Greetings from the Great Barrier Reef! I’m riding on a sailing boat with some relatives as I write this. We’re diving here all next week. The reef is located in the Coral Sea that is off the northeast coast of Australia.

The reef is made up of many corals. Corals are very hard and made of many tiny animals called “polyps” that look like underwater flowers. The corals need help to eat. They have a special relationship with other small animals, “algae” (藻类), that take in sunlight and make energy for the coral. It’s the algae that give color to the corals. Because algae need sunlight, the corals are very close to the surface of the water.

Together, the many corals create a magical environment. They make a home for the animals that live in the sea. When I went diving the other day, I saw all types of different animals-dolphins, turtles (海龟) and sea snakes. I was surprised at being able to see some fish I see only in movies, like clown fish (小丑鱼). As I am diving, I can feel the spirit of this magical place. It seems that these animals aren’t surprised to see me. Maybe they think I’m another fish!

Sadly, according to scientists, the Great Barrier Reef is dying because the water is getting warmer due to global warming. As the ocean gets warmer, the algae that live in the corals are cut off from the food they need for making energy. As a result, they leave the corals, and the corals die and lose their color. We see many dead white corals when we dive. We need to stop global warming and keep the water from getting hotter!

See you soon,

Gloria

【推荐2】A research paper recently reported that the Chinese paddlefish (中华鲟) — one of the world’s largest freshwater fish — has been declared extinct.

Scientists say the Chinese paddlefish and its close relatives have been around for at least 200 million years. The species, reaching up to seven meters in length, survived unimaginable changes, such as the mass extinction that killed the dinosaurs. But there’s one phenomenon this ancient species, sometimes called the “panda of the Yangtze”, could not survive humans.

Their huge size and plentiful flesh made them a popular target for fishermen and a welcome addition to inner tables in China. In the 1970s, 25 tons of paddlefish were harvested per year on average.

But the construction of the Gezhouba Dam on the Yangtze forever changed the Yangtze River habitat of paddlefish, because it was constructed without a fish ladder or sideway and cut off the paddlefish from their only breeding (繁殖) grounds upstream. Populations of the fish continued to decrease after the completion of the dam in 1981, but nobody had yet figured out how terrible the situation was. As is often the case, there can be a significant delay between major disturbances and their consequence. The researchers say the fish had become functionally extinct by 1993, meaning there were not enough fish to meaningfully reproduce.

Pan Wenjing is an ocean expert with Greenpeace East Asia. She told The Associated Press the extinction of the Chinese paddlefish was “a huge loss” for nature. She said the development confirms that the Yangtze River is experiencing major environmental damage.

“The ecosystem of the Yangtze River is close to its breaking point due to human activity in past decades.” Pan said. “The paddlefish’s extinction should serve as a wake-up call to protect other freshwater species. Moving forward, we need to balance the needs of humans with the needs of life in rivers and seas. Humans should not live alone on this planet.”

【推荐1】Bill Gates and the president of General Motors have met for lunch, and Gates is going on and on about computer technology. “If automotive technology had kept pace with computer technology over the past few decades, you would now be driving a V-32 instead of a V-8, and it would have a top speed of 10,000 miles per hour,” says Gates. “Or, you could have an economy car that weighs 30 pounds and gets a thousand miles to a gallon of gas. In either case, the sticker price of a new car would be less than $50. Why haven’t you guys kept up?”

The president of GM smiles and says, “Because the federal government won't let us build cars that crash four times a day.”

Why is that funny (or not funny, as the case may be)? Human beings love to laugh, and the average adult laughs 17 times a day. Humans love to laugh so much that there are actually industries built around laughter. Jokes, sitcoms and comedians are all designed to get us laughing, because laughing feels good. For us it seems so natural, but the funny thing is that humans are one of the only species that laughs. Laughter is actually a complex response that involves many of the same skills used in solving problems.

Laughter is a great thing — that’s why we’ve all heard the saying, “Laughter is the best medicine.” There is strong evidence that laughter can actually improve health and help fight disease. In this article, we’ll look at laughter — what it is, what happens in our brains when we laugh, what makes us laugh and how it can make us healthier and happier. You’ll also learn that there’s a tremendous amount that no one understands yet.

【推荐2】A recent experiment proves that bees can save time and energy when they fly around to different flowers.

Dr Nigel Raine, from the Royal Holloway University of London, has always been interested in finding out why animal behave like they do. He is also interested in bees. It was not a surprise when he and some other scientists from Queen Mary University of London discovered that bees can quickly solve a problem that takes computers many days.

Flowers make pollen (花粉), and when bees visit them, they carry the pollen to other flowers. The plants need the pollen to make seeds that will grow. Dr Raine notes that we get a lot of our food from plants, so it is important to know how the bees move around and take the pollen between flowers. The scientists wanted to examine the journey that the bees take and how they save energy when they do this. They completed the experiment on the roof of Queen Mary University, using artificial flowers and a large amount of nectar, a sweet liquid produced by flowers. They taught one bee to visit all the flowers in one place at the same time. When the bee got to know the location of the flowers well, they saw how it flew around and returned home with the nectar. After this, they changed the locations of the flowers. The scientists thought the bee would follow the route it knew already. This would mean that it followed a longer route than it needed to, and so it would use more energy. They watched the bee carefully as it travelled between the flowers in their new location, and they made notes. But in the experiment, the bee changed its route and flew a shorter distance.

The problem that the bee solved is similar to a maths puzzle called the ‘travelling salesman problem’. A salesman who goes to different places to sell things wants to travel the shortest distance. But he has to calculate the length of many possible routes to know which one is the shortest. A computer can calculate this but the experiment shows bees can do the same calculation quickly with a tiny brain. Scientists are very interested in how they do this. It would help us to understand how pollen is moved around. In addition, if they find this out, it could help us to improve communication networks. This might help humans to reduce traffic jams when there is an accident, for example.

【推荐2】The Mars 2020 rover(02W), which sets off for the Red Planet this year, will not only search for traces of ancient life, but pave the way for future human missions, NASA scientists said Friday as they introduced the vehicle.

The rover has been constructed in a large, sterile room at the Jet Propulsion Laboratory in Pasadena, near Los Angeles, where its driving equipment was given its first successful test last week.

Shown to invited journalists on Friday, it is scheduled to leave Earth in July 2020 from Floridas Cape Canaveral, becoming the fifth US rover to land on Mars seven months later in February.

“It's designed to seek the signs of life, so we’re carrying a number of different instruments that will help us understand the geological and chemical context on the surface of Mars,” deputy mission leader Matt Wallace told AFP.

Among the devices on board the rover are 23 cameras, two “ears” that will allow it to listen to Martian winds, and lasers used for chemical analysis.

Approximately the size of a car, the rover is equipped with six wheels like the former US rover, Curiosity, allowing it to travel along rocky land.

Speed is not a priority for the vehicle, which only has to cover around 200 yards(180 metres) per Martian day -approximately the same as a day on Earth.

Fuelled by a tiny nuclear reactor, Mars 202(has seven-foot-long(2 metres) articulated arms and a drill to crack open rock samples in locations scientists identify as potentially suitable for life.

We are hoping to move fairly quickly. We'd like to see the next mission launched in 2026 which will get to Mars and pick up the samples, put them into a rocket and finally bring them back to the Earth, "said Wallace. NASA’s Mars 2020 will remain active for at least one Martian year, which is around two years on Earth.