【推荐3】These days, Fred’s huge skeleton (骨架) was exhibited in the Indiana State Museum. His tusks (长牙) were recently the subject of a research study tracing the life 13,000 years ago of mastodons, distant relatives of modern elephants.

By analyzing the chemicals in Fred’s tusks, a team of researchers was able to construct a detailed account of his seasonal migration patterns. Josh Miller, a paleoecologist (古生态学家) at the University of Cincinnati, is one of the researchers studying Fred. “He has beautifully preserved bones and tusks, which provides a great opportunity for our research,” Miller said.

Mastodons’ tusks generally grow in distinct layers, similar to the tree rings. As a result, the nutrients that build the layers of their tusks can tell us a lot about what they experienced. The team particularly focused their analysis on the variations in two elements in the layers: strontium (锶) and oxygen. The former is the key to understanding where Fred spent his life, while the latter tells us the season he was in any particular region. Then, with some statistical modeling, Miller and his team gained insight into the daily record of Fred’s behavior over ten thousand years ago.

The result indicated that when Fred was young, he would have grown a lot. But there’s a year when his growth is reduced — that’s when Miller’s analysis starts. “Probably like the modern male elephant, a male mastodon is just really obnoxious when growing up to be a bother and often arouses family members’ anger. At that point, the mom and aunts will essentially kick him out of the family”, Miller predicted.

After Fred set off to attend to himself, his tusks reflected where he traveled around. Based on analysis, every summer, Fred would return to mate in Northeastern Indiana, because around this time, his tusks started to show signs of injuries. When competing for mates, mastodons got into huge battles with their own natural weapons, sharp tusks. And that was exactly what brought the story of Fred to an untimely end.

【推荐1】A new study published Monday in an American Heart Association journal Hypertension, examined 360,000 participants who provided blood, urine and saliva (唾液) samples, as well as detailed information about their lifestyles. Researchers found that adults who napped often were more likely to develop high blood pressure and have a stroke. But that doesn’t mean the napping causes these health issues — instead, napping may be due to unhealthy behaviors. The researchers found that a high percentage of frequent nappers reported cigarette smoking, daily drinking, insomnia (失眠症) and other factors that could contribute to health-related issues.

Dr. Margaret Blattner, clinical instructor, from the department of neurology at Beth Israel Deaconess Medical Center, tells PEOPLE that frequent or long daytime naps can disturb healthy nighttime sleep. Napping during the day may make it harder to fall asleep at night or cause nighttime sleep to become fragmented and that missing out on night time sleep can cause severe daytime sleepiness.

“Often, naps continuing long are less restorative than more brief daytime naps; people often wake up unrefreshed after a long nap,” she adds. “Additionally, long day time naps take away time from other healthy things that people enjoy during the day: spending time with family, enjoying hobbies, and exercise.”

When napping during the day becomes unpredictable, uncontrollable, or prevents an individual from accomplishing what they need or want to do, it could indicate a possible sleep disorder.

But Blattner assures that taking naps can also be beneficial. ”Napping is not always a cause for concern. Taking a nap can be refreshing and enjoyable,” she says. “The key is, are you missing out on things that you enjoy because you are too sleepy to stay awake — that can indicate a problem -or does the nap help you get more out of your day?”

“Taking a brief nap can feel restorative, reduce stress, and improve focus. Early afternoon is a good time to nap, as this agrees with a physical circle dip in energy,“ Blattner continues.” However, napping too late into the afternoon or evening may impact night time sleep quality and make it harder to fall asleep.”

【推荐3】For generations, the standard way to learn how to ride a bicycle was with training wheels. But in recent years, many parents prefer to train their kids with balance bikes, two-wheelers that enable children to develop the competence needed for bicycling.

Given the benefits of balance bikes, why did it take so long for them to replace training wheels? There are plenty of other examples in which ignored solutions that involve subtraction(减法) turn out to be better alternatives. In some European cities, for example, urban planners have gotten rid of traffic lights and road signs to make streets safer.

Leidy Klotz, an engineer at the University of Virginia, noticed that reformative designs, in which elements are removed from an existing model, were uncommon. So he reached out to Adams, a social psychologist, to try to figure out why this was the case. The two researchers hypothesized(假设) that there might be an explanation: when faced with a problem, people tend to select solutions that involve adding new elements rather than taking existing components away.

Adams, Klotz and their colleagues set out to test if their hypothesis was correct. The researchers first carried out a set of studies. In one, they asked 91 participants to make a pattern symmetrical(对称的) by either adding or removing colored boxes. Only 18 people used subtraction. In another, the team scanned through ideas for improvement submitted to an incoming university president and found that only 11 percent of 651 project plans involved getting rid of an existing regulation, practice or program.

