Dolphins have unique whistles for their friends, and more breakthroughs

A gut worm does something helpful for once; the flu gets decoded; and crows can get confused during breeding season.

Dolphins’ whistles identify their pals

In the animal kingdom, it’s common for creatures in the same social circles to adopt similar calls. For years researchers assumed dolphins did the same. But as Stephanie King, a biologist at the University of Western Australia, spent time recording male bottlenose dolphin vocalisations in Shark Bay, she realised that individuals were using unique whistles, even within tight-knit groups. King deduced in a recent study that these calling cards, or “names”, help dolphins keep track of “who their friends are, who are their friends’ friends, and who are their competitors”, she says. Next King will use these calls to learn how male dolphins form and maintain individual social relationships. A lot of this feels familiar to her. “There are a number of striking similarities between human and dolphin societies”, she says. –Nina Strochlic

Lost in transcription

The flu’s genes are written in RNA, a chemical code like DNA but harder to read. To simplify, scientists can “rewrite” RNA into DNA—but they lose information in the process. Now there’s a way to read flu genes directly: When RNA is passed through a tiny pore in an electrified membrane, resistance in the current helps identify the molecules and genes. –Theresa Machemer

PHOTOGRAPH BY GOPAL MURTI, GETTY IMAGES

Last rites for crows

Crows are one of the few animals known to react strongly when one of their own dies, says researcher Kaeli Swift of the University of Washington. After a death, the flock gathers and may caw loudly, she says; it seems to be a way for them to learn about dangers they should avoid. Most don’t get too close to their dead peer—unless it’s breeding season, when hormones can affect their behaviour. –Lori Cuthbert

PHOTOGRAPH BY JOEL SARTORE, NATIONAL GEOGRAPHIC PHOTO ARK

As the worm turns

In less developed nations this helminth lives in human intestines—helpfully, says a report in Science. The worm promotes a microbiota that reduces bacteria linked to inflammatory bowel disease and other illnesses. Without the worm, bad bacteria can thrive. –Lori Cuthbert

PHOTOGRAPH BY DENNIS KUNKEL

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