In a paper published in the journey Science Advance, researchers describe how Matabele ants, a species of large ant known for attacking termite colonies (白蚁群落), will, after the battle, pick up injured fellow soldiers and carry them back to the nest where they can recover.

    The paper is the latest in a growing body of research that this form of helping behavior, previously observed in some mammals and birds, may not require complex emotion, and may, therefore, be far more widespread in nature than previously thought.

    “Here we have an example of an individual saving another individual,” says lead researcher Erik Frank who conducted the research. “We can be quite certain that the ants don't know why they are doing what they are doing.”

    It's a behavior that pays off for the colony. Our classic conception of worker ants is that they are essentially abandoned, but Mr. Frank and his colleagues calculated that the practice of rescuing nest mates results in a colony size that is a 28.7 percent larger than it would be had the ants left their fellow soldiers for dead.

    “These injured ants are able to recover from their injuries, ” says Frank. “They are essential for the safety and the betterment of the colony. ”

    When a Matabele ant is injured, as often happens during battles with termites, its body will give off two smelly chemicals that tell other ants to carry it back to the nest. Indeed, the researchers found that using these chemicals to seek help from uninjured ants will effectively activate the rescue behavior, supporting their theory that the ants were acting on pure instinct(本能), not more complex emotions.

    “The more we study rescue behavior in ants and other animals, the more we are going to realize that it's not just limited to the species we've observed so far, ” says Karen Hollis, a professor at Mount Holyoke College, mentioning studies that found that dolphins help other injured dolphins to the surface for air, capuchin monkeys defend each other during intergroup battles, and rats free other rats that are trapped.

    Philadelphia offers a ton of attractions that are suitable for people of every age and here are some family—friendly attractions.

    Spruce Street Harbor Park

    Spruce Street Harbor Park, one of the best urban beaches in America, is an outdoor heaven on the Delaware River waterfront. Visitors can relax in a hammock, play on the playgrounds, and play games like table tennis and giant chess. Don't miss out on the park at night, when colorful LED lights hanging from treetops make the entire area bright.

    Blue Cross River Rink

    Offering ice skating in the winter and roller skating in the summer, Blue Cross River Rink creates a fun, outdoor experience for the whole family. Visitors can play on the nine-hole mini-golf course during the summer, and enjoy eats and drinks from the on-site(现场的)bar and restaurant all year round.

    Sesame Place

    Big Bird, Elmo and the other stars of Sesame Street come out and play at Sesame Place, the only theme park in the nation starring the popular TV show's most lovable characters. A water park, interactive activities, parades, fireworks and shows add to the fun.

    Once Upon a Nation Storytelling Benches

    On summer days, uniformed and professional storytellers at 13 storytelling benches throughout Philadelphia's Historic District entertain visitors with true, free, three-to-five minute tales about the colonial(殖民的)era as part of Once Upon a Nation. Children can pick up a Story Flag at any storytelling bench, and then collect a star from every storyteller on their journeys. Flags with all the stars can get free rides on the Parx Liberty Carousel at Franklin Square.

    Can dogs and cats get along well in the same home? People who are thinking about getting a dog as a friend for their cat are worried that they will fight. A recent research has found that if the cat is taken back home before the dog, and if they are introduced when still young (less than 6 months for cats, a year for dogs), it is highly probable that the two pets will get along swimmingly. In two-thirds of the homes cats and dogs have a good relationship.

    However, it wasn't all sweetness and light. There was a reported coldness between the cat and dog in 25% of the homes, while aggression(侵略，好斗) and fighting were found in 10% of the homes. One reason for this is probably that some of their body languages are just different. For example, when a cat turns its head away it means aggression, while a dog doing the same means submission(顺从).

    In homes with cats and dogs living peacefully, researchers found a surprising behavior. They are learning how to talk each other's language. It is a surprise that cats can learn how to talk "Dog", and dogs can learn how to talk "Cat".

    What's interesting is that both cats and dogs have appeared to become smarter. They can learn to read each other's body languages, suggesting that the two may have more in common than was expected. Once familiar with each other's body language, cats and dogs can play together, and enjoy sleeping together on the sofa.

