A Thai veterinarian sterilizes a monkey in a bid to control the birth rate of the monkey population in Hua Hin city, Prachuap Khiri Khan Province, Thailand, 15 July 2017. (Photo by Narong Sangnak/EPA/EFE)

The pygmy marmoset (Cebuella pygmaea) is a small New World monkey native to rainforests of the western Amazon Basin in South America. It is notable for being the smallest monkey in the world at just over 100 grams (3.5 oz). It is generally found in evergreen and river edge forests and is a gum-feeding specialist

Greetings, sickly monkeys! Planet Nibiru is near already. Confess, parasites! Love you! Yours truly, Avax

A wild monkey has stunned animal lovers after it adopted an abandoned kitten and cared for it as his own. The young long-tailed macaque monkey was spotted in a forest protectively nuzzling and grooming the ginger kitten, making sure no harm came to it.

Ucil, a trained monkey, takes part in a street performance on June 1, 2011 in Jakarta, Indonesia. The street performances usually involve the monkeys wearing masks, such as dolls' heads or attire to mimic humans, with the monkeys trained to act out human activities such as shopping, riding bicycles or other simulations of human behaviour. Poverty drives the handlers to exploit the monkeys in the hope of earning small change, but the effect and cruelty to the monkeys is a cause that charities such as the Jakarta Animal Aid Network are increasingly taking up. (Photo by Ulet Ifansasti/Getty Images)

A Thai wildlife department official carries a long-tailed macaque to a cage at a village in Bangkok, Thailand, September 21, 2015. Thai authorities were relocating the long-tailed macaques on Monday to lessen conflicts with the local community. (Photo by Chaiwat Subprasom/Reuters)

A 20-year-old Japanese macaque monkey named Monday scratches her eyes while suffering an allergy to pollen from the cedar tree at Awajishima Monkey Centre on March 17, 2013 in Sumoto, Japan. Many monkeys are suffering the effects of hay fever at this time of the year, with the typical symptoms being the same as with humans. According to Awajishima Monkey center this year hay fever is higher than last year, the pollen season is from February to April. (Photo by Buddhika Weerasinghe)

A long-tailed macaque grabs a necklace from a statue during the annual Monkey Buffet Festival at the Pra Prang Sam Yot temple in Lopburi, north of Bangkok November 30, 2014. The festival provides food and drinks to the local monkey population, which numbers more than 2,000, to thank them for drawing tourists to the town. (Photo by Damir Sagolj/Reuters)