Every culture, workplace, group, and family has its norms — its standards, the way things are done. Norms govern everything from relationships to driving to making coffee. But how does something become the norm? On this episode, we explore how things and behaviors become “normal,” and what happens when we challenge those norms. We hear stories about dog crates and why they are embraced in the U.S., but reviled in other countries; why sleeping through the night isn’t as standard as you might think; and how conservation efforts are challenging America’s lobster fishermen to change how they do their work.

Also heard on this week’s episode:

• Sleeping through the night might be ideal — but historians and scientists say it’s probably not natural. Reporter Steph Yin explores how our sleeping habits have changed, and a small subculture that’s exploring alternative ways of getting some shuteye.
• Pediatrician Harvey Karp talks about what got him thinking about infant sleep, and prompted him to write his best-selling book “The Happiest Baby on the Block.”
• The North Atlantic right whale will go extinct if we don’t change our ways, but proposed conservation efforts could put New England’s lobstermen out of business.