Snorkellers approach an adult manatee at Three Sisters Spring, Crystal River, Florida. You might imagine that coming face to face with one of these enormous underwater mammals would cause some concern. However, the likelihood is that the rotund creature just wants you to scratch its belly while it floats around happily, as world-renowned underwater photographer Alex Mustard discovered. (Photo by Alexander Mustard/Barcroft Media)

Alan Wilson, Director of James Ritchie & Son clockmakers, founded in 1809, adjusts a clock face at the Cannongate Tobooth to British Summer Time on March 21, 2012 in Edinburgh, Scotland. The Tolbooth, built in 1591, was where tolls and public dues were collected. The clock face dates back to 1820 and replaced an earlier clock from the 17th Century. Clocks will be put forward by one hour on Sunday March 25, 2012 at 1.00am and British Summer Time (BST) will officially start. (Photo by Jeff J. Mitchell/Getty Images)

A woman wearing a face mask rides a bicycle with a child, following an outbreak of the coronavirus disease (COVID-19) in Wuhan, Hubei province, China on February 8, 2021. (Photo by Aly Song/Reuters)

A traditional Chinese opera actress wearing a face shield poses for a picture during Lunar New Year celebrations in Bangkok, Thailand, February 12, 2021. (Photo by Chalinee Thirasupa/Reuters)

American actress Paris Jackson pulls faces at photographers during the “Melbourne Cup” race day festivities in Melbourne, Australia on November 7, 2017. (Photo by Media-Mode/Splash News and Pictures)

Shoppers and commuters in Manchester wearing face masks on February 28, 2020, including plague doctor masks due to the Coronavirus crisis in the UK. (Photo by Mario Forshow/Cavendish Press)

A girl covers her face as she is daubed in colours during the religious festival of Holi inside a temple in Nandgaon village, in the state of Uttar Pradesh, India, March 5, 2020. (Photo by Adnan Abidi/Reuters)

A dog wearing face mask is seen on a street as the country is hit by an outbreak of the novel coronavirus, in Shanghai, China on March 2, 2020. (Photo by Aly Song/Reuters)