These powerful images capture the spear-wielding tribes of Papua new Guinea who believe they are possessed with the spirit of the crocodile. They show how the Kangunaman clansmen scar their backs to resemble reptile scales while the Huli Wigmen wear elaborate headdresses to signal they are ready for battle. (Photo by Trevor Cole/Media Drum World)

Will Rosner and a playful humpback whale pose for a selfie. This man is certainly knows how to enjoy life travelling the South Pacific and posing for selfies with a whale. Australian carpenter Will Rosner, 24, from Sydney, Australia, has been travelling the world for the past 18 months but nothing could have prepared him for this incredible postcard moment. Swimming in the pristine waters of the Tonga in the Pacific Ocean Will was lucky enough to have the chance to swim with an entire pod of humpback whales. (Photo by WIll Rosner/Caters News)

Students of the "Escola de Papai Noel do Brasil" (Brazil's school of Santa Claus) travel on a ferry through Guanabara bay, during their graduation ceremony in Rio de Janeiro, Brazil, November 10, 2015. The school holds 4 days' lessons in Santa-training, teaching Christmas carols, how to interact with children, and also how to wear the heavy red suit in Rio's typical 104-degree (40 degrees celsius) summer weather that is common around the holidays. (Photo by Pilar Olivares/Reuters)

In this Tuesday, March 12, 2019 photo, a visitor takes part in an immersive experience showing visitors how dogs see from inside the head of a dog at the California Science Center in Los Angeles. A new exhibit at a Los Angeles museum examines the relationship between dogs and humans and explores why the two species seem to think so much alike and get along so well. “Dogs! A Science Tail” opens Saturday, March 16, 2019, at the California Science Center. (Photo by Richard Vogel/AP Photo)

Soap Bubble Structures by Kym Cox. Bubbles optimise space and minimise their surface area for a given volume of air. This phenomenon makes them a useful tool in many areas of research, in particular, materials science and “packing” – how things fit together. Bubble walls drain under gravity, thin at the top, thick at the bottom, which interferes with travelling lightwaves to create bands of colour. Black spots show the wall is too thin for interference colours, indicating the bubble is about to burst. (Photo by Kym Cox/2019 Science Photographer of the Year/RPS)

It is simply staggering how complicated some items really are. We never think about it, but some items that we use every day consist of hundreds of parts meticulously put together and working perfectly. Todd McLellan is a photographer who based his newest book “Things Come Apart” on the complexity of various old and new tech. By carefully taking apart various items and arranging all of the parts in perfect order, Todd has allowed us not only to look inside various appliances, but also to appreciate the astounding complexity of these items. Just like the human mind, we are so used to seeing and talking with people that we forget just how complicated their minds really are. It would be great if we could “take apart” the human mind in order to gain some insight into the person’s thoughts and desires. However, very few people are capable of doing it, while the rest will remain blind to the obvious. (Photo by Todd McLellan)

Vanessa Silva, 38, feeds macaws that fly to her apartment window every day looking for food, in Caracas, Venezuela, on November 24, 2014. A group of gold-and-royal blue birds poked their heads through Silva’s window, as if saying “I’m here, is anyone home?” “I’d seen them flying when I was down on the street, and I thought ‘Oh how pretty,’” the 38-year-old said, a macaw eating out of her hand. (Photo by Ariana Cubillos/AP Photo)

Coloured X-ray of a barn owl. A physicist has used X-ray to create an extraordinary collection of artwork. Arie van't Riets pictures reveal birds, fish, monkeys and flowers in an incredible new light. The 66-year-old, from Bathmen in the Netherlands, began X-raying flowers as a means to teach radiographers and physicians how the machine worked. But after adding a bit of colour to the pictures, the retired medical physicist realised the potential for an exciting new collection of art. (Photo by Arie van't Riet/Barcroft Media)