A schoolgirl collects rubbish from Karachi's Clifton beach early morning April 22, 2013, during a cleaning campaign as part of the commemoration of Earth Day. (Photo by Akhtar Soomro/Reuters)

In this undated photo provided by LittleFriendsPhoto.com via Six Flags Discovery Kingdom, Kai, a 17-year-old male California sea lion at Six Flags Discovery Kingdom in Valejo, Calif. peers into the lens of photographer Seth Casteel, known for his “Underwater Dogs” photo series. ... (Photo by Seth Casteel/AP Photo/LittleFriendsPhoto.com via Six Flags Discovery Kingdom)

“Honorable Mention”. An Indian rhinoceros, far from home and stuck inside with late-winter blues at the Toronto zoo. Photo location: Toronto, Ontario, Canada. (Photo and caption by Stephen De Lisle/National Geographic Photo Contest)

People take pictures of deer in the Phoenix Park in Dublin, Ireland December 5, 2016. (Photo by Clodagh Kilcoyne/Reuters)

Winners of a competition enjoy a meal 450ft up on the roof of a central London skyscraper on August 21, 2018, as Deliveroo recreates “Lunch Atop a Skyscraper”, the photograph taken during the construction of the Rockefeller Center in New York City, 1932. (Photo by Jonathan Brady/PA Images via Getty Images)

A chimpanzee looks in the direction of a camera at the Gut Aiderbichl Sanctuary for Traumatized Chimpanzees and other Primates in Gaenserndorf, near Vienna, 17 September 2018. 34 former laboratory chimpanzees of former Austrian pharmaceutical company Immuno AG spend their lives at the Gut Aiderbichl Sanctuary for Traumatized Chimpanzees and other Primates since 2009. (Photo by Christian Bruna/EPA/EFE)

A Palestinian man argues with an Israeli soldier during clashes over an Israeli order to shut down a Palestinian school near Nablus, in the occupied West Bank, October 15, 2018. (Photo by Mohamad Torokman/Reuters)