The photographs feature fish that have been specially treated to make the stained skeletal tissues visible through the skin and flesh. The technique, developed by Dr. Adam Summers, uses dyes, hydrogen peroxide, a digestive enzyme and glycerin to make the flesh seem to disappear. Photo: This image of the butterfly ray (Gymnura crebripunctata) helped scientists study the joints in its wings. (Photo by Adam Summers)

Look at the image for long enough and you can make the train change direction simply by thinking about it. Freaky.

Climate change activists dressed up as black birds protest in St. Ives, on the sidelines of the G7 summit in Cornwall, Britain, June 11, 2021. (Photo by Dylan Martinez/Reuters)

The Invasion. A quiet street in Macau. Modernization around is quickly changing the city, as documented by Paul Tsui. (Photo by Paul Tsui/National Geographic Travel Photographer of the Year Contest)

A robin perches on a spade handle in a garden on a rainy day in Lixwm, north Wales. Researchers said this week that when European robins are subjected to human-produced noise, their behaviour changes. (Photo by DGDImages/Alamy Live News)

Indigenous dancers participate in a traditional healing ceremony for the mother earth at El Salvador del Mundo Square in San Salvador, December 10, 2014. Salvadorean indigenous organizations participated in a ceremony to ask for solutions to stop climate change and respect planet earth as the U.N. Climate Change Conference COP 20 is bring held in Peru. The two-week long United Nations climate summit opened on December 1 in Lima, with experts and analysts from around the world gathering to discuss melting glaciers and extreme weather patterns. (Photo by Jose Cabezas/Reuters)

Aymara indigenous people celebrate the “Roscasiri”, the change of command of local authorities, in Pomata District, one of seven districts of the Chucuito Province in the Puno Region, southern Peru, on January 1, 2022. This ancient Aymara event, in which people adorn themselves with breads and fruits that represent abundance for the new year, celebrates the change of command of local authorities. (Photo by Carlos Mamani/AFP Photo)

A woman reacts to having leaves thrown on her, while taking a photo, in Central Park as leaves begin to change colors on October 26, 2022 in New York City. Leaves around parts of Central Park have begun changing colors while much of Long Island and Upstate New York have already peaked. (Photo by Alexi Rosenfeld/Getty Images)