A brown bear waits for food at the zoo in Madrid, Spain on July 30, 2016. (Photo by Jorge Sanz/Pacific Press/SIPA Press/Rex Features/Shutterstock)

A young monk takes his food from the dining hall at Changangkha Lhakhang temple in Thimphu, Bhutan, April 13, 2016. (Photo by Cathal McNaughton/Reuters)

A trader sells mealies to commuter in Durban, South Africa, April19, 2016, as food prices continue to rise due to drought conditions. (Photo by Rogan Ward/Reuters)

A herd of wild monkeys ask for food from passing vehicles along a mountain road after a snowfall on October 20, 2020 in Luhuo County, Sichuan Province of China. (Photo by Jin Shujie/VCG via Getty Images)

A bee approaching the flowers of a willow in Otzberg, Germany on February 28, 2021. Willow catkins are a protected species and one of the first sources of food for insects in early spring. (Photo by Arne Dedert/DPA)

Over the years a large population of grey herons have made an unlikely home in urban Amsterdam. Julie Hrudova documents how the birds integrate into city life. Here: Hundreds of herons come to the city during winter to find food and shelter. (Photo by by Julie Hrudova/The Guardian)

In this November 18, 2014 photo, Murshida, 12, sits on the lap of her mother Marjina as the train leaves for their village in West Bengal, at a railway station in New Delhi, India. Six months ago, Marjina stepped off a train in New Delhi with her two children, hoping to find a better life after her husband abandoned them without so much as a goodbye. The family spent their days at a landfill picking through other people’s garbage to find salvageable bits to resell or recycle. After six months of poverty, illness and shame, they returned to that train station in New Delhi, headed back to an uncertain future to their hometown in West Bengal. (Photo by Altaf Qadri/AP Photo)

“Environmental Migrants: The Last Illusion” by photographer Alessandro Grassani, documents the life of people in Kenya, Mongolia and Bangladesh who migrate to escape environmental stresses to the city of their own countries in hopes for a better life. Here: Asia, Mongolia, March 27, 2011. A view of Ulaan Baator over the shoulder of a slumbering drunk. Alcoholism is a huge problem in the city, home to almost half of Mongolia's people. The capital's population has doubled in the past two years. High levels of unemployment and poverty await herders who abandon rural areas and arrive in the city, illiterate and untrained in any skills necessary for urban jobs. (Photo by Alessandro Grassani)