“A Snail's Life”. Photographer Vyacheslav Mischenko captures gorgeous macro photographs of snails near his hometown of Berdichev, Ukraine. After being taught to hunt for mushrooms as a child, Vyacheslav has grown up with a keen eye for spotting critters on the forest floor. Here, a snail takes shelter while perching on a leaf. (Photo by Vyacheslav Mischenko/Caters News)

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)

Rescue workers stand near dead bodies washed ashore in Ton Sai Bay in Thailand's Phi Phi island in this December 28, 2004 file photo. On December 26, 2004, a magnitude 9.15 quake off the coast of Indonesia's Aceh province triggered an Indian Ocean tsunami that killed around 226,000 people in Indonesia, Sri Lanka, India, Thailand and nine other countries. (Photo by Luis Enrique Ascui/Reuters)

Behaviour: Mammals category. Giant Gathering by Tony Wu, USA. Dozens of sperm whales mingled noisily off Sri Lanka’s northeast coast, stacked as far down as Tony could see. This was a congregation of dozens of social units, like a gathering of the clans. Aggregations like this could be a critical part of the whales’ rich social lives but are rarely reported. Some two thirds of the population was wiped out before commercial whaling was banned in 1986. This kind of major gathering could be “a sign that populations are recovering”, says Tony. (Photo by Tony Wu/Wildlife Photographer of the Year 2017)

Young Ukrainians dance at nightclub House of Meteorologists, May 23, 2014. Sunday's upcoming election in Ukraine has not only exposed the divide between east and west, but between old and young. Unlike their elders, younger people have no memory of Soviet life, and most see themselves as Ukrainian. (Photo by Evelyn Hockstein/The Washington Post)

“Untitled”. Hong Kong, Wan Chai area, on March 7, 2013. (Photo by Jerry Lee)

This is one boy's amazing picture diary of his pet rodents doing very human tasks. Colin Mclaughlin, from Maryland, USA, has created a hilarious photo collection of his pet guinea pigs, Chester and Sam. (Photo by Colin Mclaughlin/Caters News)