A young pygmy marmoset, the world's tiniest monkey, was born recently at the United Kingdom's Chester Zoo, according to an article in the Liverpool Echo.

These monkeys, though not rare, are quite unusually small. For instance, they grow only to the length of a writing pen (12 cm in height) and the weight of a medium-size chocolate bar (150 grams).

This new tot is so small that it was born in early January but only recently spotted at the zoo. Invisible baby monkey!
The young pygmy marmoset's dad carries it around proudly, because in this species the fathers do most of the child rearing. The mother, Audrey, will feed the young one.

These marmosets live in forests in Brazil, Peru and Ecuador. While their population numbers seem reasonable at the moment, habitat destruction is a threat to them, as is being snatched up by the pet trade.

They are noisy small creatures, whistling and squealing in their native rainforests.

Because they are so small and live deep in rainforests, pygmy marmosets have not been well studied in the wild. Short-term field studies of them took place in the late 1960s and early 1970s; however, long-term studies only began in the mid-1970s by one researcher, Pekka Soini, according to the Primate Info Net.

When the young pygmy marmoset grows up, he will likely have elongated, sharp incisors and very sharp nails, which allow this type of monkey to eat a diet of gums and saps from trees.

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