Today’s History newsletter examines religion and happiness, how many steps a day you should walk, the lessons of Ötzi the Iceman, how the 1 percent of the 1600s lived ... and the world’s biggest primate. Plus, how a kid, saved from the Holocaust, changed the world.

PHOTOGRAPH BY KARLA GACHET AND IVAN KASHINSKY, NAT GEO IMAGE COLLECTION

In recent years, social scientists have surveyed people around the world to ask how happy they are. In many cases, they’ve found meaningful correlations between people’s self-reported rankings of happiness and whether they take part in organized religious services. Is it a shared sense of purpose or meaning? The social setting? The faith itself?

Related: These are the world’s happiest places 

Also: Ancient religion maintains a foothold—and fervent followers 

PHOTOGRAPH COURTESY THE PROVINCE OF NORTH-HOLLAND, THE NETHERLANDS

PHOTOGRAPH BY ARNOLD NEWMAN 

Arlo Penzias never met the stranger who saved him from the Holocaust. But Penzias grew up to help develop something that changed the world—and won him a Nobel Prize. What was it? 

A. The Apollo 11 lunar landing
B. The Big Bang Theory
C. The heart transplant
D. In-vitro fertilization 

Related: This project traces the ghosts of the Holocaust across Europe  

Today’s Soundtrack: Church, Lyle Lovett  

Thanks for reading today’s newsletter, edited and curated by David Beard and produced by Amanda Williams-Bryant. Catch our latest Photo of the Week—and sign up here to get our future adventures in your inbox.