knew well how to take advantage of the air currents.

【推荐2】A new study reveals that pigeons (鸽子) can tackle some problems just like artificial intelligence, enabling them to solve difficult tasks that might challenge humans. Previous research has theorized that pigeons employ a problem-solving strategy, involving a trial-and- error approach, which is similar to the approach used in AI models but differs from humans’ reliance on selective attention and rule use. To examine it, Brandon Turner, a psychology professor at the Ohio State University, and his colleagues conducted the new study.

In the study, the pigeons were presented with various visual images, including lines of different widths and angles, and different types of rings. The pigeons had to peck (啄) a button on the right or left to indicate the category to which the image belonged. If they got it correct, they received food; if they were wrong, they received nothing. Results showed that, through trial and error, the pigeons improved their accuracy in categorization tasks, increasing their correct choices from about 55% to 95%.

Researchers believed pigeons used associative learning, which is linking two phenomena with each other. For example, it is easy to understand the link. between “water” and “wet”. “Associative learning is frequently assumed to be far too primitive to. explain complex visual categorization like what we saw the pigeons do,” Turner said. But that’s exactly what the researchers found.

The researchers’ AI model tackled the same tasks using just the two simple mechanisms that pigeons were assumed to use: associative learning and error correction. And, like the pigeons, the AI model learned to make the right predictions to significantly increase the number of correct answers. For humans, the challenge when given tasks like those given to pigeons is that they would try to come up with rules that could make the task easier. But in this case, there were no rules, which upsets humans.

What’s interesting, though, is that pigeons use this method of learning that is very similar to AI designed by humans, Turner said. “We celebrate how smart we are that we designed artificial intelligence: at the same time, we regard pigeons as not clever animals,” he said.

【推荐3】Like members of a street gang, male dolphins call on their buddies when it comes time to attack—or, in their case, to catch and defend females. A new study shows that they do this by learning the whistles, of their closest allies—sometimes more than a dozen animals—and remembering who consistently cooperated with them in the past. The findings indicate dolphins have a concept of team membership—previously seen only in humans—and may help reveal how they keep such complicated and tight-connected societies.

Male dolphins typically cooperate as a pair, which researchers call a “first-order alliance.” These small groups work together to find and catch a female. Males also cooperate in second-order alliances consisting of as many as 14 dolphins which defend against opponent(对手) groups attempting to steal the female. Some second-order alliances join together in even larger third-order alliances, providing males in these groups with even better chances of having allies nearby if enemies should attack.

But how do the males keep track of everyone in these complex groups?

Scientists have argued that their whistles are key. Every dolphin learns a unique signature whistle from its mother, which it keeps for life; dolphins recognize and remember each other’s whistles, similar to how we recognize each other’s names.

To further investigate how the male dolphins use their whistles, King and her colleagues turned to a population of Indo-Pacific bottlenose dolphins. The team has tracked the animals with underwater microphones since 2016, enabling them to identify which dolphin produces which whistle.

The researchers expected that males hearing the whistle of their first-order alliance partners would respond most strongly. But when they reviewed the videos, they found the strongest responses came from males in the dolphins’ second-order alliances—animals who had a firm cooperative history of fighting off attackers with them.

“It was so striking,” says King, leading author of the study. “In 90% of experiments, dolphins who heard whistles of second-order alliance members turned immediately and directly toward the speaker.” The findings, she says, suggest dolphins—like humans—have a “social concept of team membership, based on an individual’s previous cooperative investment, rather than how good friends they are.”

【推荐2】There’s a long line of research showing that when we make contact with people who’re socially different from us, we tend to feel less prejudice towards them. According to the contact theory, contact seems to work best for reducing prejudice when the contact is generally positive. But what happens when the conditions for interpersonal contact may not be ideal? For example, what if you feel threatened in some way by a group of people you see as “the other”?

Researchers from Ghent University in Belgium analyzed the results of 34 studies surveying nearly 64,000 people from 19 countries to see how intergroup contact affected their viewpoints about “outgroups” under conflict situations. For example, people were asked to report on how they viewed other groups. The researchers also had data from the surveys that measured attitudes towards outgroup members, such as how positive people felt towards them and how much they could trust them.

After analyzing the data, the researchers found strong feelings of threat were associated with more negative views of outgroup members. But having contact with outgroup members still reduced prejudice just as much under those unfavorable conditions. To Jasper Van Assche, the lead author of the paper, this suggests contact theory holds even under conflict situations.

Van Assche says that contact is so powerful probably because just being around people from an outgroup affects how we think and feel about them. As we become accustomed to even the me re presence of people from other groups, that can reduce our anxiety, especially if the encounters are positive—and that can lead to warmer feelings. Also, contact can enhance our knowledge about others’ customs and practices, so that they don’t seem so foreign or “other” to us.

Van Assche hopes his research can lead people to see the benefits of integrating the spaces where they live. This could be done through top-down methods, such as the government requiring school integration, but also from the bottom up. For example, suggests Van Assche, communities could create low-cost, low-key events that bring people together, helping to promote tolerance.

【推荐3】The British are the most voracious(如饥似渴的) newspaper readers in the world.

They read newspapers at breakfast; they walk to the bus reading a newspaper; they read a newspaper on bus, as they go to work; and on the way back home, after work, they are engaged in reading an evening newspaper.

There are many “morning papers”, both national and provincial. The most famous is The Times. Different from what many foreigners believe, this is not a government newspaper. The various newspapers usually have their own views of the Communist Morning Star. The Labor Party and the Trades Union Congress no longer have a daily newspaper to represent them.

Bold headlines and a variety of photographs are features of the British press. Some newspapers, such as the sober Daily Telegraph and The Times, use photographs sparingly(节省). The more “popular” newspapers, using the small or “tabloid”(小报) format, such as the Daily Express, the Mail, the Daily Mirror and the Sun, use pictures extensively and also run strip cartoons and humorous drawings, some of which present striking pictorial comment on politics.

Besides offering features common to newspapers all over the world, British newspapers specialize in pages devoted to criticism of the arts and a woman's page. One feature found in many foreign newspapers is missing in British papers: the serial(连载).

Nearly all papers pay special attention to the reporting of sports and athletics. The evening newspapers are often bought because the buyer wants to know the winner of a race, or to get good tip for a race that is still to be run. There is no censorship(审查) of the press in Britain (except in wartime), though of course all newspapers—like private persons—are responsible for what they publish, and can be sued for libel(为诽谤而被起诉), for publishing articles that go beyond the bounds of decency(正派), or for ignorance of court. (e.g. calling a man a murderer while he is still being tried. Such cases are not often)