1 . MEXICO CITY, April 1（Xinhua）——Discoveries at the legendary Sanxingdui ruins in southwest China show that the region’s ancient Shu state civilization shared similarities with the Maya, according to the director of the Chichen Itza archaeological site, Marco Antonio Santos.

The Sanxingdui ruins, located in the city of Guanghan, about 60 kilometers from Chengdu, belonged to the Shu Kingdom that existed at least 4,800 years ago and lasted more than 2,000 years. China announced on March 20 that archaeologists uncovered gold, ivory and jade objects dating back about 3,000 years in six sacrificial pits.

Santos told Xinhua that the bronze-made remains of trees buried at the ruins of the Shu Kingdom recall the Maya’s sacred ceiba tree, which symbolized the union of heaven, earth and the underworld for the civilization that flourished in Mesoamerica. “They are very important similarities.” said Santos, stressing that “the representations of trees in both cultures provide us with a symbolism that is very similar”.

“One notable feature of the recent discoveries at Sanxingdui was the interdisciplinary（跨学科的）work and technology applied by teams of Chinese archaeologists.” said Santos. “The technology allowed the unearthing of artifacts as fragile as silk remains, which other types of less careful excavation methods would not have been able to manage.” he said. “Cooperation between Chinese and Mexican archaeologists could benefit projects in the Maya world, where the rainy climate and humidity are problematic for the conservation of objects.” said Santos.

“Every time our cultural knowledge increases, regardless of whether we speak one language or another, what it shows us is that we continue to be sister cultures, and, therefore, the exchange of such knowledge is fundamental.” said Santos.

2 . Large oceangoing vessels like oil tankers and cruise ships produce noise that travels long distances underwater. That audio pollution can disturb the sounds that marine mammals, fish and other animals use to communicate.

Emily Carter, a sensory ecologist from University of Exeter wondered whether ship noise might also be harmful to animals that don’t rely on sound for communication. For example, young shore crabs that use camouflage (伪装) to hide from predators. “So they can actually change their color to match whatever it is that they’re sitting on, basically to make it harder for predators to find them.” Carter explained.

She suspected that stress from ship noise might affect the change process. To find out, she and her colleagues collected shore crabs with dark shells and brought them back to the lab. They placed the crabs in tanks full of white small stones. An underwater speaker in each tank played quiet natural sounds at all times. One group of crabs also heard loud natural sounds every hour. But another group was subjected to hourly recordings of large ships.

Carter says shorebirds, which eat the crabs, can see UV light, so she used ultraviolet (紫外线) photography to determine how well the crabs blended into their new habitat over time.

“Through the eyes of a shorebird — so through bird’s perspective — were they camouflaged? Weren’t they camouflaged? How obvious would they be?”

After eight weeks, the crabs that heard only natural sounds had become much lighter and were well camouflaged. But the ones that were exposed to the ship noise didn’t change color as much. And then, as a result, they weren’t as camouflaged at the end of the experiment. So they’d be much more manifest to predator.

Carter says the stress caused by ship noise may affect hormones that regulate color change in crabs or destroy the energy needed to make the change efficiently. The research not only puts a spotlight on the unintended consequences of noise pollution, but is a reminder that too much stress isn’t just bad for people — it can also be deadly to wildlife that needs some peace and quiet.

3 . Most people would describe a dollar millionaire as rich, yet many millionaires would disagree. They do not compare themselves with teachers or shop assistants but with the other parents at their children's private schools. To count the number of rich people in the world, however, an arbitrary cut-off point is needed, and $1 million is as good as any. Capgemini defines anyone with investable property of $ l million or more as a “high-net-worth individual”. By this measure the planet has about 10 million millionaires. According to Capgemini and Merrill Lynch, a bank Credit Suisse, another bank, uses a less strict definition: a millionaire is anyone whose net assets exceed $1 million. That includes everything: a home, an art collection, even the value of an as-yet-inaccessible pension. The Credit Suisse "Global Wealth Report" estimates that there were 24.2 million such people in 2015, about 0.5% of the world's adult population. By this measure, there are more millionaires than there are Australians. They control $69.2 trillion in property, more than a third of the global total.

