An army dog stands up as retiring soldiers salute their guard post before retirement in Suqian, Jiangsu province, China on November 29, 2017. (Photo by Reuters/China Stringer Network)

In this Wednesday, January 3, 2018 photo, yoga instructor Danuta Wolk-Laniewski, demonstrates goat yoga at the Aussakita Acres farm in Manchester, Conn. The farm is partnering with the Hartford Yard Goats, the Double-A affiliate of the Colorado Rockies baseball team, to offer goat yoga at Dunkin Donuts Park, the team's $71 million stadium in Hartford. (Photo by Pat Eaton-Robb/AP Photo)

A German special anti-tank gun is ready to fire during the army maneuvers in Silesia, Poland, on September 22, 1928. (Photo by AP Photo)

An Orchid Mantis (Hymenopus coronatus) is perched on the head of a frog hanging from a tree branch on March 15, 2017 in Padang, Indonesia. (Photo by Riau Images/Barcroft Images)

A woman carries earthen pots to fill them with drinking water on a hot summer day, on the outskirts of Ajmer, Rajasthan, India April 25, 2017. (Photo by Himanshu Sharma/Reuters)

People enjoying the races on a wet day at Chester Racecourse on May 12, 2017 in Chester, England. (Photo by Alan Crowhurst/Getty Images)

Nutrias venture near the camera at the river Nidda in Frankfurt am Main, Germany, 15 June 2017. The rabbit sized animals are often confused with biebers by amateurs. (Photo by Boris Roessler/DPA)

A herd of elephants cross a road that passes through the flooded Kaziranga National Park in the northeastern state of Assam, India, July 12, 2017. (Photo by Anuwar Hazarika/Reuters)