This photo taken on October 20, 2018 shows tourists posing for a photo on a middle of a railway track passing through an old residential district in central Hanoi. (Photo by Nhac Nguyen/AFP Photo)

This undated handout photograph released by Stony Brook University/ Louisiana State University on March 2, 2018, shows an Adélie penguin looking at a drone at breeding colony on Heroina Island, Danger Islands, Antarctica. A thriving “hotspot” of some 1.5 million Adelie penguins has been discovered on the remote Danger Islands in the east Antarctic, surprised scientists announced on March 2, 2018. (Photo by Rachael Herman/AFP Photo/Louisiana State University AND Stony Brook University)

Children of local herders gather at a reindeer camping ground, some 200 km (124 miles) northeast of Naryan-Mar, the administrative centre of Nenets Autonomous Area, far northern Russia, August 2, 2015. People, including local herders and members of their families, gathered at the site to mark Reindeer Day, a professional holiday of reindeer breeding workers, which is celebrated annually on August 2 in the region. (Photo by Sergei Karpukhin/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)

Executive producer Dave Alpert attends the season five premiere of “The Walking Dead” at AMC Universal Citywalk on Thursday, October 2, 2014, in Universal City, Calif. (Photo by John Shearer/Invision for AMC/AP Images)

A Peugeot 408 car is displayed during the 2011 (15th) Shenzhen-Hong Kong-Macao International Auto Show at Shenzhen Convention and Exhibition Center on June 2, 2011 in Shenzhen, Guangdong Province of China. The 6-day Auto Show will be held from June 2 to 7 with total exhibition area of 110,000 square meters. (Photo by ChinaFotoPress/Getty Images)