Wedges of an orange generate enough current and electrical juice – 3.5 volts – to power an LED. The fruit’s citric acid helps electrons flow from galvanized nails to copper wire in this 14-hour exposure. This image was published in September’s Visions of Earth, a trio of photos that appear in each issue of National Geographic. (Photo by Caleb Charland/National Geographic)

A child travels in a pickup truck next to a coffin in Les Cayes, Haiti, Monday, August 16, 2021. Haitians are searching for survivors and the dead in collapsed buildings following the powerful earthquake over the weekend as hospitals overflow with patients, and Tropical Depression Grace is predicted to reach Haiti Monday night. (Photo by Joseph Odelyn/AP Photo)

Since Rodrigo Duterte became president last year, his brutal campaign against drugs has claimed thousands of lives. Human rights groups say he is guilty of crimes against humanity, yet that is scant comfort to those mourning loved ones. Here: Constantino de Juan’s seven children sit on a sofa that still bears the bullet hole from their father’s shooting. Juan was preparing a spaghetti dinner on his daughter’s birthday when he was killed. (Photo by James Whitlow Delano/Funded by the Pulitzer Center on Crisis Reporting/The Guardian)

Maasai men of Matapato jostle to parade as they attend the Olng'esherr (meat-eating) passage ceremony to unite two age-sets; the older Ilpaamu and the younger Ilaitete into senior elderhood as the final rite of passage, in Maparasha hills of Kajiado, Kenya on September 23, 2020. Thousands of Maasai men clad in red and purple shawls and with their heads coated in red ochre gathered this week for a ceremony that transforms them from Moran (warriors) to Mzee (elders). (Photo by Thomas Mukoya/Reuters)

A red squirrel sniffs out nuts inside Christmas stockings as part of the festive celebrations and enrichment programme at Wildwood Escot Park in Ottery St Mary, Devon, United Kingdom on December 17, 2020. (Photo by Ben Birchall/PA Images via Getty Images)

A reveller drinks wine while waiting for the launch of the “Chupinazo” rocket, to mark the official opening of the 2023 San Fermín fiestas in Pamplona, Spain, Thursday, July 6, 2023. (Photo by Alvaro Barrientos/AP Photo)

The secretive indri (Indri indri) of Madagascar, the largest living lemur. It is also critically endangered and highly evolutionarily distinct with no close relatives, which makes its branch one of most precarious on the mammal evolutionary tree. In the likely event that the indri goes extinct, we will lose 19m years of unique evolutionary history from the mammal tree of life. (Photo by Pierre-Yves Babelon/Aarhus University)

A visitor jumps for a photograph on the world's highest and longest glass-bottomed bridge above a valley in Zhangjiajie in China's Hunan Province on August 21, 2016. The bridge, which opened to the public on a trial basis on Saturday, spans 430 meters (1,410 feet) and rises about 300 meters (984 feet) above a valley in a scenic zone, making it the world's highest and longest glass-bottomed bridge according to Chinese state media. (Photo by Fred Dufour/AFP Photo)