The pygmy marmoset, also known as the pocket or finger monkey, is the smallest monkey in the world (that we know of). This monkey can be found in the Amazon rainforest of Colombia, Ecuador, Bolivia, Peru, and Brazil.
This second type can be found in Bolivia's Amazon region, almost always near rivers. Pygmy marmosets are not an endangered species in Bolivia.
Pygmy marmoset monkeys are about 5 inches (13 cms) tall and they eat tree sap, grasshoppers, and other small insects. These tiny monkeys communicate by making high pitched clicks. The way they talk to each other is called "babbling".
To attract a female or to gain territory, the male pygmy marmosets will raise their ear tufts, arch their backs, and grimace while eyeing each other and displaying their genitals.
Unfortunately for you monkey lovers out there, while they are very cute they are not good pets because they bite and throw their feces (poop) if they feel threatened. They have very specific dietary needs as well and in the wild they can live from 15 up to 20 years of age.