A look at some unexpected elements of congestion: Why does pollen make so many of us wheezy, and sneezy? What can it tell us about the distant past? Plus, we take a look at what we can learn from the construction and engineering behind aquatic snot palaces. Plus your enemy’s enemy can be your friend – hear about the tiny viruses that invade certain bacteria. Speaking of bacteria, we look at the latest place to hunt for new antibiotics – the fur of a certain animal, and with reports of famine emerging from North Korea, we hear about the scientist who is said to have saved more lives than any other person who has ever lived.