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)

Željava Air Base, situated on the border between Croatia and Bosnia and Herzegovina under Plješevica Mountain, near the city of Bihać, Bosnia, was the largest underground airport and military air base in the former Yugoslavia, and one of the largest in Europe. (Photo by Thomas Windisch/Exclusivepix Media)

A pile of destroyed cars of teachers sits outside Briarwood elementary school in Oklahoma City, Oklahoma May 22, 2013. Rescue workers with sniffer dogs picked through the ruins on Wednesday to ensure no survivors remained buried after a deadly tornado left thousands homeless and trying to salvage what was left of their belongings. Curvature of horizon in the photo is due to an ultra-wide angle lens. (Photo by Rick Wilking/Reuters)

The new MacBook Pro is shown during the keynote address at the Apple 2012 World Wide Developers Conference (WWDC) at Moscone West on June 11, 2012 in San Francisco, California. This is Apple’s latest flagship laptop featuring an updated processor and a super high resolution screen that features 5.1 million pixels – 3 million more than a typical high-definition television.

A woman with disability communicates with sign language as they sit and demonstrate with Disability Activists Forum demanding their rights from the Bengal Government, during the International Day of Persons with Disabilities in Kolkata, Eastern India, 03 December 2021. The International Day of Persons with Disabilities is annually observed on 03 December with an objective to promote an awareness of disability issues, the fundamental rights of persons with disabilities and integration of persons with disabilities in the mainstream of each aspect of the social, political, economic and cultural status of their communities. (Photo by Piyal Adhikary/EPA/EFE)

Pedestrians wear masks as smoke and haze from bushfires in New South Wales blankets the CBD in Sydney, Australia, 10 December 2019. The New South Wales environment department says visibility across east and southwest Sydney was at a “hazardous” level on Tuesday morning, while air quality was poor in southwest Sydney and hazardous in northwest Sydney. (Photo by Steven Saphore/EPA/EFE)

Anti-government protesters take cover during clashes with security forces who are firing tear gas from La Carlota airbase in Caracas, Venezuela, Wednesday, May 1, 2019. Opposition leader Juan Guaidó called for Venezuelans to fill streets around the country Wednesday to demand President Nicolás Maduro's ouster. Maduro is also calling for his supporters to rally. (Photo by Ariana Cubillos/AP Photo)

Festival goers pose for photographers on the third day of Glastonbury Festival at Worthy Farm, Somerset, England, Friday, June 28, 2019. Temperatures are expected to soar over the weekend as a heatwave hits parts of Europe, while the festival runs for five days and is one of the largest events of its kind in the world. (Photo by Joel C. Ryan/Invision/AP Photo)