A photographer tested the concentration of several pairs of dogs as he captured their reactions to treat time in a series of shots. Christian Vieler, 47, of Waltrop, Germany, has been a professional dog photographer since 2016. He came up with the idea of snapping two dogs catching treats simultaneously. Here: Basset Hounds. (Photo by Vieler Photography/Caters News Agency)

Female members of the Chinese People's Liberation Army (PLA) honour guard stand behind a string to ensure that they are in a straight line before a welcoming ceremony for Russian President Vladimir Putin outside the Great Hall of the People in Beijing, China, June 25, 2016. (Photo by Kim Kyung-Hoon/Reuters)

Participants perform a dragon dance as they march during a lantern parade marking the start of a month- long “Lotus Lantern Festival” to celebrate the upcoming Buddha' s birthday, in Seoul on April 29, 2017 Buddha' s birthday falls on May 3. (Photo by Ed Jones/AFP Photo)

Revelers participate in J'Ouvert, an overnight celebration the night before the West Indies Day Parade in Brooklyn, NY on September 3, 2018. Violence in past years led NYPD to shut down the parade route until 2am. (Photo by Stephen Yang)

A string is used to ensure that the skirts of female members of the honour guard are in the same height from the ground as they prepare for a welcoming ceremony for Congo Republic President Denis Sassou Nguesso outside the Great Hall of the People in Beijing, China, July 5, 2016. (Photo by Jason Lee/Reuters)

Hindu priests wash the head of a buffalo calf which was sacrificed as part of a ritual at a temple during the Durga Puja festival in Agartala, India, October 10, 2016. (Photo by Jayanta Dey/Reuters)

American model Bella Hadid poses as she arrives for the screening of the film “Tre Piani” (Three Floors) at the 74th edition of the Cannes Film Festival in Cannes, southern France, on July 11, 2021. (Photo by Reinhard Krause/Reuters)

Gold medalist Jesper Pedersen of Norway with silver medalist Rene de Silvestro of Italy and bronze medalist Liang Zilu of China are seen during the flower ceremony for the Para Alpine Skiing, Men's Giant Slalom Sitting on March 10, 2022. (Photo by Aly Song/Reuters)