Pygmy Marmoset - The Smallest Monkey
These are the smallest monkeys in the world although there are some primates that are bit smaller (pygmy mouse lemurs and pygmy tarsiers). The body weight of adults in the wild averages only 4 ounces! You can see from the picture above why they are often called "finger monkeys." They are about 5 inches (13cm) tall not including the tail (the tail can be even longer than the body). Which means they might be hard to observe in the wild as they tiny enough to be high-up in the trees on small branches. Up there, they have to be on the lookout for birds of prey and that is why they usually don't go all the way up to the very top of the forest canopy. To help them watch for potential threats their heads can rotate a full 180 degrees. They also possess sharp claws for holding on to the trees and they are able to jump more than 16 ft or 5m. Quite a distance for such a small monkey.
These pygmies inhabit the Amazon rain forest in Colombia, Ecuador, Bolivia, Peru and Brazil. They enjoy a view of the water and prefer forests that may have a riverfront view or else flood-plain. They scramble about like squirrels in the deep rainforest and drink the sap of trees. Since they are so tiny they can climb very high up in the trees on slender branches to find untapped sources of food - the sap and gum of trees. Ever see gum arabic listed in the ingredients of food products? It is a commercially available exudate from acacia trees that these little monkeys are happy to eat straight without any mixers. To get at the tree sap they gnaw little holes into the trees so that the sap fills up and they can lick it with their tongues. They also like to eat grasshoppers and some other insects when available.
Pygmy marmosets communicate by making high pitched clicks, squeaks, whistles and trills. In fact they can make noises that are so high pitch that humans can't even hear them. They do have a language of sorts, where certain types of calls and squeaks signify danger or other important monkey communications. They also use different calls depending on the distance they need to communicate across.
Male pygmy marmosets may make displays of strength and prowess when confronted by other males and competing for territory. They do this by raising and flattening their ear tufts, arching their backs, grimacing while eyeing each other and displaying their genitals. Females usually give birth to two and sometimes three babies. Everyone in the family group including brothers and sisters may help care for the offspring.
These monkeys are not good pets as they do bite and throw feces. In captivity they are not happy away from their families and are hard to care for. (Also see Monkeys for Sale)
Read about the birth of Abino Pygmy Marmoset Twins