Marine biologist Simon Pierce, who studies whale sharks, happened to be in the right place at the right time to capture amazing photo off Cancun, Mexico. (Photo by Simon Pierce/Mercury Press/Caters News)

A view of balloon depicting an Alebrije, is seen at the 14th Solar Balloon Festival in Envidago December 31, 2014. According to the festival organizers, the Alebrije balloon will be largest replica of an Alebrije. This year features a theme on Mexican history and culture, organizers added. (Photo by Fredy Builes/Reuters)

Natalia Arango works with her mine detector in a zone of landmines planted by rebels groups near Sonson in Antioquia province, November 19, 2015. Women's work takes on a nontraditional meaning for fifteen Colombian women who work to rid the Antioquia Mountains of deadly landmines as the country edges closer to a peace agreement with Marxist rebels to end over a decade of conflict which has claimed 220,000 lives. (Photo by Fredy Builes/Reuters)

Animal rights activists perform, demanding the abolition of bullfights, during a demonstration in Medellin, Colombia February 11, 2018. The Colombian Constitutional Court overruled on February 7, 2018, a judgment that allowed to hold a referendum regarding bullfights. (Photo by Fredy Builes/Reuters)

Racegoers during Ladies Day at the Grand National Festival at Aintree Racecourse on April 13, 2018 in Liverpool, England. (Photo by Mercury Press)

In this May 4, 2014 photo, a miner holds an amalgam of mercury and gold he mined after working a 28-hour shift at an illegal gold mining process, in La Pampa, in Peru's Madre de Dios region. Thousands of artisanal gold miners sweat through the long shifts and endure, for a few grams of gold, the perils of collapsing earth, limb-crushing machinery and the toxic mercury used to bind gold flecks. (Photo by Rodrigo Abd/AP Photo)

Colombian Jahn Fredy Duque, dressed as superhero “Spiderman”, performs on the streets in Bogota, Colombia on April 24, 2017. Duque hangs a white cloth 26 meters long – his cobweb – from a bridge near the international center of Bogota, where he performs in the street for a livelihood. (Photo by Raul Arboleda/AFP Photo)

It's often said that pets and their owners can start to look alike, but these adorable photographs take the old mantra to a new extreme. They are the work of Svetlana Valyiskaya (27), from St Petersburg, who snaps pets in everyday poses in her spare time from her job as a commercial photographer. The vibrant costumes and scenes, which Svetlana designs herself, have made the photos a hit in her native Russia – and it's not hard to see why. She said: “I really love animals, they are loyal, faithful and true and always interesting to work with – plus they never criticise the photographs afterwards”. (Photo by Svetlana Valyiskaya/Mercury)