Employees work at a sorting centre of Zhongtong (ZTO) Express ahead of the Singles Day shopping festival, Chaoyang District, Beijing, November 8, 2015. On China's giant Singles Day internet shopping festival, the country's delivery firms are stretched so thin that they are looking for tie-ups, listings and new investors to husband their resources. (Photo by Jason Lee/Reuters)

Greyhounds compete during a race at Santiago city, March 8, 2014. With over 100 years of history, greyhound racing attracts people mainly from rural areas of Santiago every weekend. Some dogs come from Argentina, the United States and Ireland and can develop a speed of up to 80 kilometers per hour on a straight running track of about 200 meters, according to organisers. Bets range from $2 to $1,000 per race, offering a livelihood for breeders and gamblers. (Photo by Ivan Alvarado/Reuters)

A busy rush hour sees thousands of commuters climbing on board a train – as well as holding onto its sides and sitting on the roof before it speeds off. Men, women and children climb and are pulled up onto the roof of the train, which is around 12ft (3.6m) high, as they try to find themselves a space. With no seats available inside, many commuters decide to take the risk and choose a rooftop view for their journey out of Dhaka city, in Bangladesh. (Photo by Yousuf Tushar/Solent News & Photo Agency)

Wrestler known as Gio Malkriado (top) fights with a fluorescent tube with wrestler Ciclope during an extreme wrestling fight at a temporary wrestling ring inside a car wash in Tulancingo Hidalgo, Mexico October 8, 2016. When the time comes for the so-called Extreme Star Fight, six wrestlers climb into the ring. Once the fighting begins, anything goes. They bash each other with chairs and long neon lights, causing small explosions and scattering tiny pieces of glass everywhere. (Photo by Carlos Jasso/Reuters)

Brides and grooms sit on top of an Indonesian Army vehicle during a mass wedding ceremony organized in Jakarta, Indonesia, Wednesday, January 28, 2015. More than 5000 couples participated on a mass wedding ceremony to legalized the previous religious marriage ceremonies. Most of the couples have not officially registered their marriage for economic reasons as it cost up to 500,000 IDR (35 euro) to legalized a marriage. The ceremony organized by Rajawali Foundation. (Photo by Achmad Ibrahim/AP Photo)

Hailey Hanestad thinks nothing about nuzzling up to the animal, called Wiley, and even dozes off with him on her bed. Wiley has been a treasured member of the family since being rescued by Hailey's dad, Rick, three years ago. Today he's thought to be just one of two coyotes in the US that have become domesticated after being born in the wild. Photo: Coyote Wiley sniffs Hailey, 8, at their home. (Photo by Barcroft Media)

“Glenfinnan Viaduct is a railway viaduct on the West Highland Line in Glenfinnan, Lochaber, Highland, Scotland. It was built between 1897 and 1901. Located at the top of Loch Shiel in the West Highlands of Scotland, the viaduct overlooks the Glenfinnan Monument and the waters of Loch Shiel”. – Wikipedia

Photo: A view of the Glenfinnan Viaduct on March 30, 2012 in Glenfinnan, Scotland. Built by Sir Robert McAlpine, the single track viaduct that is made up of 21 arches is considered to have been one of the largest engineering projects of its time. Today, it is still used by ScotRail and was recently used for scenes in three of the Harry Potter films. (Photo by Jeff J. Mitchell/Getty Images)