A member of the “Castellers Minyons de Terrassa” adjusts her belt before forming a human tower or ÒcastellÓ during the festival of the patron saint of Barcelona “The Virgin of Mercy” at Sant Jaume square in Barcelona, Spain, September 20, 2015. The formation of human towers is a tradition in Catalonia dating back to the 18th century. (Photo by Susana Vera/Reuters)

A heat-stressed koala waits as a resident pours water on its back on December 19, 2015 in Adelaide, Australia. Adelaide is experiencing an extreme heatwave, with temperatures reaching over 40 degrees for five consecutive days. (Photo by Morne de Klerk/Getty Images)

Kristen Wiig (2nd L) and Maddie Ziegler (2nd R) dance to Sia's “Chandelier” as the artist (R) stands with her back to the audience while performing at the 57th annual Grammy Awards in Los Angeles, California, February 8, 2015. (Photo by Lucy Nicholson/Reuters)

A mother bear takes a dip in the water to cool off in the warm summer sun but refuses to leave her three youngsters behind – so they climb aboard her back. (Photo by Jon Langeland/Solent News & Photo Agency)

Dhruva Aliman does a back somersault as he dismounts from a slackline on the beach at Santa Monica, California on October 19, 2014. Slackline is a balance sport where a line of webbing is adjusted at different levels of tension between two anchor points and participants (called slackers) perform tricks and stunts including somersaults. (Photo by Mark Ralston/AFP Photo)

Photographer Jim Zielinski from Florida, USA, captured this hilarious moment when a squirrel spied a tasty treat inside a novelty horse's head bird feeder in his back garden. (Photo by Jim Zielinski/Caters News)

Children try to push an injured and weak dolphin back into the water after it washed ashore during bad weather and high tide on a beach in Cilacap, Central Java, Indonesia August 12, 2016 in this photo taken by Antara Foto. (Photo by Idhad Zakaria/Reuters/Antara Foto)

A wax figure of President William Howard Taft is seated in the front seat with his detached head in the back after it was purchased from an auction of the Hall of Presidents Museum, which closed in November, in Gettysburg, Pennsylvania, U.S. January 14, 2017. (Photo by Mark Makela/Reuters)