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CaliforniaCondor's Shocking Recovery

      California condors are North America's largest birds, with wing-length of up to 3 meters. In the 1980s, electrical lines and lead poisoning(铅中毒) nearly drove them to dying out. Now, electric shock training and medical treatment are helping to rescue these big birds.

      In the late 1980s, the last few condors were taken from the wild, and there are now more than 150 flying over California and nearby Arizona, Utah and Baja in Mexico.

Electrical lines have been killing them off. “As they go in to rest for the night, they just don't see the power lines,” says Bruce Rideout of San Diego Zoo. Their wings can bridge the gap between lines, resulting in electrocution(电死) if they touch two lines at once.

So scientists have come up with a shocking idea. Tall poles, placed in large training areas, teach the birds to stay clear of electrical lines by giving them a painful but undeadly electric shock. Before the training was introduced, 66% of set-freed condors died of electrocution. This has now dropped to 18%.

Lead poisonous has proved more difficult to deal with. When condors eat dead bodies of other animals containing lead, they absorb large quantities of lead. This affects their nervous systems and ability to produce baby birds, and can lead to kidney(肾) failures and death. So condors with high levels of lead are sent to Los Angeles Zoo, where they are treated with calcium EDTA, a chemical that removes lead from the blood over several days. This work is starting to pay off. The annual death rate for adult condors has dropped from 38% in 2000 to 5.4% in 2011.

Rideout's team thinks that the California condors' average survival time in the wild is now just under eight years. “Although these measures are not effective forever, they are vital for now,” he says. “They are truly good birds that are worth every effort we put into recovering them.”

    Dolphins (海豚) live in a dark underwater world. It's often impossible to see each other or anything else around them, so sound plays an important role in their survival. To communicate with each other, dolphins produce all kinds of sounds.

    Only other dolphins understand what the sounds mean. Scientists haven't uncovered their secret communication, except for one kind of whistle. It might last less than a second, but this whistle is a big deal. Why? Because these whistles are actually names of dolphins — and every dolphin has one. Scientists call these sounds a “signature whistle.” When other dolphins hear the whistle, they know which dolphin is calling.

    Dolphins often hunt by themselves but still need to stay connected to the group. Since they can't always see each other, dolphins use their signature whistles to check in with other dolphins hundreds of yards away. “In coastal areas, dolphins exchange whistles even when they're a third of a mile apart,” says Greg Campbell, who studies animals. That means dolphins shout out to group members that might be nearly five football fields away.

    What's amazing is who names the baby dolphin. Not the mother. Not an auntie dolphin or another group member. Scientists believe the baby dolphin itself comes up with the signature whistle. Like human babies, a baby dolphin plays with sounds throughout its first year. While testing its sound skills, a baby dolphin is doing something amazing. It's creating or figuring out its signature whistle. How or why it chooses its signature whistle is not clear. Studies show that most of the time the signature whistle is nothing like its mother's or group members' whistles.

    When the baby dolphin is about a year old, its signature whistle is set. It repeats it often so the other dolphins learn to recognize it.

    Deciphering(破译) dolphin names is just the beginning of figuring out what dolphins communicate about. Do they chat about sharks? Discuss the tides? Maybe they even have a name for people. Someday scientists are to decipher the rest of dolphins' communication.

    For many of us, talking about money is embarrassing, especially revealing our income and spending habits in public. So it's no wonder that seeking investment advice from computer program is so popular.

    Consultancy firm Accenture found that 68% of global consumers would be happy to use robot-advice to plan for retirement, feeling it would be faster, cheaper, and fairer than human advice. “Many of our customers say they feel awkward in face-to-face meetings, preferring an online experience where they don't feel nervous,” says Lynn Smith, a director of robot-advice firm Wealth Wizards. So how does robot-advice work and is it really any better than traditional financial advice?

