A robin perches on a spade handle in a garden on a rainy day in Lixwm, north Wales. Researchers said this week that when European robins are subjected to human-produced noise, their behaviour changes. (Photo by DGDImages/Alamy Live News)

A person falls down stairs while sledding in Central Park as snow falls in Manhattan, New York City, U.S., February 7, 2021. (Photo by Andrew Kelly/Reuters)

Libyan leader Muammar Gaddafi attends the inauguration ceremony of Jacob Zuma on May 9, 2009 in Pretoria, South Africa. Jacob Gedleyihlekisa Zuma is South Africa's fourth President since the end of apartheid. (Photo by Foto24/Gallo Images/Getty Images)

A red squirrel sniffs out nuts inside Christmas stockings as part of the festive celebrations and enrichment programme at Wildwood Escot Park in Ottery St Mary, Devon, United Kingdom on December 17, 2020. (Photo by Ben Birchall/PA Images via Getty Images)

Elizabeth Svensson (right), 35 and Klaudia Zakrzewska, 27, from London, arrive back in the UK at Heathrow Terminal 2, after being on holiday in Dubai for 15 days, during England's third national lockdown to curb the spread of coronavirus on Friday January 29, 2021. (Photo by Yui Mok/PA Images via Getty Images)

These images of young children training were taken at a gymnastics summer camp in Bozhou, Anhui province, China on July 28, 2015. Children with promise are selected to attend, and their families hope training will not only benefit their children physically but also increase ‘willpower’, according to China News Service. (Photo by ChinaFotoPress/ChinaFotoPress via Getty Images)

Aurora Borealis, or Northern Lights, shine over the plane wreck of a US Navy airplane – a Douglas Super DC-3 – on the Black Beach in Solheimasandur, south Iceland on January 18, 2018. (Photo by Owen Humphreys/PA Images via Getty Images)

Wax figures, including Prime Minister Boris Johnson, US President Donald Trump and Taylor Swift, in the entrance line at Madame Tussaud's in London on July 30, 2020, as the attraction prepares to reopen to the public following the easing of lockdown restrictions in England. (Photo by Kirsty O'Connor/PA Images via Getty Images)