Paul Saffo: The Illusion of Scientific Progress

The breathtaking advance of scientific discovery has the unknown on the run. Not so long ago, the Creation was 8,000 years old and Heaven hovered a few thousand miles above our heads. Now Earth is 4.5 billion years old and the observable Universe spans 92 billion light years. Pick any scientific field and the story is the same, with new discoveries—and new life-touching wonders—arriving almost daily. Like Pope, we marvel at how hidden Nature is revealed in scientific light. Our growing c...

 Evolution of Lactose Tolerance

One case involves our ability to digest lactose, a sugar found in milk. An enzyme called lactase breaks down this sugar into the more easily absorbed sugars glucose and galactose. We are born with the ability to digest milk, of course, for that’s always been the main food of infants. But after we’re weaned, we gradually stop producing lactase. Eventually, many of us entirely lose our ability to digest lactose, becoming “lactose intolerant” and prone to diarrhea, bloating, and cramps a...