In 2019 a strong typhoon devastated parts of Japan. Viewers of the Darwin program wrote to us expressing concern for the wildlife we profiled in an earlier episode inhabiting the banks of Tokyo's Tama River. Can the "Tamazon" ecosystem still support the deer, boar, badgers and weasels? Our cameras indeed revealed unparalleled destruction ... but also rejuvenation. Waterways have changed course. Sandbars have shifted. And the wildlife? Though challenges remain, the footage paints a rosy future.

The male Japanese stream frog sports some surprising sumo and wrestling moves. But watch this Prince Charming's way with the ladies. During mating season, he'll clutch a female in a vice-like grip and ride piggyback as she makes her way toward the spawning grounds. But it's no pleasure cruise. The long river route is full of fast-flowing rocky turns and waterfalls. No matter the hazard, he will not let go. But a new threat awaits: the bevy of anxious bachelors who don't accept no for an answer!

A rosy red nose and bright blue cheeks ... a kabuki actor? No, it's the mandrill! For males, that pretty face plays a key role in their quest for dominance. After all, their troops, called "hordes," can number into the hundreds. The Darwin team tracks 1 horde featuring 3 strong adults vying for the alpha male role. The current leader's color is fading as he ages; another is young, brash and a bit violent; while the third, the largest of the trio, is quite timid but a hit with the ladies!