What does an oceangoing titaness do after she has the lost the ability to bear young?

Well, for starters, she goes on living — sometimes past age 90, while male killer whales older than 50 are dying off in droves.

But she does more than survive, says a new study: She “leans in,” becoming an influential leader of younger killer whales, honing the survival skills of her progeny — and their progeny. Published in Current Biology, the research finds that among killer whales, females beyond their reproductive years become habitual leaders of collective movement — generally foraging movement — within their pods. Itoffers the first evidence that in certain species and circumstances, females who live well beyond their reproductive years “act as repositories of ecological knowledge.”


Beware of smiles, gender inequality

Benevolent sexism makes men more smiley when they interact with women, and that’s bad news. Men who put women on a pedestal may be the wolves in sheep clothing hindering gender equality.

A small study examining nonverbal cues in interactions between men and women finds that men who have high ratings of “benevolent sexism” — attitudes toward women that are well-intentioned but perpetuate inequality — finds that smiling and other positive cues increase when this kind of sexism is prevalent.

“Basically, the argument is that these two properties — hostile sexism and benevolent sexism — work together to maintain inequality,” said lead author Jin Goh, a graduate student at Northeastern University. Most people think of sexist men as being dominant aggressors. But other men believe that women should be treated with kindness, but still don’t see them as being capable of achieving the same things as men.


Fastest star sent out by partner

Hurtling through the galaxy at about 1,200 kilometers per second is a compact helium star with an unusual origin. Unlike most high-velocity stars, scientists say this one — thought to be the fastest unbound star in the galaxy — was set in motion not by the black hole at the center of our galaxy, but by a former companion.

Originally, star US 708 was a red giant star, and its partner was a white dwarf. Once their orbit began to tighten, helium from the red giant was transferred to the white dwarf, said a study published in Science. Eventually, the helium ignited, causing the white dwarf to explode, sending US 708 into space.

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