National Geographic has created “Air, Land & Sea: the 50 greatest wildlife photographs” exhibition. Here: CT4 Crocodile cave on the Salamat river. Set up with Nathan Williamson last chip rain came while we were with the nomads. (Photo by Michael Nichols/National Geographic)

A person dressed up as Saitama from One Punch Man attends the 2018 New York Comic Con in Manhattan, New York on October 4, 2018. (Photo by Shannon Stapleton/Reuters)

Actors Justin Timberlake (L) and Mila Kunis present an award onstage during the 2011 MTV Movie Awards at Universal Studios' Gibson Amphitheatre on June 5, 2011 in Universal City, California. (Photo by Kevin Winter/Getty Images)

The report, prepared by the Sustainable Development Solutions Network (SDSN) and the Earth Institute at Columbia University, showed Syria, Afghanistan and eight sub-Saharan countries as the 10 least happy places on earth to live. The top 10 this year were Denmark, Switzerland, Iceland, Norway, Finland, Canada, Netherlands, New Zealand, Australia, and Sweden. Denmark was in third place last year, behind Switzerland and Iceland. The bottom 10 were Madagascar, Tanzania, Liberia, Guinea, Rwanda, Benin, Afghanistan, Togo, Syria and Burundi. The United States came in at 13, the United Kingdom at 23, France at 32, and Italy at 50. Here: #8. NEW ZEALAND: A woman dives from a platform into a giant air bed at a park in Palmerston North September 29, 2011. (Photo by Marcos Brindicci/Reuters)

A dog jumps into a swimming pool to retrieve a ball during the Chatsworth House Country Fair near Edensor, Britain on August 31, 2018. (Photo by Darren Staples/Reuters)

Selena Gomez, left, and Taylor Swift arrive at the 58th annual Grammy Awards at the Staples Center on Monday, February 15, 2016, in Los Angeles. (Photo by Jordan Strauss/Invision/AP Photo)

A model walks the runway at the Luca Luca Spring 2012 fashion show during Mercedes-Benz Fashion Week at The Stage at Lincoln Center on September 9, 2011 in New York City. (Photo by Frazer Harrison/Getty Images for Mercedes-Benz Fashion Week)

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)