    Robot-adviser firms use algorithms (算法) to analyse your financial situation and goals and then work out an investment plan to suit you. Basically, you answer lots of questions online about your income, expenses, family situation, attitude to risk and so on, and then the algorithm allocates (分配) your savings to a series of investments, from index funds that aim to imitate a particular stock market index or sector, to fixed-income bonds.

    Robot-advice is certainly growing in popularity. But are we really happy to give up the human adviser completely? “No” is the short answer. Accenture finds that a significant proportion of us still want human interaction, particularly when our finances are complex. “When a customer needs advice surpassing a number of different regulatory regimes, human advice will be required, says John Perks, managing director of life and pensions at UK insurer LV, which launched its Retirement Wizard robot-advice service two years ago.

    The truth is that only about a quarter of funds managed by clever humans overcome the market as a whole, so when you take into account the much higher management fees you pay for that kind of service, the performance difference is likely to be marginal (微不足道的) for most of us.

    The robots may be coming, but in this case at least, they seem to be on the side of the small investor trying to save for a comfortable retirement.

    On a flight from Dallas, Texas, to Cincinnati, Ohio, to visit a friend in 2013, event planner Paige Chenault daydreamed about the grand birthday parties she'd throw for her daughter one day. (Paige was five months pregnant at the time.) Then, flipping through a magazine, she saw a photo of an impoverished Haitian boy, skinny. "I thought, this kid has nothing," Paige says.

    The image stayed with her, and she resolved to do something to help. "I decided I would use my talents to throw birthday parties for homeless kids," Paige says. For the next four years, Paige and her husband, Colin, took time out from parenthood to visit shelters to determine how best to pull off the parties.

    Finally, in January 2017, Paige launched the Birthday Party Project, a nonprofit organization, and recruited friends and family to help decorate Dallas's 75- occupant Family Gateway Shelter with balloons and streamers, celebrating the birthdays of 11 boys and girls, with 60 more homeless kids in attendance. "That first party was better than I could have ever imagined," says Paige.

    Now Paige and her staff of three paid employees work with regional volunteers to plan monthly themed parties at 15 shelters across the country, some of which house abused or abandoned kids. Each child celebrating a birthday that month gets a $30 gift, a decorative place mat, and an individual cake or cupcake.

    One of Paige's favorite parts of each party is when the kids make a wish and blow out the candles. "They rarely get a chance to dream big," says Paige.

    Her daughter, Lizzie, now seven, often helps out at the parties. Paige says, "The one thing I've always wanted is for my kid to be generous."

    When an ice cube melts, it creates a puddle (水坑). When an ice sheet (冰盖)melts, it raises sea levels. It sounds simple, but scientists have debated for decades whether both the Antarctic and Greenland ice sheets actually were shrinking, and how much that melting contributed to rising sea levels.

    Now, a new study has provided the best evidence of how the polar ice sheets are responding to our warming world. In the study, an international team of scientists looked at 20 years of' data in the ice sheets collected by 10 satellite missions. The team's conclusion: The Greenland and Antarctic ice sheets both are losing ice overall. The researchers also found that between 1992 and 2011, melt water from those shrinking ice sheets caused sea levels to rise by about 11 millimeters.

    Over the 19 years studied, the Greenland ice sheet lost 2.7 trillion metric tons of ice. The Antarctic ice sheet also shrank by about 1.3 trillion metric tons. Previously, some scientists disagreed whether the Antarctic sheet, the largest mass of ice in the world, was shrinking or growing or neither.

    While the Earth is warming overall, the effect of climate change varies from region to region. Over the last 15 years, for example, scientists have something disagreed over how climate change has affected the polar ice sheets. Many studies found that the sheets lost a lot of ice and that not enough snow fell on the sheets to compensate for the loss. But other studies found that the loss of ice was balanced by the gain in snowfall.

    Richard Alley, a glacier scientist at Penn State University, said that many of those studies looked at different areas, and over different time periods. In addition, the studies didn't all use the satellite data in the same way. Those differences made, it difficult to compare the results.

    The data in the new study matched time periods and areas. The study also combined measurements from kinds of satellites.