How did these people grow rich? Mostly through their own efforts. Only 16% inherited their stash. The most common way to get rich is to start a business: nearly half (47%) of the world's wealthy people are entrepreneurs.

You do not have to be a genius to build a million-dollar business, but it helps if you are intelligent and extremely hard-working. In their book “The Millionaire Next Door”, Thomas Stanley observed that a typical American millionaire is surprisingly ordinary. He does not live in the fanciest part of town — why waste money that you can invest? And his tastes are so plain that you can barely tell him apart from his neighbours. He buys $40 shoes, and his car of choice is a Ford.

Another 23% of the world's millionaires got rich through paid work, estimates Capgemini. A few vault easily over the million-dollar bar. Gregory Maffei, the boss of Liberty Media, earned $87,095.882 in 2010. The median pay for chief executives at the 456 largest publicly quoted firms in America was $7.23 million, according to the Hay Group, a consultancy. But the vast majority are skilled professionals or managers who have been careful with their money. An dentist in America makes about $200,000 a year. He may leave medical school heavily in debt, but after a lifetime of earning, saving and investing he can probably amass $1 million.

5 . With the infection being brought under control, more and more galleries and museums are reopening. While many museums have been putting exhibitions online, visitors still prefer to enjoy works of art in person. Here are four major art exhibitions that are held offline.

The Palace Museum (Dec. 10—Feb. 15)

The exhibition, Everlasting Splendor which is being held in the Meridian Gate Galleries, marks the 600^th anniversary of China’s imperial palace. Over 400 cultural relics are displayed at the exhibition, reflecting the history of the Forbidden City’s construction, the development of its layout, and how it has been protected and restored in the past decades.

The National Museum of China (Jan. 4—Mar. 29)

The exhibition, A Sail Over Miles, offers a brief review of the ancient Silk Road in ceramics (陶瓷). It guides visitors through the manufacturing, export and shipping routes from the Tang Dynasty to the Qing Dynasty with over 300 ceramic relies, including a pot dug from Nanhai No 1, a Chinese cargo ship dating back more than 800 years. The exhibition also shows Japanese, Korean and British ceramics, reflecting the influence of China’s porcelain-making techniques in local industries.

The Capital Museum (Jan. 1—Mar. 30)

The Capital Museum is to host Man of Infinite Refinement: Special Exhibition on the Paintings and Calligraphy of Su Shi, a calligraphy and painting exhibition on the legacy of Su Shi, an iconic figure of ancient Chinese literature and fine arts. The 78 exhibits on display spans from the Northern Song Dynasty through recent history and cover a range of media, including calligraphy, paintings, documents and rarely seen books.

The National Art Museum of China (Nov. 30—Feb. 10)

On show are nearly 300 objects, including paintings, calligraphy works, carved seals, manuscripts, letters and books. Donation of Rong Geng not only reflects his academic accumulation over the years, but forms the basis for his becoming such a well-rounded scholar in the area of Chinese cultural traditions.

Rong Geng (1894—1983), a scholar of Chinese paleography, educator and connoisseur of antiquities, is little known to the general public. However, his extensive studies of ancient Chinese writings and his former collection of archaic oracle bones and bronzes continue to enrich people’s cultural life. In his lifetime, Rong donated to the State nearly 200 bronze objects, all of which are now housed at numerous public museums and universities.

7 . TRAVEL ADVISORY

Here are a few things you should know before you take off on your next trip.

Frontier Airlines Face Covering Requirement

As required by federal law, the Centers for Disease Control (CDC) Order and Transportation Security Administration (TSA) Security Directive, all passengers and employees must wear a face covering over nose and mouth throughout the Frontier travel experience including at ticket counters, gate areas, baggage claim and onboard all flights. Face coverings are not required for children under the age of 2. Face coverings must fit snugly(紧密地) over your nose and mouth and be secured under the chin. Not wearing an approved face covering is a violation of federal law and you may lose future travel privileges on Frontier.

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Know Your Travel Policy

CDC issued an Order on January 12, 2021(effective since January, 26, 2021) requiring proof of a negative COVID-19 test or documentation of having recovered from COVID-19 for all air passengers arriving from a foreign country to the US.