Quick tests for COVID, rat hides poison in its fur, neuroscientists see how we see colour, our planet’s climate zones are changing and why the hottest temperatures are in Death Valley

Quirks and Quarks from CBC Radio

Could quick COVID ‘antigen’ tests break the back of the pandemic?;This gorgeous African rat combs poison into its fur to deter predators; Neuroscience suggests that yes, when you see purple, it's the same purple I see; The world's major climate zones - polar, temperate and tropical - are transforming as we watch; Why are the hottest temperatures measured in Death Valley?