A wrestler from the Nuba Mountains tribe is seen during a celebration of their cultural heritage, as part of ongoing events to commemorate the International Day of the World's Indigenous Peoples, in Omdurman August 15, 2015. The International Day of the World's Indigenous Peoples is observed on August 9 annually. (Photo by Mohamed Nureldin Abdallah/Reuters)

A Dongria tribe girl holds her traditional weapon and dance on the last day of their two days long Niyamraja Festival atop of the Niyamgiri hills near Lanjigarh in Kalahandi district, Orissa state. (Photo by Biswaranjan Rout/AP Photo)

Some people prepare to catch offerings thrown by Tengger tribe people into the crater of Bromo volcano to in Probolinggo, East Java province, on June 30, 2018, as part of Yadnya Kasada festival which falls on the 14th day of the Kasada month based on the traditional Hindu lunar calendar. (Photo by Juni Kriswanto/AFP Photo)

For more than 2,000 years, women from the Baiga tribe in the highland district of Dindori, in central India’s Madhya Pradesh state, have been tattooed. Sumintra, 25, from Bona village, has the markings across her forehead, legs and arms. The women who work as tattoo artists are knowledgable about the different types of designs and pigments preferred by various tribes, and their meanings are passed to them by their mothers. The tattooing ‘season’ begins with the approach of winter. (Photo by Ronny Sen/WaterAid/The Guardian)

A man from Dinka tribe holds his AK-47 rifle in front of cows in a Dinka cattle herders camp near Rumbek, capital of the Lakes State in central South Sudan December 14, 2013. (Photo by Goran Tomasevic/Reuters)

A devotee offers oil lamps on top of his body as part of a ritual during Dashain, the biggest religious festival for Hindus in Bhaktapur, Nepal, October 22, 2015. Hindus in Nepal celebrate victory over evil during the festival by flying kites, feasting, playing swings, sacrificing animals and worshipping the Goddess Durga as well as other gods and goddess as part of celebrations held throughout the country. (Photo by Navesh Chitrakar/Reuters)

A medium performs the religious dance "Narsingh Avatar" during the traditional Kartik dance festival at Patan Durbar Square in Lalitpur, Nepal November 24, 2015. Observed for eight days, the festival is the longest dance festival in Nepal, and features a mix of drama, music and dialogues introduced by King Siddhinarsingh Malla in 1637 AD. (Photo by Navesh Chitrakar/Reuters)

People look at revellers (L) waiting to take part in a LGBT (lesbian, gay, bisexual and transgender) pride parade to mark Gaijatra Festival, also known as the festival of cows, in Kathmandu, Nepal, August 30, 2015. Hundreds of lesbians, gays, bisexuals and transvestites paraded through Nepal's capital Sunday to demand that rights for sexual minorities be included in the country's new constitution that is being finalized. (Photo by Navesh Chitrakar/Reuters)