Sandy, a young Chinese Singaporean, is fluent in English and Mandarin, the official “mother tongue” of Chinese Singaporeans. Her grandmother spoke little of either.

Their language barrier was the product of decades of linguistic(语言的) engineering. English has been the language of teaching in nearly all schools since 1987, to promote Singapore’s global competitive advantage. But, depending on ethnicity(种族特点), pupils study a second language-typically Mandarin, Malay or Tamil. In the case of Mandarin, its acquisition has been promoted by the government’s annual “Speak Mandarin Campaign”, started in 1979.

So dialects - Hokkien, Cantonese and Hakka - were disparaged. In the early 1980s television and radio programming in these languages almost disappeared. By the campaign’s own standard, the success is striking. The use of Chinese dialects at home has fallen down from 76% of Chinese households in 1980 to 16% in 2015. Over the same period, the use of Mandarin rose, from 13% of Chinese households to 46%.

In 2015, the 50th anniversary of the nation’s founding was accompanied by a rush of sentimentality over Singapore’s roots. These days officials are a bit readier to tolerate Singapore’s linguistic variety. Meanwhile, younger Singaporeans are embracing former mother tongues. Ski Yeo and Eugene Lee were motivated to found LearnDialect.sg upon seeing an elderly Cantonese-speaker in a nursing home struggle to communicate that she was cold. Health workers have signed up to their courses, while others want to say the right things at family gatherings over the lunar new year.

Smooth balls of ice rolled ashore on a beach in Finland and piled up like a huge bunch of turtles' eggs. But where did these “ice eggs” come from?

Amateur photographer Risto Mattila stumbled upon the strange sight while walking with his wife on Hailuoto Island. The temperature remained around minus 1degree Celsius that day, he said, and the wind blew quickly across the beach. “There we found this amazing phenomenon. There was snow and ice eggs along the beach near the water line”.

The “ice eggs” littered an area the length of about one-quarter of a football field and ranged in size from that of an average chicken egg to that of a powerful soccer ball. Mattila took a photo, noting that he had “never seen anything like this during 25 years around here.” Others came upon the ice eggs, too. “I've never seen this before. The whole beach was almost full of these ice balls,” said Tarja Terentjeff, who lives in the nearby town of Oulu. Another local, Sirpa Tero, told CNN she’d seen snowballs line the shoreline before, but not over such a large area.

“Although it happens once in a blue moon, these ice eggs form similarly to sea glass or rounded stones that wash up on the beach.” said BBC Weather expert George Goodfellow. Chunks(块) of ice break off from larger ice sheets in the sea and either slide to shore on the incoming tide or get pushed in by strong spells of wind at the water' s surface, he explained. Waves buffet(冲击) the ice chunks as they travel, slowly eroding their rough edges into smooth curves. Seawater sticks and freezes to the forming eggs, causing them to grow like snowballs do as they roll across the ground, leaving behind nothing but smooth and shiny “eggs” for curious tourists to happen upon.

Chimps live in a male-dominated society, where most of their valuable partners are other males. However, as young male chimps become adults, they continue to maintain tight bonds with their mothers, a new study finds.

“The dramatic changes of adolescence are difficult for chimps, just like they are for humans,” says Elizabeth Lonsdorf, an expert on primates (灵长动物) at Franklin&Marshall College who was not involved in the study. “Sure enough,” she adds, “their moms remain a key social partner during this time.”

Previous research has shown chimp mothers provide their sons with support that goes far beyond nursing. Young male chimps that are close with their moms grow bigger and have a greater chance of survival. What’s more, losing their mothers after weaning (断奶), but before age 12，gets in the way of the ability of young chimps to win other males and reproduce.

To see whether this bond extends later into life, researchers followed 29 adolescent (9 to 15 years old) and young adult (16 to 20 years old) male chimps at a research site in Kibale National Park in Uganda and observed them from a distance for 3 years. The team found that the young adult males spent less time with their mothers than the adolescents did—26% vs. 76%. As the male chimps grew older and more independent, they began to travel over wider ranges and spent more time away from their moms.

However, when these young adult males happened to be in the company of their mothers, they acted just like the adolescents. They groomed (梳理) their moms just as often and kept track of them. “Many mothers remained the males’ ‘best friends’ or ‘social partners’ they associated with most frequently,” says study co-leader Rachna Reddy from Harvard University.

Such persistent ties are also common in humans after sons leave their mothers and live on their own—especially in tough times, Reddy says. “We really feel what it’s like to not be able to see our mothers when we want to in tough times. The importance of those bonds in our lives and the comfort we get from them have deep evolutionary roots.”