Fernando Colchero, Roland Rau, and Susan Alberts describe the relationship between lifespan equality and average lifespan.

How Sherpas adapt to high altitudes

Welcome to Science Sessions, the PNAS podcast program. Listen to brief conversations with cutting-edge researchers, Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in PNAS, plus a broad range of scientific news about discoveries that affect the world around us.