This is MORNING EDITION, from NPR News. Good morning. I'm Renee Montagne.
DAVID GREENE, HOST:
And I'm David Greene.
For months now, the Obama administration has promised to reveal more about America's secret drone program, and today could be the day. The president will speak this afternoon at the National Defense University, and he's planning to discuss America's fight against terrorism. He is expected to address everything from drones to the prison at Guantanamo Bay.
This model of a molar shows color-coded barium banding patterns that reveal weaning age.
Credit Ian Harrowell, Christine Austin, Manish Arora / Harvard School of Public Health
Top: Lines on a 100,000-year-old Neanderthal tooth mark the passage of time. Bottom: The distribution of barium shows dietary transition: low barium before birth (1), high barium during breast-feeding (2) and falling barium as the Neanderthal transitions to a mixed diet (3).
Credit Alyson Hurt, Adam Cole / NPR / Christine Austin / Westmead Centre for Oral Health
Our closest relatives, chimpanzees and gorillas, breast-feed their offspring for several years. Some baby orangutans nurse until they are 7 years old.
But modern humans wean much earlier. In preindustrial societies, babies stop nursing after about two years. Which raises the question: How did we get that way? When did we make the evolutionary shift from apelike parenting to the short breast-feeding period of humans?
This is MORNING EDITION, from NPR News. I'm Linda Wertheimer.
DAVID GREENE, HOST:
And I'm David Greene. We now know the tornado that struck the city of Moore, Okla., on Monday was an EF5, with winds over 200 miles an hour. That designation is the strongest possible rating for a tornado. Federal, state and local teams are on the ground this morning, cleaning up debris and tending to survivors. But there is little - if any - chance of finding any more survivors; that, according to the fire chief in Moore.
Well, our wings have been clipped by some listeners. Yesterday, we told you about how some scientists in Canada saw their research crops destroyed by geese. We used the term Canadian geese. Listeners like Frank Kohn said we got that wrong.
FRANK KOHN: They're not Canadian geese. They're Canada geese because they don't hold passports, as far as I know, and it's not a nationality. It's a species name.
Here's some news for travelers. If you can't afford - or don't want to pay the price for - a hotel room, maybe you've used the cheap lodging site Airbnb. If so, you have to take New York City off your list. The popular website has suffered a major setback in court. A judge in New York ruled that an Airbnb user in Manhattan violated local laws when he rented a room to an out-of-towner.