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)

The fourth annual BigPicture Natural World Photography Competition aims to celebrate the diversity of life on Earth, and encourages people to protect and conserve it. Here: “The Salmon Catchers”. Terrestrial Wildlife. To capture this view of a mother grizzly bear and her cub, photographer Peter Mather set up a camera trap on a log that he knew the bears tended to traverse while fishing for salmon, in the Yukon River watershed in Canada. (Photo by Peter Mather/BigPicture Natural World Photography Competition 2017)

Brazil's Victoria Chamorro failed to stop the ball during their women's classification 7th-8th place water polo match against China at the 2016 Summer Olympics in Rio de Janeiro, Brazil, Friday, August 19, 2016. (Photo by Sergei Grits/AP Photo)

Kate O'Connor of Team Northern Ireland celebrates during the Women's Heptathlon High Jump on day five of the Birmingham 2022 Commonwealth Games at Alexander Stadium on August 02, 2022 in the Birmingham, England. (Photo by Matthew Lewis/Getty Images)

Marc Berthod of Switzerland during the Audi FIS Alpine Ski World Cup Men's Super Combined on February 12, 2012 in Sochi, Russia. (Photo by Vianney Thibaut/Agence Zoom/Getty Images)

Darryl Horner jnr riding Flying Agent (bottom R) races away to defeat Steven Pateman riding Bit of a Lad in Race 6, the 3yb Scotty Stewart Brierly Steeplechase, on Brierly Day during the Warrnambool Jumps Carnival at Warrnambool Racing Club on May 04, 2021 in Warrnambool, Australia. (Photo by Vince Caligiuri/Getty Images)

Laura Giombini of Italy reacts during the Women's Beach Volleyball preliminary round Pool D match against Jamie Lynn Broder and Kristina Valjas of Canada on Day 2 of the Rio 2016 Olympic Games at the Beach Volleyball Arena on August 7, 2016 in Rio de Janeiro, Brazil. (Photo by Shaun Botterill/Getty Images)

A member of team Japan performs during the women's team free final at the FINA World Championships in Budapest, Hungary on June 24, 2022. (Photo by Marton Monus/Reuters)