The Bronze Age had the first large urban centers, powerful kingdoms and armies, writing, and trade routes across vast areas. What led to the collapse of the city-state entities and the end of the Bronze Age? Possibly a perfect storm of uncontrollable factors that are still being researched.

Heart disease is the number one cause of deaths worldwide, killing more than eight million people each year. Cardiac infarction, more commonly known as a heart attack, can happen without warning, killing heart muscle cells immediately. Even if the patient recovers, the damage to their heart may not.
But there are researchers frantically working to change that. Meet the people inventing the future of cardiac health, from new ways of imaging the body, to the possibility of 3D printing a functioning heart.

Researchers discuss mythic ancient treasure and curses including King Solomon's Ring, lost Aztec treasure, and the Omphalos.

Dr Chris van Tulleken, Dr Hannah Fry and Michael Mosley examine the latest research and explore some of the big questions about Covid-19 and the pandemic it has created. Michael visits the UK government's high-security laboratory Porton Down, where vaccines are being tested. He also uncovers what the experience of the 2002 SARs epidemic reveals about this one. Both were caused by coronaviruses, but certain key changes to today's virus have allowed it to infect the world, where SARs was contained.

Few sounds are more beautiful or moving than the underwater songs of the humpback whale. Male whales compete with their songs, which often last for 10 minutes at a time, and can be repeated for hours on end. Whales separated by thousands of miles of sea will sing almost identical songs. Researchers have found that the songs change throughout the breeding months, following a mysterious pattern repeated across the waves. Whales also use sound to hunt. To catch herring, humpback whales release a stream of bubbles to form a shimmering, circular fishing net. Emitting a repetitive loud scream, they scare the fish into a tight ball, then lunge out of the water to swallow the shoal whole. Now it seems that the long-held image of the gentle giant must change to one of a ferocious and opportunistic hunter.

Moral psychology isn't always an easy thing to study. Experiments that actually puts people in what feels like a real scenario may get realistic results, but researchers must always balance the benefits of what we could learn with the safety and well-being of the people they study. Often what we learn from moral psychology experiments doesn't make humans look good.
We are imperfect creatures. But the more we learn about why and how we make the moral choices that we do, the better we'll be able to tackle difficult questions in the future.