A photographer could bear-ly believe his eyes when a bear started waving at him. The friendly animal wandered to the front of his enclosure before sitting back in full view of zoo guests. He then lifts his powerful paw and excitedly waves in an almost human-like way at his new audience. The hilarious encounter was captured by keen photographer Andrey Slepnev, 31, while on a trip to Madrid Zoo, Spain on March 24, 2016. (Photo by Andrey Slepnev/Caters News)

Strokkur geyser against cloudy sky at sunset. Strokkur is a fountain geyser located in a geothermal area beside the Hvítá River in Iceland in the southwest part of the country, east of Reykjavík. It is one of Iceland's most famous geysers, erupting once every 6–10 minutes. Its usual height is 15–20 m, although it can sometimes erupt up to 40 m high. (Photo by Teatsche Dijkhuis/Getty Images/EyeEm)

A man holds up for a picture a one hundred trillion Zimbabwean dollars note inside a shop in Harare, Zimbawe, June 12, 2015. Hyperinflation in Zimbabwe was a period of currency instability that began in the late 1990s shortly after the confiscation of private farms from landowners, towards the end of Zimbabwean involvement in the Second Congo War. During the height of inflation from 2008 to 2009, it was difficult to measure Zimbabwe's hyperinflation because the government of Zimbabwe stopped filing official inflation statistics. However, Zimbabwe's peak month of inflation is estimated at 79.6 billion percent in mid-November 2008. (Photo by Philimon Bulawayo/Reuters)

Ariana Lamcellari, 4, holds a sign at a protest against violence, following the charge of a British police officer in the London kidnapping and murder of Sarah Everard, in Dublin, Ireland on March 16, 2021. (Photo by Clodagh Kilcoyne/Reuters)

People watch as lava flows from an eruption of a volcano on the Reykjanes Peninsula in southwestern Iceland late on Monday, March 29, 2021. Iceland's latest volcano eruption is still attracting crowds of people hoping to get close to the gentle lava flows. The eruption in Geldingadalur, near Iceland's capital Reykjavik, is not seen as a threat to nearby towns and the slow flows mean people can get close to action without too much harm. (Photo by Marco Di Marco/AP Photo)

Belgian yoga teacher Dorien Dierckx, 29 from Brussels enjoys a beer while relaxing in a jacuzzi full of hot water and a mixture of ingredients used to make beer, and where customers can serve their own beer from the tap at the Good Beer Spa in Brussels, Belgium on May 12, 2021. (Photo by Yves Herman/Reuters)

Fog covers the African Renaissance Monument in Dakar, Senegal on February 17, 2021. (Photo by Zohra Bensemra/Reuters)

Two visitors look at an artwork “Home Sweet Home: Pandemic Love 1” created by Hong Kong artist Mak Ying Tung at Art Basel in Hong Kong Wednesday, May 19, 2021. Art Basel, one of the world's most prestigious modern and contemporary art exhibitions, is returning to Hong Kong in its ninth edition. The prestige art fair is hosting 104 galleries from 23 countries and territories. (Photo by Vincent Yu/AP Photo)