The fourth annual BigPicture Natural World Photography Competition aims to celebrate the diversity of life on Earth, and encourages people to protect and conserve it. Here: “The Salmon Catchers”. Terrestrial Wildlife. To capture this view of a mother grizzly bear and her cub, photographer Peter Mather set up a camera trap on a log that he knew the bears tended to traverse while fishing for salmon, in the Yukon River watershed in Canada. (Photo by Peter Mather/BigPicture Natural World Photography Competition 2017)

Hooded demonstrators vandalise a shop window in Mexico City, during the commemoration of the 50th anniversary of the 1968 Tlatelolco student massacre, on October 2, 2018. Fifty years ago, Mexican troops opened fire on student demonstrators, killing hundreds just days before Mexico City hosted the 1968 Olympics – one of the darkest episodes in a year of global turbulence. (Photo by Ronaldo Schemidt/AFP Photo)

Actresses Zelda Williams and Kelly Monaco attend Nintendo's celebration of the launch of Super Mario 3D Land at Siren Studios on November 3, 2011 in Hollywood, California. (Photo by Jason Merritt/Getty Images for Nintendo)

“The Waterloo Cup was a coursing event. The three day event was run annually at Great Altcar in Lancashire, England from 1836 to 2005 and it used to attract tens of thousands of spectators to watch and gamble on the coursing matches. It was founded by William Philip Molyneux, 2nd Earl of Sefton, and, originally, was supported by his patronage”. – Wikipedia

Photo: A Greyhound races after Hare at the last Waterloo Cup Hare coursing event, February 14, 2005, near Liverpool, England. (Photo by Christopher Furlong/Getty Images)

A woman takes photos of a child on a sports ground covered with hailstones following a hail storm in the Siberian city of Omsk, Russia on June 27, 2023. (Photo by Alexey Malgavko/Reuters)

Egrets stand on a field as an Egyptian farmer plants rice seedling in Egypt's fertile Delta in Tanta, Algharbeya governorate, 100 km from Cairo, Egypt, 22 June 2022. Egyptian Government reduced the planting of some crops that need a massive amount of irrigation water, while the government said it will reduce the rice agriculture area in Egypt, amid fear the Renaissance Dam project in Ethiopia could affect the amount of River Nile water reaching Egypt. (Photo by Khaled Elfiqi/EPA/EFE)

A Nepalese devotee bows in front of a cow during the 'Gai Puja', also known as the Cow Worship Day, as part of the Tihar festival in Kathmandu, Nepal, 11 November 2015. The Tihar festival is the second most important event for Nepalese Hindus. During the celebrations people worship cows, considered the incarnation of Lord Laxmi, the god of wealth. (Photo by Narendra Shrestha/EPA)

Those lights are actually bioluminescent shrimp, better known as sea fireflies, or, in Japan, as “umibotaru”. Visible every year from May until the end of October, they live in the sand around very shallow sea water and are often seen floating between the extremes of high and low tides. Here: Bioluminescent sea fireflies glittering like diamonds on the rocks and sand. Okayama, Japan. July 2016. (Photo by Trevor Williams/Jonathan Galione/Getty Images)