A Humboldt penguin stands on weighing scales whilst being photographed by members of the press during a photocall at the annual weigh-in at London Zoo in London, Britain, 24 August 2016. Every animal that is in the zoo is weighed and measured and the statistics recorded so the data can be shared with zoos across the world. (Photo by Hannah McKay/EPA)

A vendor (C) cuts slaughtered dogs for sale at his roadside stall in Duong Noi village, outside Hanoi December 16, 2011. While animal rights activists have condemned eating dog meat as cruel treatment of the animals, it is still an accepted popular delicacy for some Vietnamese, as well in some other Asian countries. Duong Noi is well-known as a dog-meat village, where hundreds of dogs are killed each day for sale as popular traditional food. Dog-eating as a custom is rooted in Vietnam and was developed as a result of poverty. One kilogram of dog meat costs about 130,000 dongs ($6.2). (Photo by Reuters/Kham)

Activists attend a parade to demand rights of gender equality to LGBT community members in Santiago, Chile, November 25, 2017. (Photo by Ivan Alvarado/Reuters)

A Chinese man wears a mask to protect against pollution as he waits at a red light while commuting to work in heavy smog on December 8, 2015 in Beijing, China. The Beijing government issued a 'red alert' for the first time since new standards were introduced earlier this year as the city and many parts of northern China were shrouded in heavy pollution. Levels of PM 2.5, considered the most hazardous, crossed 400 units in Beijing, lower than last week, but still nearly 20 times the acceptable standard set by the World Health Organization. The governments of more than 190 countries are meeting in Paris to set targets on reducing carbon emissions in an attempt to forge a new global agreement on climate change. (Photo by Kevin Frayer/Getty Images)

Attnedees dressed in Zombie outfits walk down the Gaslamp Quarter outside of the 2015 Comic-Con International in San Diego, California July 8, 2015. (Photo by Sandy Huffaker/Reuters)

A woman prays at the edge of a river during a protest against the building of a pipeline near the Standing Rock Indian Reservation near Cannonball, North Dakota, U.S. November 2, 2016. (Photo by Stephanie Keith/Reuters)

An athlete dressed as a clown jumps into the Mediterranean sea as he takes part in the Copa Nadal in the Spanish port of Barcelona in Barcelona, Spain, Sunday, December 25, 2016. The Copa Nadal (Christmas Cup) is a traditional swimming competition that takes place in Barcelona every December 25th, where participants swim 200 meters in the open sea in the port of Barcelona. (Photo by Manu Fernandez/AP Photo)

Wild weather drenches tourists, Sydney, Australia on March 7, 2017. A series of photographs as tourists take a soaking on Sydney's iconic Manly Ferry sailing big swells near Sydney's North Head. The Weather Bureau warns of large and powerful surf conditions expected to be hazardous for coastal activities such as rock fishing, swimming and surfing. (Photo by Hugh Peterswald/Pacific Press via ZUMA Wire/Rex Features/Shutterstock)