Quick Questions gives you the low-down on how oysters turn a tiny bit of gunk into a lovely, valuable pearl. ----------

By 2050, it will take 100 billion land animals to provide the world's population with meat, dairy, eggs and leather goods. Maintaining this herd will take a huge, potentially unsustainable toll on the planet. What if there were a...

Quick Questions gives you the low-down on how oysters turn a tiny bit of gunk into a lovely, valuable pearl.

Hank brings us the strange story of in vitro meat - muscle tissue grown in laboratories with the hope that someday we will eat it.