World's Smallest Monkey Gives Birth to Twins That Weigh Just Half an Ounce Each

The world’s smallest monkey has welcomed tiny twins into the world at England's Chester Zoo.

Audrey, a pygmy marmoset, gave birth to the monkeys on July 25, but they have only now grown to the size where you can spot them in their zoo habitat.

At present, the tiny animals weigh only 15 grams — or .53 ounces — each.

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“Pygmy marmosets actually have relatively large babies for their tiny size. An adult will only weigh up to around 150 grams and so each baby equates to around 10 percent of its body weight,” said Dr. Nick Davis, the zoo's deputy curator of mammals.

The twins’ dad, Gumi, is taking on most of the parental chores while Audrey gives the babies their regular feedings like all other eastern pygmy marmosets.

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“The youngsters can therefore often be seen being carried by dad Gumi for long periods of time as mum takes a well-deserved break,” David said.

Eastern pygmy marmosets are native to the rainforests of western Brazil, southeastern Colombia, eastern Ecuador and eastern Peru, where they are threatened by both habitat loss and the pet trade.

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