“Kilauea Rules”. The most extreme place we put ours kayakers to paddle till now. Photo location: Big Island, Hawaii. (Photo and caption by Alexandre Socci/National Geographic Photo Contest)

“Sperm whale opening it's huge mouth, Ogasawara Islands, Japan. Sperm whales are the biggest carnivorous animals on the planet. Each teeth in the mouth of adult specimen weights more than 1 kilogram. Interestingly enough that modern marine biologists believe that these teeth despite being fearsome play little role in capturing and eating giant squid – with their main function being mainly ritual aggression between males!”. (Photo by Alexander Safonov)

Chinese female weightlifter Xiang Yanmei, who competes in the 69 kg weightclass, rests with a weight on her stomach as she checks her phone during a training session in preparation for the Rio Olympics at the Training Center of General Administration of Sports in China on July 20, 2016 in Beijing, China. Xiang Yanmei won the World Championships in 2013 and 2015. (Photo by Kevin Frayer/Getty Images)

A woman carries a piglet as she runs on ice during a running challenge in Changsha, Hunan province February 8, 2015. A total of 20 people participated in the challenge requiring them to choose a pig ranging between 15 kg and 115 kg in weight, and carrying it while running on a 20.15-metre-long ice track. The participants that complete the challenge will be rewarded with the pig they carried, local media reported. (Photo by Darwin Zhou/Reuters)

In the remote Argentine Pampas you can find an incredible forest formed in the shape of a guitar. More than 35 years ago, Pedro Ureta unexpectedly lost his wife to a brain aneurysm. Devastated by the loss of his love, he decided to create a shrine to her memory in their field that could only be seen above-head from an airplane. Ureta chose a guitar because it was his late wife’s most loved instrument.

Stefan Dobrovolny of Austria and Inigo Munoz Elorza of Spain (R) stand in front of a quad bike during a simulated Mars mission on Tyrolean glaciers in Kaunertal, Austria, August 7, 2015. The Austrian Space Forum is sending some of its researchers to practice weight-less walking in spacesuits on a glacier which resembles the terrain on Mars. (Photo by Dominic Ebenbichler/Reuters)

A merino lamb attempts to jump out of its enclosure to find its mother shortly before feeding time at the Educational and Reserach Station for Animal Breeding (Lehr- und Versuchsanstalt fuer Tierzucht und Tierhaltung, or LVAT) in Brandenburg state on January 27, 2012 in Gross Kreutz, Germany. Hundreds of lambs have been born at the LVAT in recent weeks in the midst of the station's lambing season. Many of the lambs will be sold just before Easter, when they will have grown to a weight of over 40kg, as lamb is the traditional German Easter meal. (Photo by Sean Gallup/Getty Images)

A woman mourns the loss of her husband, next to a placard which reads “I'm a pusher”, who was shot dead by an unidentified gunman in Manila on July 23, 2016. Philippine President Rodrigo Duterte swept to power in May on a promise to clampdown on drugs, and police have since confirmed killing nearly 200 people in a two-month crime blitz. There has also been a surge in killings by anti-drug vigilantes who leave victims' corpses on city streets wrapped in packaging tape with signs accusing them of being drug dealers. (Photo by Noel Celis/AFP Photo)