Mr. Zhong Hua, of Johns Hopkins University School of Medicine, took this image of the peripheral nerves (those outside of the brain) in an 11.5-day-old mouse embryo, magnified five times. (Photo by Zhong Hua)

People play on a beach along the Arabian Sea on a hot summer day in Mumbai, India, April 29, 2016. (Photo by Danish Siddiqui/Reuters)

Bathing suit models are shown listening to the radio on the beach, circa 1940's. (Photo by Bettmann Archive/Getty Images)

Models present creations from the SGM ART MOUSE JI during the China Fashion Week in Beijing, China, 25 October 2020. The fashion​ event runs from 24 October to 01 November. (Photo by Wu Hong/EPA/EFE)

Indian men sleep in the shadow of an overflowing cloth container of hay, to be used as animal fodder, on a truck on a hot summer day in Ajmer in the western state of Rajasthan on May 30, 2018. (Photo by Shaukat Ahmed/AFP Photo)

Aerial view over mud and waste from the disaster caused by dam spill in Brumadinho, Minas Gerais, Brazil, 26 January 2019. At least nine people have died and 300 are missing after a tailings dam burst at the Feijao mine in southeastern Brazil owned by Vale, the world's largest iron-ore producer, the Minas Gerais state government said. The dam in Brumadinho near Belo Horizonte broke on 25 January at around mid-day, unleashing a river of sludge that destroyed some nearby houses. (Photo by Antonio Lacerda/EPA/EFE)

Finding just the right spot above the clouds at Camp 1 on Ama Dablam, Danuru Sherpa uses his iPhone to catch up with friends and family. Even at 18,500 feet (5,654 meters), climbers here can check their email and other dispatches from the world below. (Photo by Aaron Huey/National Geographic)