The ‘Well of Hell,’ fossil footprints | 5 STORIES

On this week’s episode: Cavers descend to the bottom of Yemen’s “Well of Hell, one in two children in the U.S.have detectable levels of lead in their blood, the ability of coral reefs to provide food, jobs and climate protection drops by half, a ‘drowning’ sculpture sparks conversations on sustainability and newly-discovered fossil footprints show earlier humans arrival in North America.