A rugby fan adjusts his latex mask at the rugby sevens tournament in Hong Kong on March 29, 2014. (Photo by Philippe Lopez/AFP Photo)

American actor and politician Ronald Reagan stands behind his wife, actor Jane Wyman, who sits down to dinner, circa 1940s. She is seated between two unidentified men, both in military uniforms adorned with Arms Qualification medals, the man on the right with Sharpshooter and Marksman badges and the man on the left, a Captain, with Expert and Sharpshooter badges. Reagan wears a military uniform with Cavalry branch insignia and Wyman wears a black dress with stranded pearl necklace, and a black hat with a veil. (Photo by Hulton Archive/Getty Images)

(L-R) Maria Silva, Milena Cortes, Maria Arteaga, Jackeline Bastidas and Gissy Abello pose for a picture at the Famproa dogs shelter where they work, in Los Teques, Venezuela, August 25, 2016. Venezuelans struggling to feed their families let alone their pets are dumping animals on the streets, in parks and at makeshift homes overrun with scrawny animals amid an economic crisis. An hour from Caracas in Los Teques, hundreds of dogs bark and run around the streets scavenging for food outside a makeshift shelter. (Photo by Carlos Garcia Rawlins/Reuters)

Traveling Chairso n Hakone Road. (Photo by Kusakabe Kimbei)

North Koreans wave as Hughes MD-500 helicopters fly past during an aerial display on Saturday, September 24, 2016, in Wonsan, North Korea. North Korea on Saturday opened an air festival featuring sky diving, demonstrations by its air force and lots of beer to promote a newly renovated and upgraded commercial airport in the coastal city of Wonsan that it hopes will draw for foreign tourists. (Photo by Wong Maye-E/AP Photo)

Global wildlife populations will decline by 67% by 2020 unless urgent action is taken to reduce human impact on species and ecosystems, warns the biennial Living Planet Index report from WWF (World Wide Fund for Nature) and ZSL (Zoological Society of London). From elephants to eels, here are some of the wildlife populations most affected by human activity. Here: The maned wolf is among the large mammals in the Brazilian Cerrado that are threatened by the increasing conversion of grasslands into farmland for grazing and growing crops. (Photo by Ben Cranke/Nature Picture Library/Alamy Stock Photo)

Camels graze in front of a spacecraft tracking station ahead of the Soyuz MS-10 upcoming launch at the Baikonur Cosmodrome, Kazakhstan, October 9, 2018. (Photo by Shamil Zhumatov/Reuters)

Indian dancers paint their body like tigers as they perform a Tiger dance during the International day of the Tiger in Calcutta, India, July 29, 2015. Students of Calcutta are taking part in an awareness campaign aiming to draw attention to the threats that tigers face due to habitat loss and poaching. (Photo by Piyal Adhikary/EPA)