What On Earth?
S7 | E11 | Airdate: 03/20/2020
TERMITE CITY: When satellites capture a vast swathe of strange mounds in Brazil, botanist Roy Funch heads into the remote interior to investigate. What he discovers astounds the scientist: it's the most extensive bioengineering project by one of Earth's smallest creatures and is millennia in the making. THAMES TIMEBOMB: Aerial images reveal a baffling shipping exclusion zone in the Thames River near London. It is a sunken World War II vessel whose cargo threatens to devastate one of the world's great cities at a moment's notice. SPANISH STONEHENGE: During extreme drought in Spain a receding reservoir reveals a weird circular structure. Some fear it's a sinister legacy of brutal fascist dictator Franco's; analysis uncovers it's an ancient site possibly harboring cannibalism. JET TRAIN: A thin black streak stretches across the French countryside. This is an incredible, ground-breaking engineering project that threatened to revolutionize high-speed travel until it was cruelly sabotaged. POISON PONDS: A bizarre two-toned lake in the Canadian wilderness is engaged in extraordinary experiments combating new aquatic threats to our planet.