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 spotted owlet appears to be playing peek-a-boo near Rancharda Lake in Ahmedabad, India on February 9, 2016. The species is common across the Indian subcontinent. (Photo by Caters News Agency)

A member of the United Arab Emirates armed forces gestures as the first batch of UAE military personnel returns from Yemen in Abu Dhabi, November 7, 2015. (Photo by Reuters/United Arab Emirates News Agency WAM)

A black bear cub performs for its mum at the Pocosin Lakes National Wildlife park in North Carolina, US in January 2022. (Photo by Jennifer Hadley/Animal News Agency)

A lion cub wakes in the morning sun at the Zimanga private game reserve in South Africa on April 9, 2022. (Photo by Calvin Kotze/Animal News Agency)

A girl carries sorghum stalks during the sorghum harvest season in Amran province, Yemen, October 24, 2020. (Photo by Xinhua News Agency/Rex Features/Shutterstock)

Aerial photo taken on June 19, 2021 shows the scenery of Mount Huashan in northwest China's Shaanxi Province. (Photo by Xinhua News Agency/Rex Features/Shutterstock)

A black gibbon is seen in a cage before being released into the wild by Indonesian nature conservation agency (BKSDA) in Jantho forest, Aceh province on August 26, 2021. (Photo by Chaideer Mahyuddin/AFP Photo)