This enigmatic forest once stretched along the coast for thousands of kilometres. Now there is only 7% left. Yet it is still home for many remarkable animals. Muriqui are the largest monkeys in South America. These very rare, highly social creatures greet each other with hugs - the closer the friendship, the more intense the hugs. Great dusky swifts fly through the tumbling waters of the mighty Iguaçu Falls to build their nests on the slippery rock faces behind the curtains of water. Coatis are curious looking creatures with their long flexible noses and banded tails, making them quite comical. But appearances can be deceptive, and coatis are efficient hunters. They are also very social, living in all-female gangs that are composed of sisters, mothers and aunts. The females support one another in their day-to-day lives, keeping a watch out for predators. Blue manakins are also social, but in a completely different way. In the depths of the forest, the males of these startlingly colourful birds work as a team to court a female. Like miniature circus performers they jump and bounce on a branch, one after the other, to excite their audience. Only the lead artist gets to carry out the last act.