There’s a lot that can be conveyed in a handshake, a kiss, or a hug. Throughout history, such a greeting was used to signal friendship, finalize a business transaction, or indicate religious devotion. But touching strangers can also transmit other, less beneficial shared outcomes—like disease outbreaks.

As fears about COVID-19, or coronavirus, mount, France has warned its citizens to pause their famous cheek kisses, and across the world business deals are being sealed with an elbow bump. But with histories tracing back thousands of years, both greetings are likely too entrenched to be so easily halted.

A popular theory on the handshake’s origin is that it began as a gesture of peace. Grasping hands proved you were not holding a