Jealousy is such a powerful emotion that at least one study has characterized it as the third leading cause of non-accidental homicide(杀人) in all cultures. In a recently published study, researchers experimented with dogs to see whether they, like humans, have the nature of jealousy.

In an experiment, the authors took 36 dogs—along with their owners—and observed the dogs' behavior as their masters interacted with three non-living objects. One object was a children's book, which they read aloud; another object was a plastic pumpkin lantern; and the third was a mechanical stuffed dog that gave out a bark when the owner pressed a button.

    Former studies concluded that babies were probably capable of jealousy. In the experiment, their mothers showed attention to a life-like doll instead of their child, and other objects. The babies were reportedly more likely to respond with “negative” behavior if their mother turned to pay her attention to the doll.

    In the dog experiment, authors instructed the dog owners to push the bark button on the stuffed dog's head, and then speak to it sweetly, while ignoring their own dog. After that, they showed attention to the pumpkin lantern, and read the children's book, while also ignoring their dog.

    It is interesting to see the dogs were far more likely to act aggressively when their owners spoke to the stuffed dog than when they paid attention to the other objects. One-fourth of the dogs snapped at the stuffed dog, while only one dog snapped at the lantern or the book. The dogs were also more likely to push or touch their owners as they interacted with the mechanical dogs, and tried to get in between the owner and the stuffed dog more frequently than the other objects.

    “One possibility is that jealousy developed in species of many young relying on the parents, the young compete for parental resources such as food, attention, care, and affection,” the authors wrote.

    Some people think that success is only for those with talent or those who grow up in the right family, and others believe that success mostly comes down to luck. I'm not going to say luck, talent, and circumstances don't come into play because they do. Some people are born into the right family while others are born with great intelligence, and that's just the reality of how life is.

    However, to succeed in life, one first needs to set a goal and then gradually make it more practical. And, in addition to that, in order to get really good at something, one needs to spend at least 10,000 hours studying and practicing. To become great at certain things, it'll require even more time, time that most people won't put in.

    This is a big reason why many successful people advise you to do something you love. If you don't enjoy what you do, it is going to feel like unbearable pain and will likely make you quit well before you ever become good at it.

    When you see people exhibiting some great skills or having achieved great success, you know that they have put in a huge part of their life to get there at a huge cost. It's sometimes easy to think they got lucky or they were born with some rare talent, but thinking that way does you no good, and there's a huge chance that you're wrong anyway.

    Whatever you do, if you want to become great at it, you need to work day in and day out, almost to the point of addiction, and over a long period of time. If you're not willing to put in the time and work, don't expect to receive any rewards. Consistent, hard work won't guarantee you the level of success you may want, but it will guarantee that you will become really good at whatever it is you put all that work into.

    We bet that on cold winter days, many of you love to stay in your warm home and, every now and then, come out into the kitchen for a snack. Unfortunately, plenty of small insects like to do the same thing! Winter is the time when small insects enter your house without an invitation. The season can be difficult for such creatures. In winter the air is cold, the ground is hard and many trees have no leaves. So small insects do what they have to do to survive.

    Monarch butterflies head south to warmer climates. Ants crowd in deep underground colonies and eat food they have been storing all year. Many insects go into a deep sleep called diapauses. There're different kinds of diapauses, but all are similar to hibernation, a time when bigger animals become inactive in the cold. Insects go into an inactive period, too, but it often isn't when the temperature drops.

    They rely on more dependable signals in the environment. For example, many insects can tell how much sunlight there's each day. They use that to tell themselves when to shut down. Insects are cold-blooded, meaning that their inside temperature is the same as the outside. They can't move much when it gets below 40 degrees Fahrenheit. So they search for any warm place.

    They're looking for protection. These guys have been doing this for 300 million years, so they don't really know they're coming into your house. The home is a recent event in terms of their evolutionary (进化的) behavior. They enter through tiny cracks or come in unnoticed on your clothes or shoes. Remember that they may be entering your homes for warmth and food, but they don't care about humans.

The best books of the year

    Vacation in the U. S. usually means slower days, and no school teachers know, however, that vacation means students will likely fall behind, and forget things they learned during the year. Simon Vanderpool, a special education teacher in Lexington, Kentucky, decided to do something about it.

    He started a program called Books and Barbers. Children go to the barber, choose a book and read out loud while the barber cuts their hair. The child gets a sticker and can take the book home. And there is an added bonus: money. The kids get paid to read.

    Vanderpool says barber shops are places where kids can feel comfortable. "Once a student feels comfortable, that's whenever the brain opens up, and that they are able to start focusing on nothing but learning." Amir Shalash owns a barber shop. But he is doing more than cutting children's hair. He is listening to them read, and helping them with their reading.

    Most of the children getting haircuts at barber shops are boys. Vanderpool's idea was to do more than just help them with reading and money. The teacher wants to help kids who are growing up in a home without a father liike he did. Also, I created the program in order to provide a positive mentor(指导者）for the kids that go into the barber shop, and are able to have someone that they can rely on and they can trust in, and just build a bond between the two of them." Shalash says he and his fellow barbers like being mentors.

    "The biggest thing is that we try to influence as many kids as we can, and that was my whole intention of it."

A study of 500,000 songs released in the UK between 1985 and 2015 showed that pop music had decreased in happiness and increased in sadness.

In a report published in the journal Royal Society Open Science, researchers at the University of California examined hundreds of thousands of songs and classified them by their mood. "‘Happiness' is going down, 'sadness' is going up, and at the same time, the songs are becoming more 'danceable' and more 'party-like'," co-author Natalia L. Komarova told The Associated Press.

The study found songs in 2014 like Stay With Me by Sam Smith, Whispers by Passenger and Unmissable by Gorgon City have a "low happiness" trend. However, tracks from 1984 like Glory Days by Bruce Springsteen, "Would I Lie To You?" by Eurythmics and "Freedom" by Wham had a "high happiness" trend. "The public seems to prefer happier songs, even though more and more unhappy songs are being released each year," the researchers wrote.

Apart from the emotional trends, researchers discovered that dances and pop were the most successful styles of music and that there was a "clear downward" trend, with the popularity of rock beginning in the early 2000s. "So it looks like, while the overall mood is becoming less happy, people seem to want to forget it all and dance," Komarova wrote in an email.

It was also found that the "maleness" of songs—the frequency of male singers in popular music-had decreased during the last 30 years. "Successful songs are characterised by a larger percentage of female artists compared to all songs," they wrote.

This discovery appears at a time when the conversation around sex equality in the music industry is at its height, with more male artists and songwriters.