Students from St Andrews University are covered in foam as they take part in the traditional Raisin Weekend in the Lower College Lawn, at St Andrews in Scotland on October 22, 2018. The “raisin weekend” stems from a gift of raisins (now flour and foam) traditionally given by a first year student to their academic “parents” in gratitude for their guidance. (Photo by Russell Cheyne/Reuters)

Cooler temperatures begin this week as a polar vortex brings much colder conditions with the chance of snow for Snowdonia, Ogwen Valley, North Wales on 22nd October 2018. The Ogwen Valley and Tryfan Mountain looking splendid in the Autumn sunrise. (Photo by DGDImages/Alamy Live News)

Alvine Uva, right, wrestles the winner's sash from the hands of newly-crowned Miss BumBum 2018 Ellen Santana, left after winning the Miss Bumbum Brazil 2018 pageant in Sao Paulo, Brazil on November 5, 2016. (Photo by Splash News and Pictures)

An emotional former President George Bush, sniffs after touching the flag-draped casket of his father, former President George H.W. Bush, during his State Funeral at the National Cathedral, Wednesday, December 5, 2018, in Washington. (Photo by Andrew Harnik/Pool via Reuters)

European bisons (also known as Wisent) at the Bison farm in Muczne, southeastern Poland, 30 December 2018. The Bison farm is a continuation of bison breeding in Bieszczady, which was started in 1963. Here visitors can admire the bison of Bialowieza-Caucasian line, also called the mountain race. The European Bison is the national animal of Poland. (Photo by Darek Delmanowicz/EPA/EFE)

A woman plays with her three dogs at the beach after sunset in Del Mar, California, USA on November 10, 2017. (Photo by Mike Blake/Reuters)

Military policemen take part in an operation at Cidade de Deus favela in Rio de Janeiro, Brazil, on February 01, 2018. (Photo by Mauro Pimentel/AFP Photo)

Boats moored in the middle of Dal lake are silhouetted against the setting sun on January 15, 2018 in Srinagar, the summer capital of Indian administered Kashmir, India. Kashmir, the Muslim majority state, known as the “Paradise on Earth” has for centuries captured the imagination of many writers, poets and film makers and is integral to the tourist trade. Kashmir has been a contested land between nuclear neighbors India and Pakistan since 1947, the year both the countries attained freedom from the British rule. (Photo by Yawar Nazir/Getty Images)