A Fulani Pastoralist carries two baby sheep on her donkey cart as her family move on northwards in Barkedji, Senegal on July 21, 2020. Thousands of Pastoralist families will start the movement north in the next weeks. With the first rains comes fresh grass and water for the Fulani herders' livestock, it also marks the point where most of the Pastoralist will move northwards until the dry season. (Photo by John Wessels/AFP Photo)

Riot police face off with demonstrators at the “Occupy Denver” camp on October 29, 2011 in Denver, Colorado. Following a march by protesters, police moved in on their encampment to tear down recently erected tents. They arrested numerous protesters, pepper-sprayed others and others reportedly fired rubber bullets at the crowd during the confrontation. (Photo by John Moore/Getty Images)

English pop singer Shane Fenton, later known as Alvin Stardust, autographing a woman's leg in his dressing room. (Photo by John Pratt/Keystone Features/Getty Images). September 1962

Recording artist Lady Gaga performs during a stop of The Monster Ball Tour at the MGM Grand Garden Arena March 25, 2011 in Las Vegas, Nevada. (Photo by Ethan Miller/Getty Images)

"La Montagna di Sale (The Salt Mountain)" by Mimmo Paladino is displayed in Piazza Duomo on April 5, 2011 in Milan, Italy.

Photographer and artist Jill Greenberg poses at her home to promote her Exhibit “Glass Ceiling: American Girl Doll” And Billboard For LA on September 29, 2011 in Los Angeles, California. (Photo by Frazer Harrison/Getty Images)

The photos were taken at the Piton de la Fournaise volcano on Reunion Island, a French island in the Indian Ocean one of the most active volcanoes in the world. Here: The powerful erupting volcano. (Photo by Luc Perrot/Caters News)

Ngorongoro Crater (Tanzania). At 610m deep and 260 sq km, this is the largest unflooded caldera in the world. A blue-green vision from above it's a haven for engangered wildlife and Maasai livestock. The crater was formed three million years ago when a giant volcano, which could have been as high as Kilimanjaro, exploded and collapsed. The caldera formed the concentric fractures in the crust cracked down to a magma reservoir deep underground. (Photo by John Bryant/Getty Images)