The Amazon is an amazing river. Among the world's longest, with almost 1,000 tributaries, crossing through 6 countries, and covering 1/3 of South America. With its swamplands and seasonal floods, it is almost part of the rainforest: together, these ecosystems of unequaled biodiversity host almost 15% of all known lifeforms. For centuries, it has provided lives and livelihoods to thousands of people. Botanists have noted that the forest was shaped and tamed by native populations who promoted the growth of medicinal and edible species. Their lifestyles are still in tune with nature today.