A colony of penguins gather with the Bark Europa in the background, on March 05, 2015 in South Georgia Island. An adventurer has documented his 5,000 miles journey aboard a 100-year-old ship, sailing from Argentina to Antarctica to Cape Town. (Photo by Andrew Orr/Barcroft Images)

In this January 7, 2017 photo, Judeley Hans Debel squats down to remove a boot from Tic Tac, holding out his prosthetic leg after his therapeutic riding lesson at the Chateaublond Equestrian Center in Petion-Ville, Haiti. Anne-Rose Schoen, who founded the equestrian center, said perhaps the most important thing about therapeutic riding is it makes youngsters happy in a country where disabled people face enormous challenges. (Photo by Dieu Nalio Chery/AP Photo)

People in Mexico wave at U.S. Border Patrol agents on horseback patrolling the U.S.-Mexico border fence near San Diego, California, U.S., November 10, 2016. (Photo by Mike Blake/Reuters)

Using his camera skills, Marc meters the background sky in order to achieve the beautiful black silhouettes of the wildlife, Africa, 2010-2016. (Photo by Marc Mol/Barcroft Images)

A man gestures towards a bull during a traditional bullfighting festival called “Toros a la tica” in San Jose, Costa Rica January 6, 2017. (Photo by Juan Carlos Ulate/Reuters)

The two Pulis Quastie and Gin-Gin run in the snow in their garden in Lautertal, southern Germany, Thursday, January 5, 2017. (Photo by Michael Probst/AP Photo)

Six month- old baby elephant “Clear Sky” is kept afloat with the help of a harness during a hydrotherapy session at a local veterinary clinic in Chonburi Province on January 5, 2017. After losing part of her left foot in a snare in Thailand, baby elephant 'Clear Sky' is now learning to walk again – in water. (Photo by Roberto Schmidt/AFP Photo)

Nuninka, Bornean orangutan (Pongo pygmaeus), holds her newborn baby in the enclosure at Usti nad Labem Zoo, Usti nad Labem, Czech Republic January 3, 2017. (Photo by David W. Cerny/Reuters)