A man dressed as a “Trapajon”, representing entities of nature, poses for a picture after taking part in the Vijanera Festival in Silio, northern Spain, Sunday, Jan. 6, 2013. The Vijanera masquerade, of pre-Roman origin, is the first carnival of the year in Europe symbolizing the triumph of good over evil and involving the participation of crowds of residents wearing different masks, animal skins and brightly colored clothing with its own complex function and symbolism and becoming the living example of the survival of archaic cults to nature. (Photo by Daniel Ochoa de Olza/AP Photo)

Stunning images taken by Sean Lenz, 19, and Kristoffer Abligaard, 20, show picturesque waterfalls transformed into vibrant rainbows of colour. The awe-inspiring images were created by clever use of long exposure photography and glow sticks floating through water. Photo: Picturesque waterfalls transformed into rainbows of colour. (Photo by Sean Lenz/Kristoffer Abildgaard)

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)

An amazing artist transforms scrap metal into incredible sculptures of insects, birds, fish, and other animals. Edouard Martinet from Brittany, France, creates the sculptures from all manner of salvaged parts and junk, including car and bicycle parts, typewriters, and medical equipment. Photo: An ant by Edouard Martinet. (Photo by Edouard Martiniet/Caters News)

These zoo animals take on an altogether more sinister look after posing for a set of moody black and white portraits. Alex Teuscher has brought out the dark side in a range of exotic creatures with his artistic project which took two years to complete. Photo: White tiger. (Photo by Alex Teuscher/BNPS)

A mass pillow fight in Trafalgar Square in central London on April 5, 2014 on International Pillow Fight Day. (Photo by Jane Scanlan)

“If a man insisted always on being serious, and never allowed himself a bit of fun and relaxation, he would go mad or become unstable without knowing it”. – Herodotus. “You can discover more about a person in an hour of play than in a year of conversation”. – Plato. Photo: Mandalay, Burma. (Photo by Steve McCurry)

“Rivers Forgotten” is a journey through the passages and portals of the underground waterways that lie unseen below cities. Self-taught photographer Jeremy Kai brings these forgotten landscapes to light. Photo: Beneath the Toronto area, 2011. (Photo by Jeremy Kai)