They're two of a kind. 

Two Bolivian titi monkeys made their public debut at the Brooklyn zoo this week, where they share their habitat with two saki monkeys.

Indigenous to South America, both species are New World monkeys and they have similar ranges in Colombia, Peru and Bolivia. Titis can also be found in northern Paraguay. 

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Residing in the zoo's Hall of Animals Building, the male and female titi monkeys are arboreal and diurnal. This means that they are active during the day and live in trees. Their diet is fruits, leaves and insects — both in the wild and the zoo. 

The Wildlife Conservation Society's Prospect Park Zoo and Queens Zoo are holding celebrations for the Year of the Monkey. Activities at the Queens Zoo are Feb. 20 and 21. The Prospect Park Zoo's activities are Feb. 27 and 28.