Antek Marciniec holds onto a slackline after falling off as he highlines between two cliffs at Diamond Bay on December 21, 2014 in Sydney, Australia. Slacklining is a balance sport in which participants walk on a flat nylon webbing anchored between two points with the tension adjusted to allow for slack, providing an experience similiar to that of walking on a trapmoline. Highlining is a style of slacklining where the two anchor points are set up with significant elevation from the ground or water. (Photo by Cameron Spencer/Getty Images)

The newly-discovered gaseous planet Kepler-16b orbits it's two stars. NASA's Kepler Mission discoverd the world orbiting two Stars, the larger a K dwarf and the smaller a red dwarf. (Photo by NASA/JPL-Caltech/T. Pyle via Getty Images)

James Doran has created two epic dragon sculpture. The first, perched on a dead tree, is called ‘The Wyvern in the Baobabs’ (a wyvern is a type of dragon with two legs and two wings). The other, ‘Wyvern’s Folly,’ is perched on a gazebo made from reclaimed steel and recycled water bottles.

Canadian-Israeli film director Simcha Jacobovici holds two nails during a press conference on April 12, 2011. Jacobovici believes that the two nails discovered in a Jerusalem cave were used in the crucifixion of Jesus Christ. Jacobovici claims that the nails were tracked to an archeology laboratory in Tel Aviv, and though cannot be 100 per cent certain that they are the nails used in the crucifixion of Jesus, he claims if “you put two and two together and they seem to imply that these are the nails”. Experts at the Israel Antiquities Authority though cast doubt on Jacobovici's claims, and suggest that nails are commonly found in such locations. (Photo by Lior Mizrahi/Getty Images)

A fight between two female musk oxen, Norway, 2021. The image was captured in Norway’s Dovrefjell national park, where the musk ox (Ovibos moschatus) was reintroduced several years ago for its conservation. It is normal for males of this species to engage in fierce battles during the mating season but unusual for two females. (Photo by Miquel Angel Artús Illana)

“People of the River”. This is a Karo tribe family; father, mother, two sisters and two brothers. The tribe, who live along the Omo River in east Africa, incorporate rich symbolism into their rituals by using ornate body art, headdresses and body scarification to express beauty and significance. (Photo by Jatenipat Ketpradit/International Portrait Photographer of the Year)

Two three-month-old female white Bengal tiger cubs play with a zoo keeper in their enclosure at the Buenos Aires' Zoo, in Argentina, on April 17, 2014. Captive white Bengal tiger Cloe, gave birth to three cubs – two females and one male – on January 14, 2014. (Photo by Juan Mabromata/AFP Photo)

Two Bunny Girls from the Playboy Club and two Penthouse Pets from the Penthouse Club prepare to take part in the annual Good Friday waiters and waitresses race in Battersea Festival Gardens, London, 28th March 1972. (Photo by Ian Showell/Keystone/Hulton Archive/Getty Images)