Biden toughens Covid vaccine rules

Millions of workers will be required to be vaccinated as the president faces pressure to combat a surge in cases.

How some animal species are evolving far more rapidly than expected - and why climate change is the likely reason.

And we hear about the Ig Nobel awards for unusual scientific research that makes us laugh, then think. This year's winners include a team investigating whether having a beard decreases your chance of being punched in the face, and another which asked if countries with overweight politicians are more corrupt.