Leo, an orphaned Sumatran orangutan, is taken to the Sumatran Orangutan Conservation Programme rehabilitation centre. Leo will join other orangutans who have been reintroduced to the Pinus Jantho nature reserve. The SOCP has gradually formed a completely new wild population of species that have been threatened with extinction. (Photo by Sutanta Aditya/Barcroft Images)

A picture taken on October 5, 2018, shows a general view of Migingo island which is densely populated by residents fishing mainly for Nile perch in Lake Victoria, the continent's largest lake, on the border of Uganda and Kenya. More than 500 people live on the island, which is barely 2,000-square-metres. (Photo by Yasuyoshi Chiba/AFP Photo)

Gers, traditional Mongolian tents, are seen on a hill in an area known as a ger district in Ulan Bator June 26, 2013. Approximately 60 percent of the population of Ulan Bator live in settlements known as ger districts and in many cases residents have limited access to basic services such as water and sanitation. According to a 2010 National Population Center census, every year between thirty and forty thousand people migrate from the countryside to the capital Ulan Bator. Ger districts in the city have been expanding rapidly in recent years. Mongolia is the world's least densely populated country, with 2.8 million people spread across an area around three times the size of France. (Photo by Carlos Barria/Reuters)

China has recently relaxed its one child policy that was used to control a burgeoning population. A couple has their wedding photo taken in an old quarter of Beijing on May 24, 2016. (Photo by Michael Robinson Chavez/The Washington Post)

Sri Lankan participants control their bulls during a traditional cart race to mark the Sri Lanka National New Year in Homagama near Colombo on April 23, 2017. The new year marked by both the majority Sinhalese and minority Tamil population fell on April 14. (Photo by Lakruwan Wanniarachchi/AFP Photo)

Nigerians take a photo in their traditional clothes during Eid al-Fitr prayers in Lagos, Nigeria on May 2, 2022. Muslims gather to perform Eid al-Fitr prayers held in Nigeria, the country with the largest Muslim population in Africa. (Photo by Adeyinka Yusuf/Anadolu Agency via Getty Images)

An Ezo red fox, or kitakitsune, and her cub are seen at night near the city of Sapporo, northern Japan, 15 May 2022. Authorities are calling population to avoid contact with the animals due to risks of echinococcosis infection. (Photo by JIJI Press/EPA/EFE)

A macaque crosses a pedestrian overpass in Hong Kong, China, 08 November 2021. According the Agriculture, Fisheries and Conservation Department, AFCD, the total population of wild monkeys in Hong Kong is about 1,800, distributed in 30 social troops. (Photo by Jerome Favre/EPA/EFE)