    The importance of this research on cats and dogs may go beyond pets — to people who don't get along well, including neighbors, colleagues at work, and even countries. If cats and dogs can learn to get along, surely people have a good chance.

    Do you have any foreign friends? Do you know their characteristics(特征)?

    The Germans are very quiet and they always keep calm. They don't like to speak many words. They look very serious. They like different kinds of amusements. The Germans are very hard-working. They like tidiness, especially the women, who always keep their home clean.

    In some ways, the Englishmen look the same as the Germans. They are very quiet and never talk too much with the strangers. They are really polite, so we often hear they say “Thank you.” or “Sorry.” The gentlemen are also the Englishmen.

The French's holidays are very long. They like traveling and usually spend their long time on staying in other countries. The Frenchmen are more outgoing than the Germans. It is very easy to make friends with them.

    Compared to the Frenchmen, the Americans are more outgoing. And they are even opener than all of the Europeans. They don't like to depend on others. So it is very common that the students do part-time jobs in their free time. And in Americans' eyes, success is an important part in their life.

    On a recent afternoon, some 60 years after they graduated from grammar school, Kathleen Rys, 72, and her sister Lorraine O'Kelly, 70, sat down and had a meal with a classmate, Bruce Smit, 71 for the first time.

    In the 1950s, Lorraine and Kathleen Rys' family moved from Chicago to Monee. As new kids at Monee Elementary School, they soon found themselves on the outs with other students.

    "I would be with the other guys and see Kathleen walking down the hallway, her head down, holding her books, walking slowly. And all of us guys would be flat against the wall until she passed. Then we'd burst into laughter. How rude is that? It's just crazy." said Smit, a doctor whose wife, Tammy, organized the meeting.

    The women said none of the teachers cared about it. "We just kept it to ourselves. " Lorraine said.

    Over the years, Tammy Smit said, "Bruce would just start to cry at times. He'd wonder what happened to the sisters, if they landed OK." One day a few weeks ago, Tammy took to the internet and found Mary O'Kelly, Lorraine's daughter, and offered to set up a meeting. The idea of revisiting the pain was not well- received by Kathleen, who had never married, let alone gone on a date. It took some convincing, but Lorraine finally got Kathleen to agree to meet with Bruce.

    Bruce broke into tears. "I'm so ashamed, so embarrassed," he said. "But I'm so happy you're still here and that I can finally apologize. " He said he hopes his apology will encourage others to seek forgiveness for the pain they make on others. Lorraine said, "This is a beautiful thing. It's just wonderful that a person from 60 years ago can ask for forgiveness. It's like a miracle to us. It's a healing to us."

I didn't go to Santiago, Chile to look for friendship. In fact, Chile was not even on my wish list.

A mid-life crisis woman, I got a chance to study abroad. I only wanted to learn about global business, taste South American cuisine, and check "study abroad" off my wish list.

On the fifth day, I joined a group for a neighborhood work project aided by the anti-poverty (扶贫) organization. Our tasks were to build a water tower and paint the community center. Upon arrival, I couldn't believe my eyes. It was like a scene out of a horrible film. That moment redefined poverty for me because I had never seen such terrible living conditions. As advised, I showed no signs of the motional battle going on inside me.

Just as I was about to start work on painting, a request came through for a few volunteers to help Nadia, a local resident who volunteered to cook for us. I raised my hand to help because I wanted spend time with the people of the neighborhood despite my shortage of Spanish speaking skills.

Nadia had a sincere smile but not overly friendly. Even without speaking each other's language we started to learn about one another. We chatted about our children, our upbringing, shared picture of our family, struggled to instruct each other to communicate in the other's language, and laugh many times.

After we fed everybody and the dishes were washed, my day was over. But I found myself hesitant to leave. It was as if I had known her my entire life. I had not predicted the unselfishness heart I would encounter, and it was moving.

As we were waiting for the car to pick us up, Nadia showed me her plants that are well-maintains. I could see that despite the hard conditions she was passionate about life. She made me long to be stronger person. She showed me that poverty was external, but happiness was internal. I was seeking to give 100 percent for a well-intentioned cause, but I left receiving 200 percent from her.