Season 4

Hardly anyone can escape the fascination of crashing masses of water. But waterfalls are much more than that: To this day, they continue to puzzle researchers: How exactly do waterfalls form? Which species have specialized in this particular ecosystem? And what do they mean for the animals and plants in the surrounding area? Marine biologist Uli Kunz takes us to the most impressive waterfalls on earth, the oldest, the largest, the most beautiful and the most mysterious. He explores the mighty Victoria Falls on the Zambezi River and answers questions that every visitor to the falls has probably already asked: Do fish actually fall down the waterfalls all the time, and if so, do they survive the fall?

Deltas are among the most diverse habitats on earth. Marine biologist Uli Kunz guides us through these fascinating intermediate worlds of land and water and gets to the bottom of phenomena: How do animals and plants manage to exist in both fresh and salt water? Why is the species richness in deltas so enormous? And what forces shape deltas? In Mozambique, Uli Kunz dives for bull sharks – the only shark species that can live in both salty and fresh water. In Tasmania, Australia, he explores one of the most unusual bodies of water on earth: in Bathurst Harbour, deep-sea creatures live in water less than ten meters deep. And on the Amazon, he finds out what primordial sea creatures are doing in the middle of the rainforest and how predatory cats have learned to fish in the sea.