A student runs for cover as riot police clash with students during a demonstration on February 29, 2012 in Barcelona, Spain. Student associations have called upon 120,000 students to strike in protest against education cuts recently announced by the Catalan government. (Photo by David Ramos/Getty Images)

Students from St Andrew's University indulge in a tradition of covering themselves with foam to honour the “academic family” on October 20, 2014, in St Andrews, Scotland. Every November the “raisin weekend” which is held in the university's Lower College Lawn, is celebrated and a gift of raisins (now foam) is traditionally given by first year students to their elders as a thank you for their guidance and in exchange they receive a receipt in Latin. (Photo by Jeff J. Mitchell/Getty Images)

Students from John Moores' University celebrate and pose for family photographs as they take part in their degree congregations at Liverpool's Anglican Cathedral on July 13, 2011 in Liverpool, England. Thousands of students are taking part in graduations across Britain and will begin looking for employment. According to recent surveys there are currently 83 graduates chasing every job vacancy. (Photo by Christopher Furlong/Getty Images)

A UCLA student is arrested by Los Angeles Police Department officers after she attempted to escape after eleven student protesters sat in circle in middle of the Westwood and Wilshire boulevard intersection as part of a protest of bank practices and rising fees at public universities on November 9, 2011 in Los Angeles, California. The protest organized by ReFund California was one of several planned at universities around the state. (Photo by Kevork Djansezian/Getty Images)

Cat-Friend vs Dog-Friend, Two Humans Acting Like House Pets

Lucie Clayton instructs pupils in the art of correct posture by balancing a glass and book on their heads at her finishing school in Old Cavendish Street, London. (Photo by William Vanderson/Fox Photos/Getty Images). 25th November 1936

This beautiful set of images capture the moment a young ballet dancer interacts with her four-legged friends against some iconic backdrops including the Church of the Savior on Blood and the Admiralty building in Saint Petersburg. The enchanted photos were taken by Andrey Seliverstov, 59 from Saint Petersburg, Russia. Here: Nine year old Maria Palkina dancing with dogs. (Photo by Andrey Seliverstov/Caters News Agency)

Dan McManus and his service dog Shadow hang glide together outside Salt Lake City, Utah, July 22, 2013. McManus suffers from anxiety and Shadow's presence and companionship help him to manage the symptoms. The two have been flying together for about nine years with a specially made harness for Shadow. (Photo by Jim Urquhart/Reuters)