A man driving a vintage car reacts as he passes by crabs crossing a highway on their way to spawn in the sea in Playa Giron, Cuba on April 25, 2017. Each year, after the first spring rains, millions of red, yellow and black landcrabs march for days from the surrounding forests to the bay on Cuba's southern coast to spawn in the sea. (Photo by Alexandre Meneghini/Reuters)

Storm chasing photographer Mike Hollingshead makes a living following the worst storms in America, from snarling tornadoes chewing up the Kansas farmland to supercell thunderstorms massing over the Dakotas. His style is to get right in the path of the storm. While he says it’s less scary than you think – because most of the storm consists of heavy rain – it’s still extremely stressful. Photo: Vivid sunset under severe storm in central Nebraska August 17, 2005. (Photo by Mike Hollingshead)

A 15-year-old girl denied a horse from her parents has turned to a cow to fulfil her riding dreams. Teenager Regina Mayer, from southern Germany, is able to ride her cow, Luna. She has even trained her bovine pet to soar over a beer-crate hurdle like a regular show jumper. Why, you may well ask, when most cow-owners are surely content to let the creatures chew and lactate and sit down to indicate the imminent arrival of rain? Well, Regina's parents wouldn't let her have a horse.

People brave the wind on the waterfront of Victoria Habour as Typhoon Haima approaches Hong Kong, Friday, October 21, 2016. Typhoon Haima churned toward southern China on Friday after smashing into the northern Philippines with ferocious wind and rain, triggering flooding, landslides and power outages. (Photo by Vincent Yu/AP Photo)

A wild water buffalo eats tree branches standing in flood water at the Pobitora wildlife sanctuary in Pobitora, Morigaon district, Assam, India, Thursday, July 16, 2020. Floods and landslides triggered by heavy monsoon rains have killed dozens of people in this northeastern region. The floods also inundated most of Kaziranga National Park, home to an estimated 2,500 rare one-horned rhinos. (Photo by Anupam Nath/AP Photo)

Tim Laman is a field biologist and wildlife photojournalist. His pioneering research in the rain forest canopy in Borneo led to a PhD from Harvard and his first National Geographic article in 1997. Since then, he has pursued his passion for exploring wild places and documenting little-known and endangered wildlife by becoming a regular contributor to National Geographic. He has eighteen articles to his credit to date, all of which have had a conservation message. Some have focused on endangered species such as Orangutans or Hornbills, while others, such as a series of articles on Conservation International’s Biodiversity Hotspots, have highlighted regions under intense pressure.

A cenote is a natural phenomenon, a sinkhole in the Earth’s surface. The Yucatan Peninsula in Mexico has an estimated 7,000 cenotes because it is primarily made up of porous limestone. For millions of years, rainfall slowly ate away at the limestone and a huge system of underground caves and caverns was formed. Many filled with water from rain or from the underground water table. When the roof of a water filled cave collapses, a cenote is born. The water found in a cenote may be fresh water, salt water, or both. Structurally it may be completely open, like a lake, almost completely closed with just a small opening at the top, or somewhere in between.

The sign above the door of restaurant and hotel “Am Paulusbogen” is partially submerged in the flooded centre of the Bavarian town of Passau, about 200 km (124 miles) north-east of Munich June 3, 2013. (Photo by Michaela Rehle/Reuters)