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)

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)

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)

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)

Andrew Profilli of Australia bleeds from the head during his 93kg bout against Priscus Fogagnolo of Australia during CFC 18 at Luna Park on August 26, 2011 in Sydney, Australia. (Photo by Ryan Pierse/Getty Images)

A reveller takes part in the battle of “Enfarinats”, a flour fight in celebration of the Els Enfarinats festival on December 28, 2015 in Ibi, Spain. Citizens of Ibi annually celebrate the festival with a battle using flour, eggs and firecrackers. (Photo by Pablo Blazquez Dominguez/Getty Images)

An Estonian competitor cheers during the “World Medieval Fighting Championship – the Israeli Challenge” in Rishon Letzion near Tel Aviv January 22, 2015. Israel hosted the tournament on Thursday, which includes 14 competitors from seven different countries – France, Belarus, Denmark, Estonia, Russia, Ukraine and Israel. (Photo by Amir Cohen/Reuters)