Samburu tribesmen stand during the Maralal Camel Derby, Kenya, August 15, 2015. Maralal, a small, arid town about an eight-hour drive north of the Kenyan capital Nairobi, holds an annual camel festival, bringing together members of the Samburu, Turkana and Pokot semi-nomadic cattle-herding tribes. (Photo by Goran Tomasevic/Reuters)

Men carry others, so they do not soil their shoes and clothes, through a mudslide caused by Tropical Storm Erika in Carries, Haiti, August 29, 2015. Erika, a tropical storm that killed 20 people on the Caribbean island of Dominica and at least one person in Haiti, fell apart on Saturday over eastern Cuba, the U.S. National Hurricane Center said. (Photo by Andres Martinez Casares/Reuters)

A vendor drinks water as she waits for customers at a roadside flower market in Ahmedabad, India, February 8, 2017. (Photo by Amit Dave/Reuters)

A cowgirl participates in the barrel race competition at the Bill Pickett Invitational Rodeo on April 1, 2017 in Memphis, Tennessee. The Bill Pickett Rodeo is the nations only touring black rodeo competition. The rodeo celebrates western heritage and the contributions that black cowboys and cowgirls have made to the sport of rodeo. (Photo by Scott Olson/Getty Images)

Riot police officers in position to crack down on demonstrators during a protest against Venezuelan President Nicolas Maduro, in Caracas on April 20, 2017. Venezuelan riot police fired tear gas Thursday at groups of protesters seeking to oust President Nicolas Maduro, who have vowed new mass marches after a day of deadly unrest. Police in western Caracas broke up scores of opposition protesters trying to join a larger march, though there was no immediate repeat of Wednesday's violent clashes, which left three people dead. (Photo by Juan Barreto/AFP Photo)

An Indian villager tries to tame a bull during a traditional bull-taming festival called “Jallikattu”, in the village of Palamedu, near Madurai, Tamil Nadu state, India, Monday, January 15, 2018. Jallikattu involves releasing a bull into a crowd of people who attempt to grab it and ride it. (Photo by R. Parthibhan/AP Photo)

Student Rabindra Bharati University celebrates the Holi festival, Color Festival on February 26, 2018 in Kolkata, India. Holi, the popular Hindu spring festival of colours is observed in India at the end of the winter season on the last full moon of the lunar month, and will be celebrated on March 1 this year. (Photo by Debajyoti Chakraborty/NurPhoto via Getty Images)

Artists perform during the opening show directed by German director Volker Hesse, on the opening day of the Gotthard rail tunnel, at the fairground Rynaecht at the northern portal in Erstfeld, Switzerland, Wednesday, June 1, 2016. The construction of the 57 kilometer long tunnel began in 1999, the breakthrough was in 2010. After the official opening on June 1, the commercial operation will start in December 2016. (Photo by Ruben Sprich\Pool Photo via AP Photo)