Take a close look at a house cat's eyes and you'll see pupils that look like vertical slits. But a tiger has round pupils — like humans do. And the eyes of other animals, like goats and horses, have slits that are horizontal.
Scientists have now done the first comprehensive study of these three kinds of pupils. The shape of the animal's pupil, it turns out, is closely related to the animal's size and whether it's a predator or prey.
#NPRreads is a weekly feature on Twitter and on The Two-Way. The premise is simple: Correspondents, editors and producers throughout our newsroom share pieces that have kept them reading. They share tidbits using the #NPRreadshashtag — and on Fridays, we highlight some of the best stories.
This week, we bring you three items.
From NPR's South America correspondent, Lourdes Garcia-Navarro:
Originally published on Fri August 7, 2015 3:04 pm
Some days, the french fries are just irresistible. You know it's not the best thing to put in your body, but did that salad really stand a chance after the smell of fried garlic, Parmesan and thyme on crisp potato wedges wafted over to you?
It goes by many names: Delhi belly. Montezuma's revenge. The Aztec two-step.But doctors useone not-so-glamorous term: traveler's diarrhea.
If you're visiting a place this summer with less than ideal sewage disposal — maybe a resort in Mexico or a village in Rajasthan — chances are your GI tract will give you trouble at least once ... maybe twice ... maybe continuously.
Humpback whales don't just sing songs — they compose with the whales around them, singing a song that evolves over time. Scientists didn't know that until they started recording whale sounds in the 1960s and spent years listening. The evolution of this "culture of listening" among researchers is the focus of Morning Edition's weekly summer series,Close Listening: Decoding Nature Through Sound.
The name Hiroshima is so tied to the atomic bomb that it's hard to imagine there were other possible targets.
But in early 1945, the U.S. was still months away from building its first bomb and certainly didn't know what to hit.
"Should it be a city? Should it be a military installation? Should you be just displaying the bomb, without killing anybody?" These are questions that were yet to be decided, says Alex Wellerstein, a historian at the Stevens Institute of Technology.