Revellers dressed as zombies take part in an enactment of the running of the bulls a day before the start of the San Fermin festival in Pamplona, northern Spain, July 5, 2016. (Photo by Eloy Alonso/Reuters)

Kea are the only true alpine parrots in the world and thrive as cunning opportunists in the freezing conditions of the Southern Alps. Kea are thought to have developed their wide array of food-finding strategies during the last great ice age, where they learned to adapt using their unusual powers of curiosity. (Photo by Tom Walker/BBC Pictures/The Guardian)

A peformance artist attends an election rally for Cameroon presidential candidate for the opposition Univers party, Cabral Libii in Yaounde, Cameroon 06 October 2018. Africa's oldest president Paul Biya who has been in power since 1982 is up against eight candidates when voters go to the polls 07 October 2018. 6.9 million registered voters will head to the polls but marginalised anglophone separatists in the North West and South West of the country threaten to disrupt the elections. (Photo by Nic Bothma/EPA/EFE)

Young Ukrainians dance at nightclub House of Meteorologists, May 23, 2014. Sunday's upcoming election in Ukraine has not only exposed the divide between east and west, but between old and young. Unlike their elders, younger people have no memory of Soviet life, and most see themselves as Ukrainian. (Photo by Evelyn Hockstein/The Washington Post)

Marionettes backstage before a performance at the Bob Baker Marionette Theater in Los Angeles, California October 17, 2014. The playhouse started in 1960, has 2,000 marionettes and is the oldest continually running marionette theater in the U.S. It was recently bought by a developer who wants to turn the historic landmark into a 104-unit apartment complex. (Photo by Lucy Nicholson/Reuters)

M42 Subtle V1 cropped. One of the most well-known astronomical objects in our universe is the Orion Nebula and this image depicts the wider region of the Orion Molecular Cloud Complex that is its home. This complex also includes another popular target for astrophotographers, the Horsehead Nebula, as well as Barnard’s Loop and the Running Man Nebula, which can be seen to the left of this photograph. (Photo by Patrick Gilliland)

“Basunga”. Basunga (3 weeks-old newborn with albinism) is happily sleeping with his cousin. For now, he does not yet realize the difficulties he will face to integrate into the Congolese society as a PWA. The success of his integration will greatly depends of how he accepts himself and his skin condition a and how educated he will be. Photo location: Kinshasa, Congo RDC. (Photo and caption by Patricia Willocq/National Geographic Photo Contest)

Family and friends sit in a vehicle trailer, where they will spend the night, near the enclosure for buffalos awaiting sacrifice on the eve of the sacrificial ceremony for the “Gadhimai Mela” festival in Bariyapur November 27, 2014. The festival renowned for its large number of animal sacrifices, is held every five years at the Gadhimai Temple where devotees from Nepal and bordering India will sacrifice buffaloes, goats and birds while offering prayers to Gadhimai, the goddess of power. (Photo by Navesh Chitrakar/Reuters)