【推荐2】Scientists have come up with a new way of identifying animals in an area by testing DNA taken in from the air. The researchers believe their new method could help scientists keep track of animals that are hard to spot, including endangered animals.

Two teams of scientists—one in Denmark and one in the United Kingdom (UK)—came up with the same question at about the same time: Could they identify the animals in an area from DNA that was simply floating in the air?

Testing for eDNA isn’t a new idea, but most of the time, scientists look for eDNA in water. DNA in the air is usually so small that it would take a microscope to see it. The scientists didn’t have high hopes for their experiment. Neither team knew that the other group was working on a similar experiment. One collected samples from different locations at Denmark’s Copenhagen Zoo, and the other at Hamerton Zoo Park in the UK. The scientists used slightly different methods to collect their samples. But basically, both teams collected extremely tiny bits of DNA onto very high quality filters.

In the laboratory, they got the DNA from the filters and made copies of it to study. By comparing their samples with examples of DNA from different animals, the scientists were able to identify many different animals at the zoos.

Each team only discovered about the other experiment after they had written a paper about their own results. Instead of competing, the two decided to combine their results and publish a paper together.

Both teams are excited about the ways this new method could be used in the wild. Scientists have been looking for better ways to track endangered animals without interfering with them. If researchers know where animals live, they can do a better job of protecting them. “The next step is to figure out how to take this method into nature,” says Dr. Bohmann , one of the scientists on the Copenhagen team.

【推荐1】Recently, one of my best friends, whom I’ve shared just about everything with since the first day of kindergarten, spent the weekend with me. Since I moved to a new town several years ago, we’ve both always looked forward to the few times a year when we can see each other.

Over the weekend, we spent hours and hours, staying up late into the night, talking about the people she was hanging around with. She started telling me stories about her new boyfriend, about how he experimented with drugs and was into other self-destructive behavior. I was blown away! She told me how she had been lying to her parents about where she was going and even stealing out to see this guy because they didn’t want her around him. No matter how hard I tried to tell her that she deserved better, she didn’t believe me. Her self-respect seemed to have disappeared.

I tried to convince her that she was ruining her future and heading for big trouble. I felt like I was getting nowhere. I just couldn’t believe that she really thought it was acceptable to hang with a bunch of losers, especially her boyfriend.

By the time she left, I was really worried about her and exhausted by the experience. It had been so frustrating, I had come close to telling her several times during the weekend that maybe we had just grown too far apart to continue our friendship，but I didn’t. I put the power of friendship to the ultimate test. We’d been friends for far too long. I had to hope that she valued me enough to know that I was trying to save her from hurting herself. I wanted to believe that our friendship could conquer anything.

A few days later, she called to say that she had thought long and hard about our conversation, and then she told me that she had broken up with her boyfriend. I just listened on the other end of the phone with tears of joy running down my face. It was one of the truly rewarding moments in my life. Never had I been so proud of a friend.

【推荐2】I recently attended a wedding in a rural area in north Italy, and guests were provided with a car and driver for the 90-minute journey into the hills. That was exciting: A private car! I could pretend I was rich! Since I’m not, though, I had no idea how much this trip actually cost. As a result, after our driver picked us back up at midnight, I secretly worried all the way home about tipping him.

I fished around nervously in my purse and realized that all I had was a $100 note, which I was keeping for an emergency. I had nothing smaller. And I had nothing else to offer but two chocolates from the wedding. So, I could tip the driver that $100 note or two chocolates. In the end, I chose the money.

The whole matter of tipping has long been a source of awkward interactions — and, for some travellers, mild anxiety — throughout the world. Tipping customs vary wildly from country to country. A friend in Rome tells me that Italians get hurt by big tips. “Leaving a big tip is considered impolite,” she adds, “I’ve had Italian friends make me take money back.”

It reminded me of my 100-dollar tip. What if I had annoyed the driver? So I decided to call the car company and ask them to pass on a message to the driver apologizing for the improper tip and explaining the situation.

To my surprise, the car company responded that the driver had actually called to express his gratitude for the unexpected big tip. He had apparently been having a tough week and the money had come at just the right time.

I was astonished. All my worry had been for nothing. What started out as a source of anxiety ended up being a heartwarming experience. I learned that sometimes it’s better to go with your feelings and be generous, even if it means taking a risk.