Couples take part in the “Love and Challenge Marathon” in Hanoi, Vietnam, 16 August 2015. Fifty couples, who are going to get married, participated in the event which is held the fifth time. This year, the winners of the marathon received a honeymoon trip to Malaysia. (Photo by Luong Thai Linh/EPA)

A picture made available 27 November 2015 shows a handler putting his head between the gaping fangs of a crocodile during a show at the Samutprakarn Crocodile Farm and Zoo, Samutprakarn province, outside Bangkok, Thailand, 26 November 2015. The farm and zoo claims to be the world's largest crocodile farm with more than 80,000 freshwater and marine crocodiles, and offers shows such as crocodile wrestling to attract tourists. (Photo by Diego Azubel/EPA)

“Fly cap for a vine snake”. A fly lands on the head of a vine snake in the Choco of Colombia. (Photo and caption by Robin Moore/National Geographic Traveler Photo Contest)

ATTENTION! All pictures are presented in high resolution. To see Hi-Res images – just TWICE click on any picture. In other words, click small picture – opens the BIG picture. Click BIG picture – opens VERY BIG picture.

“Red Land: Sunset Cloud Village is one of the most picturesque places in Red Land, China. As its name indicates, it's best to see before sunset. The reddish brown soil turns redder after rainfall and after farmers plow the land”. (Photo and comment by Peng Jiang/National Geographic Photo Contest via The Atlantic)

Kyrgyz men on horseback compete during their traditional game of “Oodarysh” during the celebrations of the 90th anniversary formation of the Chui region in the village of Kuntu some 20 kms from Bishkek on May 27, 2016. (Photo by Vyacheslav Oseledko/AFP Photo)

A racegoers walks into a rubbish bin following 2016 Melbourne Cup Day at Flemington Racecourse on November 1, 2016 in Melbourne, Australia. (Photo by Scott Barbour/Getty Images)

Schoolchildren look at a lifelike animatronics display of a dinosaur at the dinosaur-themed Zoo-rassic Park in Singapore on November 16, 2016. To raise awareness on the sixth mass extinction, the Singapore Zoo and River Safari displayed lifelike dinosaur animatronics where visitors can trail along the Dinosaur Valley which does not involve living animals. (Photo by Roslan Rahman/AFP Photo)

An urban fox walks alongside the Mall in central London, Britain, November 29, 2016. (Photo by Toby Melville/Reuters)