Why does Jacob Zuma giggle in parliament?

Why does Jacob Zuma giggle in parliament? Antimatter and Dark Matter; why snails like to eat cigarette filters; rusty water cisterns; why tupperware stays wet after dishwashing; cyanobacteria in water courses; and how gravity works. Plus, news of the antibiotic apolcalypse: evidence of human carriage with bacterial strains resistant to the antibiotic colistin secondary to farm use. Dr Chris joins Redi Thlabi to answer your burning science questions...