Horse racing is part of Naadam, a festival organized every July in Mongolia to celebrate the People’s Revolution. Using children as jockeys in such races has a centuries-long tradition. Boys and girls as young as 5 (although the law imposes a minimum age limit of 7) ride in races that can be dangerous, with hundreds of horses running across the steppe at distances of 12 to 28 kilometres at great speeds. (Photo by Tomasz Gudzowaty)

A demonstrator wears a message on a t-shirt in Tahrir Square on May 27, 2011 in Cairo, Egypt. The ruling Supreme Council of the Armed Forces said that there would be no use of violence against protests dubbed “the Second Revolution of Anger” taking place in Cairo and other cities in Egypt. (Photo by Peter Macdiarmid/Getty Images)

A mosaic artwork, copied from an original painting, is pictured in a workshop in Kafranbel town in the Idlib governorate January 17, 2015. The mosaic workshop with 30 workers, manufactures artistic and revolutionary mosaics in Kafranbel. Each mosaic artwork takes 5 to 10 days to complete. The artists exhibit their artwork in local and international exhibitions, and have a scheduled exhibition this month about the “Syrian Revolution” in Turkey. (Photo by Khalil Ashawi/Reuters)

Sustainable development goal target 12.5 is to reduce waste. But with a planet increasingly dependent on technology, is that even possible? As of today, over 30m tonnes of electronic waste has been thrown out so far this year, according to the World Counts. Most e-waste is sent to landfills in Asia and Africa where it is recycled by hand, exposing the people who do it to environmental hazards. Kai Loeffelbein’s photographs of e-waste recycling in Guiyu, southern China show what happens to discarded computers. (Photo by Kai Loeffelbein/laif Agentur)

In this photo taken Wednesday, December 5, 2018, a woman who scavenges recyclable materials from garbage for a living is seen through a cloud of smoke from burning trash, surrounded by Marabou storks who feed on the garbage, at the dump in the Dandora slum of Nairobi, Kenya. As the world meets again to tackle the growing threat of climate change, how the continent tackles the growing solid waste produced by its more than 1.2 billion residents, many of them eager consumers in growing economies, is a major question in the fight against climate change. (Photo by Ben Curtis/AP Photo)

Sеx worker Geraldine wearing cat make-up sits on her usual corner as she waits for clients outside the Revolution subway station, in Mexico City, Saturday, March 13, 2021. Geraldine, 30, a sеx worker since age 15, says many of her regular clients have stopped coming amid the coronavirus pandemic and that seeing new clients presents new health and security risks. She is most concerned about the risk of bringing COVID-19 home to her partner, who has diabetes. (Photo by Rebecca Blackwell/AP Photo)

A Puffing Billy steam train hauled by locomotive 14A crosses the Monbulk Creek trestle after leaving Belgrave station near Melbourne, October 20, 2014. While the discovery of steam power 200 years ago powered the Industrial Revolution, the world long ago shunted most steam trains onto the sidings of history. (Photo by Jason Reed/Reuters)