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)

Two Corgi dogs collide as they cross the finish line during the SoCal “Corgi Nationals” championship at the Santa Anita Horse Racetrack in Arcadia, California on May 27, 2018. The event saw hundreds of Corgi dogs compete for the fastest dog title at the 17 race event. (Photo by Mark Ralston/AFP Photo)

These adorable pawtraits seem to show the personalities of a variety of canines, capturing their incredible diverseness in their expressions and fine details. Khokhlov and Ershova, who are from Moscow, have taken portraits of about 50 breeds of pooches – earning much critical acclaim. (Photo by Alexander Khokhlov/Veronica Ershova/Caters News Agency)

Afghan dogs fight during the weekly dog fight in Kabul, Afghanistan, 17 February 2017. Under the Taliban dog fighting was forbidden, but since their fall it has become a major source of entertainment for hundreds of Afghans, where bets can amount to thousands of dollars and the dogs, which must be over one year old, are well-cared for by their owners and fed milk, butter and meat. (Photo by Hedayatullah Amid/EPA)

Prince Dudeman stands on Ryan Thor's head at the 14th annual Helen Woodward Animal Center “Surf-A-Thon” where more than 70 dogs competed in five different weight classes for “Top Surf Dog 2019” in Del Mar, California, U.S., September 8, 2019. (Photo by Mike Blake/Reuters)

A dog wearing a Captain America costume, walks on a leash at the “Blocao” dog carnival parade in Rio de Janeiro, Brazil, Saturday, February 18, 2023. (Photo by Silvia Izquierdo/AP Photo)

Cosplayers wearing face masks pose for a picture at the China Digital Entertainment Expo and Conference (ChinaJoy) in Shanghai, following the coronavirus disease (COVID-19) outbreak, China on July 31, 2020. (Photo by Aly Song/Reuters)

An artists performs on the street during a Myfest festival marking the May Day in the Kreuzberg district in Berlin, Germany on May 1, 2018. (Photo by Fabrizio Bensch/Reuters)