Villagers from the Porto Novo community load into their canoes arapaima or pirarucu, the largest freshwater fish species in South America and one of the largest in the world, while fishing in Poco Fundo lake along a branch of the Solimoes river, one of the main tributaries of the Amazon, in the Mamiraua nature reserve near Fonte Boa about 600 km (373 miles) west of Manaus, November 26, 2013. Catching the arapaima, a fish that is sought after for its meat and is considered by biologists to be a living fossil, is only allowed once a year by Brazil's environmental protection agency. The minimum size allowed for a fisherman to keep an arapaima is 1.5 meters (4.9 feet). (Photo by Bruno Kelly/Reuters)

In this March 17, 2015 photo, Ashaninka Indian men, identified by locals as illegal loggers, tie tree trunks together to move them along the Putaya River near the hamlet of Saweto, Peru. Illegal logging persists unabated in this remote Amazon community where four indigenous leaders who resisted it were slain in September. The Putaya River is the waterway that transports felled trees, cut both legally and illegally, to the city of Pucallpa. (Photo by Martin Mejia/AP Photo)

Ants carry a leaf with a slogan reading “Merkel, Help!”, a reference of German Chancellor Angela Merkel, at the zoo in Cologne, Germany August 18, 2015. Some of the zoo's 500,000 leaf-cutting ants carry laser-cut leaves with slogans during a campaign to protect the Amazon rain forest, organised by the German branch of World Wild Fund for Nature (WWF) and Cologne Zoo. Picture taken through the glass of the display case. (Photo by Ina Fassbender/Reuters)

An Emperor Tamarin monkey, native to the Amazon rainforest, experiences its new home in the living rainforest enclosure at ZSL London Zoo on March 25, 2010 in London, England. Entitled “Rainforest Life” the large temperature and humidity controlled bio-dome is home to free-roaming monkeys, sloths, tree anteaters and tropical birds. The exhibit, which is opening in the International Year of Biodiversity, will be open to the public from March 27, 2010. (Photo by Oli Scarff/Getty Images)

In this January 27, 2019, photo, Hindu holy men of monastic order Juna Akhara participate in a ritual before becoming Naga Sadhus or naked holy men at Sangam, the confluence of three holy rivers during the Kumbh Mela or pitcher festival in Prayagraj Uttar Pradesh state, India. At every Kumbh, including this year's, thousands of devotees were initiated into the reclusive sect of the Naga Sadhus, naked, ash-smeared cannabis-smoking Hindu warriors and onetime-armed defenders of the faith who for centuries have lived as ascetics in jungles and caves. (Photo by Rajesh Kumar Singh/AP Photo)

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

Warriors from the Suri tribe in Ethiopia still stage the savage “Donga” battles – even after many fighters have been died from their injuries. Donga stick fights take place after the harvests, the Surmas count days owing to knots on a long stem of grass or jags on the trunk of a tree dedicated to that specific use. Here: A tribeswoman sporting a huge lip plate and wearing a skinned animal carcass on her head. (Photo by Eric Lafforgue/Exclusivepix Media)

Sikh devotee take part in Nagar Keertan procession on the occasion of Guru Gobind Singh birth anniversary in Allahabad, India on December 29, 2016. Guru Gobind Singh, born Gobind Rai (1666 – 1708), was the 10th Sikh Guru, a spiritual master, warrior, poet and philosopher. When his father, Guru Tegh Bahadur, was beheaded for refusing to convert to Islam, Guru Gobind Singh was formally installed as the leader of the Sikhs at age nine, becoming the last of the living Sikh Gurus. (Photo by Prabhat Kumar Verma/Pacific Press via ZUMA Wire/Rex Features/Shutterstock)