These findings suggest that “additive solutions have sort of a priority”, says Benjamin Converse, a co-author of the study. “Subtractive solutions are not necessarily harder to consider, but they take more effort to find.”

For now the team hopes that these findings will encourage people across various fields to think about subtractive options that might be typically ignored. “The hope is that, just by getting people to think about this more, maybe it will help inspire some other ignored subtractions,” Converse says.

【推荐1】Imagine that you’ve just finished taking a multiple-choice test, and you start to second-guess one of your answers. You have some extra time — should you stick to your first instinct (直觉) or change it? About three quarters of students are convinced that changing their answers will hurt their scores. Experience indicates that many who change answers change to the wrong answer.

Despite the lessons of experience, what does evidence say? In a review of thirty-three studies, three psychologists found that the majority of answer changes were from wrong to right. Teachers have also found that students’ final exams have few eraser marks, but those who do rethink their first answers rather than sticking to them end up improving their scores. This phenomenon is known as the first instinct fallacy (谬误).

We don’t just hesitate to rethink our answers. We hesitate at the very idea of rethinking. Take an experiment where hundreds of college students learned about the first instinct fallacy for example. Researchers taught them about the value of changing their minds and gave them advice on when it makes sense to do so. In their next two tests, they were still unlikely to change their answers.

Part of the problem is cognitive (认知的) laziness. Psychologists point out that we favor the comfort of firmly-held beliefs over the discomfort of doubt. Questioning ourselves makes the world more unpredictable. It requires us to admit that the facts may have changed, and that what was once right may now be wrong.

We’ve all heard about the popular story where a frog would immediately escape if dropped into boiling hot water, but it would stay if the water was gradually heated. However, it isn’t true.

The frog will escape as soon as the water gets uncomfortably warm. It is just once we hear the story and accept it as true, we rarely bother to question it. So, it’s not so much changing your answer that improves your score as considering whether you should change it.

【推荐2】At the age of 50, Nina Schoen expects to have a long life ahead of her, but has thought a lot about death—and why people are so reluctant to talk about it: “It’s going to happen to all of us,” she says, “but it should be a more positive experience than the fear we put into it.”

When she first heard about a new end-of-life process that turns the body into compost (堆肥), “I was really moved by the idea,” says Schoen, who became one of the first to reserve a spot with a Seattle-based company called Recompose, the county’s first funeral home to offer human composting.

Last year Recompose began transforming bodies to soil, more formally known as natural organic reduction. Before that, end-of-life options in the U.S. were limited to burial or cremation (火化), both of which come with environmental costs—U.S. cremations alone dump 1.7 billion pounds of carbon dioxide into the atmosphere every year.

Katrina Spade pioneering the composting movement has spent a decade developing the process in hopes of offering people a greener option for death care. “I wondered, ‘What if we had a choice that helps the planet rather than harms it?’” Spade tells PEOPLE. “To know that the last gesture you’ll make will be gentle and beneficial and it just feels like the right thing to do.”

After she had her own two sons, she began to wonder what she might do with her body after death. A friend who knew her interest in the topic reminded her that farmers sometimes compost the body of cows, and that sparked an idea for her theory: “If you can compost a cow, you can probably compost a human,” she thought, and she set about designing a facility to do just that.

“This is about giving people another choice,” Spade says. “At first, people react with shock—‘You really can do that?’ But so many people today are looking at their impact on the Earth. This is a popular thing because when you die, you can give back to the planet.”

【推荐3】There goes the proverb, “The early bird catches the worm.” It has been proven that early bird really does catch the worm, but he saves it for dinner. The Oxford University researchers believe the strategy allows them to stock up on food while it helps avoid falling the victims to predators (捕食者).

A full belly in the morning would slow them down in the hunt for food and make them easy prey. So they search out food when they are lean and light and then dine in the evening to ensure they have a big enough store of fat to survive the night.

The “early bird” strategy was revealed in an experiment in which over 2,000 birds were fitted with tiny radio tags which activated when they landed on feeders hidden in Wytham Woods, near Oxford. The feeders were moved around over the course of the day and the researchers noted when the birds landed on them.

“Our results show these birds display very different patterns of food discovery in the morning and afternoon; very few new food sources were found during the afternoon, whereas nearly every new food source we put out during the morning was quickly discovered.” This revealed that the birds were much better at finding the feeders new locations in the morning. However, they waited until the evening to feast on the worms.

The researchers said the complex strategy acts as an insurance policy, with birds remaining light yet still able to get enough fat to survive the night. It is particularly important in winter when the risks of predation are high and just one day without food can make the difference between life and death for small birds.