In this two-hour special, renowned paleontologist Kirk Johnson takes us on an epic adventure through time at the polar extremes of our planet. Following a trail of strange fossils found in all the wrong places—beech trees in Antarctica, hippo-like mammals in the Arctic—Johnson uncovers the bizarre history of the poles, from miles-high ice sheets to warm polar forests teeming with life. What caused such dramatic changes at the ends of the Earth? And what can the past reveal about our planet's climate today—and in the future?

Worshipped as a goddess, condemned as satanic, and spun into a stunning array of breeds, cats have long fascinated humans. But did we ever really domesticate them? And what can science tell us about our most mysterious companions?