Thousands of species of amphibians are endangered and hundreds have already disappeared, but in recent years, a team of scientists and conservationists have re-discovered some of these “lost” species and uncovered previously unknown varieties. Here: Miniature glass frog. (Photo by Robin Moore)

A helicopter drops water over a wildfire as a firefighter works to contain it in Benahavis, southern Spain, May 19, 2015. (Photo by Jon Nazca/Reuters)

Residents cross over an improvised bridge after a landslide sent mud and water crashing onto homes close to the municipality of Salgar in Antioquia department, Colombia May 19, 2015. A landslide sent mud and water crashing onto homes in a town in Colombia's northwest mountains on Monday, killing at least 50 people and injuring dozens, officials said. (Photo by Jose Miguel Gomez/Reuters)

Four-month-old fox cubs squaring up to each other in Walthamstow, England on August 7, 2015. (Photo by Greg Morgan/Barcroft Media)

Women dance in costume during the West Indian Day Parade in Brooklyn, New York September 7, 2015. The parade, which takes place annually, celebrates Caribbean culture and history. (Photo by Andrew Kelly/Reuters)

The "Skylanders Eruptor" balloon moves by people on balconies during the 89th Macy's Thanksgiving Day Parade in the Manhattan borough of New York, November 26, 2015. (Photo by Andrew Kelly/Reuters)

At Studio 54, an unidentified trio of two woman and one man recline on a banquette, miming unconsciousness, New York, New York, September 29, 1977. (Photo by Allan Tannenbaum/Getty Images)

Hugh Hefner spanks playboy models Izabella Kasprzyk and Bridget Marquardt during their birthday dinner party at Joya restaurant on September 25, 2002 in Beverly Hills, California. Playboy founder and sеxual revolution symbol Hugh Hefner has died at age 91. The magazine released a statement saying Hefner died at his home in Los Angeles of natural causes on Wednesday night, September 27, 2017, surrounded by family. (Photo by David Klein/Getty Images)