The canopies of Costa Rica s most visited national park wriggle with playful capuchin monkeys leaping between trees and scurrying down branches. Momma monkeys lag behind carrying newborns on their backs while off in the distance the sound of an agitated howler monkey booms through the forest. It s just another day in Manuel Antonio National Park, home to more than 100 mammal species and Costa Rica s last refuge for the endangered titi monkeys.