A new book published by the UK Natural History Museum showcases some of the most memorable underwater photographs taken over the last few decades in its annual wildlife photographer of the year competition. Here: Giant gathering by Tony Wu. “The first indication that something extraordinary was going on were the blows, huge numbers of them – the exhalations of huge numbers of whales. Entering the water, the photographer witnessed an extraordinary scene”. (Photo by Tony Wu/Unforgettable Underwater Photography/NHM)

A Green Crowned Brilliant is pictured at a Hummingbird feeding station on January 15, 2016 in Alajuela Costa Rica. Of the 338 known species of Hummingbird worldwide there are around 50 in Costa Rica. Hummingbirds are named for the distinctive sound made by their tiny beating wings, and are admired for their vibrantly coloured iridescent plumage. Their ability to hover, with wings beating between 12 and 90 times a second, and to fly backwards makes them different from all other birds. (Photo by Dan Kitwood/Getty Images)

Newly-wed Syrian couple Nada Merhi, 18, and Hassan Youssef, 27, have their wedding pictures taken in front of a heavily damaged building in the war ravaged city of Homs on February 5, 2016. A Syrian photographer thought of using the destruction of Homs to take pictures of newly wed couples to show that life is stronger than death. (Photo by Joseph Eid/AFP Photo)

Sandra Brown, 40, rides the Skyslide on the 69th and 70th floors of the U.S. Bank Tower which is attached to the OUE Skyspace LA observation deck in downtown Los Angeles, California, U.S. June 20, 2016. (Photo by Lucy Nicholson/Reuters)

The golden monkey (Cercopithecus kandti) is a species of Old World monkey found in the Virunga volcanic mountains of Central Africa, including four national parks: Mgahinga, in south-west Uganda; Volcanoes, in north-west Rwanda; and Virunga and Kahuzi-Biéga, in the eastern Democratic Republic of Congo. It is restricted to highland forest, especially near bamboo.

“The Portuguese Water Dog is a breed of working dog as classified by the American Kennel Club. Portuguese Water Dogs are originally from the Portuguese region of the Algarve, from where the breed expanded to all around Portugal's coast, where they were taught to herd fish into fishermen's nets, to retrieve lost tackle or broken nets, and to act as couriers from ship to ship, or ship to shore. Portuguese Water Dogs rode in bobbing fishing trawlers as they worked their way from the warm Atlantic waters of Portugal to the frigid fishing waters off the coast of Iceland where the fleets caught cod to bring home. Portuguese Water Dogs were often taken with sailors during the Portuguese discoveries”. – Wikipedia

Photo: Kix, a Portuguese Water Dog , enjoys a walk around the muddy fields near his home before the grooming and preparation starts for this years Crufts on March 3, 2009 in Telford, England. (Photo by Christopher Furlong/Getty Images)

Tibetan students play at a class break at the Xiangnong primary school on April 15, 2005 in Kangding County of Ganzi Tibetan Autonomous Prefecture, Sichuan Province, southwest China. There is only one teahcer in the Tagong Village, 12 Tibetan students get free education from him in Xiangnong primary school. (Photo by China Photos/Getty Images)

This undated photo provided by the U.S. Fish and Wildlife Service shows two island foxes in Channel Islands National Park, Calif. Three fox subspecies native to California's Channel Islands were removed from the list of endangered species Thursday, August 11, 2016, in what federal officials have called the fastest recovery of any mammal listed under the Endangered Species Act. (Photo by Chuck Graham/U.S. Fish and Wildlife Service via AP Photo)