Competitors take part in the 8th annual World Gravy Wrestling Championships at the Rose n Bowl Pub in Bacup, north west England on August 31, 2015. Contestants must participate in fancy dress and wrestle in a pool of Lancashire Gravy for 2 minutes whilst being scored for a variety of wrestling moves. (Photo by Oli Scarff/AFP Photo)

Photographer and animal lover Chris Keeney shows how to use a PetCam with your own pet and offers expert technical know-how and inspiring creative suggestions to get you started. This is Coulee, a border collie/golden retriver mix from Lethbridge, Alberta, Canada. (Photo by Chris Keeney/Princeton Architectural Press)

These stunning images show the 20-stone cat striking with lightning speed while the eight-foot reptile basks on a river island. The scene unfolded by the Cuiabá River in the Pantanal Wetlands of western Brazil. Photo: Jaguar attacks a Yacare Caiman. (Photo by Barcroft Media)

“Titanoboa is a genus of snake that lived approximately 58–60 million years ago, during the Paleocene epoch, a 10-million-year period immediately following the dinosaur extinction event. The only known species is the Titanoboa cerrejonensis, the largest snake ever discovered, which supplanted the previous record holder, Gigantophis”. – Wikipedia

Photo: Leah Del Rio views a replica of the prehistoric Titanoboa, the largest snake to ever live, on display at Grand Central Terminal on March 23, 2012 in New York City. (Photo by Michael Loccisano/Getty Images)

Floating on clear deep water and reflections near the cave entrance. Visitors can either bring their own kayaks or rent boats from the local community to paddle deep inside the cave and marvel at its wonders on March 2015 at Tham Khoun Ex, Laos. Tham Khoun Xe, commonly known as the Xe Bang Fai River Cave, in Laos, has over 15km of passages filled with awe-inspiring views and wide expanses of water. Photographer, John Spies, 59, captured scenes from the entrances of the huge underground river passages, intricate cave formations and views from a passage high above the water. The cave is formed by the Xe Bang Fai river, a major tributary of the Mekong and in the dry season can be traversed using inflatable kayaks. (Photo by John Spies/Barcroft Media/ABACAPress)

Surfers and others spend a day at Rockaway Beach as impact from Hurricane Lee delvers large surf and rip tides to much of the Northeast on September 14, 2023 in New York City. Hurricane Lee is predicted to make landfall from Nova Scotia to New Brunswick and also parts Maine this weekend. (Photo by Spencer Platt/Getty Images)

The National Geographic Photo Ark is a travelling exhibition of photographer Joel Sartore’s quest to create a photo archive of biodiversity around the world. So far, Sartore has captured studio portraits of more than 6,000 species – a number that he hopes to double. On 1 July, the ark will open at Melbourne zoo – the first time it has been exhibited in the southern hemisphere. More than 50 portraits will be on display, including many of Australian endangered animals being protected by programs at the zoo itself. These captions have been edited from text supplied by Melbourne zoo. Here: Barking owl. (Photo by Joel Sartore/National Geographic Photo Ark/The Guardian)

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)