Four men ride a motorbike past sacrificial animals displayed for sale ahead of the Eid al-Adha festival at a livestock market in Sana'a, Yemen, 08 August 2019. Eid al-Adha is the holiest of the two Muslims holidays celebrated each year; it marks the yearly Muslim pilgrimage (Hajj) to visit Mecca, Islam's holiest place. Muslims slaughter a sacrificial animal and split the meat into three parts: one for family, one for friends and relatives, and one for the poor and needy. (Photo by Yahya Arhab/EPA/EFE)

In this October 24, 2010 file photo, Canadian-born actress Pamela Anderson poses for photographers during a photocall to unveil a new advertisement in aid of People for the Ethical Treatment of Animals (PETA) in London to encourage people to go vegetarian. PETA turns 35 years old in 2015, is the largest animal rights group in world with 3 million members, and has done a lot with a little s*x, shock and celebrity. (Photo by Akira Suemori/AP Photo)

A man rides through the flames on a horse during the “Luminarias” annual religious celebration on the eve of Saint Anthony's Day in the village of Alosno, southwest Spain, January 16, 2015. According to a tradition that dates back 500 years, people ride their horses through the narrow cobblestone streets of this small village to purify the animals with the smoke of the bonfires. Saint Anthony is the patron of animals. (Photo by Marcelo del Pozo/Reuters)

The contest began in 2007, and since then photographers from more than 70 countries have entered. Photo: Michael O'Neal of San Francisco won first place in the animals category in the 2014 iPhone Photography Awards. (Photo by Michael O'Neal)

A camel herder removes the rope from the mouth of a camel at the Pushkar Fair in Rajasthan, India, November 22, 2015. Thousands of animals, mainly camels, are brought to the annual fair to be traded. (Photo by Jitendra Prakash/Reuters)

An Andalusian horsewoman waits for the animal to drink water before a classical dressage contest during the Sacab Andalusian Horse Show in Coin, southern Spain, April 12, 2015. (Photo by Jon Nazca/Reuters)

An animal rights protester demonstrates for the abolition of bull runs and bullfights, three days before the start of the famous running of the bulls San Fermin festival in Pamplona, northern Spain, July 4, 2015. (Photo by Eloy Alonso/Reuters)

An iguana in Bali helped Julij Kopilović, age eight, from Slovenia, earn second runner-up in Amazing Animals. (Photo by Julij Kopilović/National Geographic)