Supporters of Venezuela's President Nicolas Maduro take part in a rally in support of the government in Caracas, Venezuela on May 20, 2019. (Photo by Ivan Alvarado/Reuters)

A male red deer with antlers covered in bracken, walks through undergrowth in Richmond Park in south west London, October 3, 2014. Over 600 red and fallow deer roam in the largest of London's Royal Parks, and have their numbers managed in an annual cull each November and February. (Photo by Toby Melville/Reuters)

Russia's synchronised swimming duet Aleksandr Maltsev (L) and Darina Valitova compete in the Mixed Duet Technical preliminary during the synchronised swimming competition at the 2015 FINA World Championships in Kazan on July 25, 2015. (Photo by Christophe Simon/AFP Photo)

A handout photograph provided by Brian Kubicki of Costa Rican Amphibian Research Center on 26 April 2016 shows a “Crystal frog”, Hyalinobatrachium dianae (H. diane). This frog was discovered by US biologist Brian Kubicki and Costa Ricans Stanley Salazar and Robert Puschendorf in a rainy forest of Costa Rican caribbean after 40 years without notice of any new example of this kind. (Photo by Brian Kubicki/EPA/Costa Rican Amphibian Research Center)

A man looks at a photograph by French photographer Robert Doisneau entitled “The Fate Line: Pablo Picasso at Vallauris, 1952” during the presentation of the photo-exhibition “Picasso, photographer's gaze”, on June 5, 2019 at the Picasso Museum in Barcelona. (Photo by Lluis Gene/AFP Photo)

Photographer Jim Zielinski from Florida, USA, captured this hilarious moment when a squirrel spied a tasty treat inside a novelty horse's head bird feeder in his back garden. (Photo by Jim Zielinski/Caters News)

A mother bear takes a dip in the water to cool off in the warm summer sun but refuses to leave her three youngsters behind – so they climb aboard her back. (Photo by Jon Langeland/Solent News & Photo Agency)

An African giant pouched rat sniffs for traces of landmine explosives at APOPO's training facility in Morogoro on June 17, 2016. APOPO trains the rats to detect both tuberculosis and landmines at its facility. Every year landmines kill or maim thousands of people worldwide. The trained rats sniff for explosive and so are able to detect the presence of landmines far faster than conventional methods which involve metal detection. (Photo by Carl De Souza/AFP Photo)