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.

People observe the landslide-affected area after the landslide at Lumle village in Kaski district July 30, 2015. Landslides triggered by torrential rain in Nepal swept through villages on Thursday, killing at least 30 people close to the nation's most popular trekking circuit, home ministry officials said. (Photo by Navesh Chitrakar/Reuters)

Graffiti saying “justice” partially seen above flood waters in Asuncion, December 27, 2015. More than 100,000 people have had to evacuate from their homes in the bordering areas of Paraguay, Uruguay, Brazil and Argentina due to severe flooding in the wake of heavy summer rains brought on by El Nino, authorities said on Saturday. (Photo by Jorge Adorno/Reuters)

People splash mud water in a paddy field on National Paddy Day in Tokha village, on the outskirt of capital Kathmandu, Nepal, 29 June 2021. Nepal is celebrating National Paddy Day with various events on 29 June. On this day, known as Asar Pandra, farmers begin the annual rice planting season and mark the day with various festivities such as preparing rice meals with muddy water, mud being a symbol for a prosperous season. Sixty percent of Nepal's agriculture industry relies on monsoon rain while 40 percent is carried out through irrigation. Agriculture is a major contributor to the country's GDP. (Photo by Narendra Shrestha/EPA/EFE)

People, carry food and water, past a tractor stuck in mud, stones and debris that were piled in a flood in the mountain village of Sipkovica, just above the town of Tetovo, in northwestern Macedonia, on Tuesday, August 4, 2015. A small number of people including children have died in floods that erupted after an hour of heavy torrential rains and strong winds that hit Tetovo and northwestern region of Macedonia late on Monday. (Photo by Zoran Andonov/AP Photo)

Fishermen move a fishing boat to a safer place along the shore ahead of cyclone Hudhud at Ganjam district in Odisha October 11, 2014. The India Meteorological Department described Cyclone Hudhud as a “very severe” storm that could pack winds of 195 kilometers (120 miles) per hour and cause torrential rains when it makes landfall near the port city of Visakhapatnam around noon Sunday. (Photo by Reuters/Stringer)

A woman is assisted while crossing a flooded street after the Huayco river overflooded its banks sending torrents of mud and water rushing through the streets, in Huachipa, Peru on March 17, 2017. Muddy water spilled onto streets and into homes on Thursday in a new round of unusually heavy rains that has killed at least a dozen people in Peru and now threatens flooding in the capital. (Photo by Guadalupe Pardo/Reuters)