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)

Birds sit on the back of a zebra in the Nairobi National Park, near Nairobi, Kenya, November 21, 2018. (Photo by Baz Ratner/Reuters)

Long Exposure pictures showing Mount Sinabung spewing out hot lava on August 2, 2017 in Karo, Indonesia. Sinabung located in North Sumatra Province roared back to life in 2010 for the first time in 400 years. After another period of inactivity it erupted once more in 2013, and has remained highly active since. (Photo by Albert Damanik/Barcroft Images)

A colourful morning sunrise on Christmas Eve at Victoria Tower on Castle Hill, West Yorkshire, England on December 24, 2017. The history of human activity on the Castle Hill goes back over 4000 years. The site was developed as an iron age hill fort, surrounded by defensive ditches and ramparts. In the Middle Ages there was a castle on the hill, of which the well remains. The present tower was built to commemorate Queen Victoria's Diamond Jubilee of 1897. (Photo by Charlotte Graham/ZUMA Wire/Rex Features/Shutterstock)

A hiker walks in the Zillertal Alps during an autumn day near the village of Ginzling, Austria, October 15, 2019. (Photo by Lisi Niesner/Reuters)

An otter reaches for a snack from a customer at an otter cafe in Tokyo. Asian small-clawed otters are increasingly popular as novelty pets, particularly in Japan. Now international trade in the species may be banned. (Photo by Noriko Hayashi/The New York Times)

Medical personnel jump in the COVID-19 unit at the CHR Centre Hospitalier Regional de la Citadelle Hospital, during the coronavirus disease (COVID-19) outbreak, in Liege, Belgium, April 22, 2020. (Photo by Yves Herman/Reuters)

The endangered kea is the world’s only alpine parrot, and one of the most intelligent birds. They show no fear of humans and are thieves and pranksters. The parrot is seen in the Whakaari conservation area, near Glen Orchy in the Otago region of New Zealand, a place where historic huts and mining relics are surrounded by stunning mountains covered in tussock. (Photo by Murdo MacLeod/The Guardian)