Spring is in the air. Birds are singing and beginning to build their nests. It happens every year like clockwork. But by comparing recent observations with century-old eggs preserved in museum collections, scientists involved in the study were able to determine that about a third of the bird species are nesting and laying eggs nearly a month earlier than they did a hundred years ago. And as far as the researchers can tell climate change is responsible.

“Egg collections are such a fascinating to for us to learn about bird ecology over time,” says John Bates, director of the Field Museum. The eggs, with the contents removed, are stored in small boxes and accompanied by labels, saying what kind of bird they belong to, where they're from, and precisely when they were collected

Fidino, an ecologist at Chicago’s Lincoln Park Zoo, built a model for studying the historical and modern data about the egg collections. He found a surprising result: among the 72 bird species studied, about a third are nesting and laying their first eggs 25. 1 days earlier than they did a century ago.

Given that the climate crisis has dramatically affected so many aspects of biology, the researchers looked to rising temperatures as a potential explanation for the earlier nesting and laying. The changes in temperature are seemingly small but lead to different plants blooming and insects emerging—things that could affect the food available for birds. So birds have to move their egg-laying dates to adapt.

In addition to serving as a warning about climate change, Bates believes the study highlights the importance of museum collections, particularly egg collections. “They’re heavy with data about the past, and they can help us answer important questions about our world today,” he said.

Narcissism (自恋) has been something of a mystery to psychologists. With narcissists things tend to be extreme: the good is really good, and the bad is really bad. Expert Keith Campbell compares communicating with narcissists to eating chocolate cakes: “When I at chocolate cakes, 20 minutes later I’m under my desk wanting to die. When I eat vegetables, in 20 minutes I feel good. But given the choice I always eat the cake.”

Some narcissists have great confidence in themselves, and also have the emotional intelligence — the ability to read people and to act accordingly — to develop lasting bonds. Having both, such a person could be a presidential candidate. Other people lack attraction, self-confidence and the skill necessary to make friends. These individuals may have no narcissism. But they lack emotional intelligence as well.

Psychologists from the UK and the US conducted a three-month experiment to analyze the attraction of different groups to their friends. Worst off at the end of three months were students who scored low in narcissism and also low in emotional intelligence. Those who scored high on narcissism and low on emotional intelligence had a large initial following, even if their poor social skills slowed the coming in of new friends over three months. During the three months, the popularity of these narcissists matches that of individuals with low narcissism but high emotional intelligence. This somewhat surprised psychologists. Starting from nothing, the emotionally intelligent earn their friends by doing the hard emotional work of friendship, and invest deeply to sustain those friends. Their following grows when friends of friends join their admiration society.

Psychologists conclude that making and keeping friends is a better strategy for long-term popularity. But whether we attract our friends with self-confidence or win their loyalty (忠诚) with caring and sharing, we will get the friends and followings we deserve.

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（水蒸气）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,让 might be really windy!