“The Challenge!” Young boy relishes in a game of tug of war before school. Photo location: Lake Titicaca, Peru. (Photo and caption by Paul Heyman/National Geographic Photo Contest)

A sales woman of a fish shop shows king crabs to a customer and negotiates the price in Noryangjin Fish Market is seen on August 1, 2015 in Seoul, South Korea. Noryangjin Fish Market was established in 1927 as Gyeongseong Susan in Jung-gu near Seoul Station and moved to its current location in 1971. (Photo by Shin Woong-jae/The Washington Post)

School children dressed in traditional attire eat breakfast before participating in a Republic day parade in Bangalore, India, Thursday, January 26, 2017. (Photo by Aijaz Rahi/AP Photo)

A girl plays with coloured chicks for sale prior to Easter celebrations in Byblos, Lebanon on March 22, 2015. (Photo by Jamal Saidi/Reuters)

A girl with Russian national flags painted on her cheeks takes part in celebrations marking the first anniversary of Russia's annexation of Crimea, in central Simferopol March 16, 2015. Russia marks one year anniversary of annexation of Ukraine's Crimea peninsula this week. (Photo by Maxim Shemetov/Reuters)

As cheap Chinese-made motorbikes flood Pakistan’s roads, fans of vintage Vespa scooters are scrambling to find spare parts and preserve models that hark back to a bygone era. Here: A restored Vespa scooter painted in Pakistani truck art style, is parked alongside traditionally-coloured scooters at a Vespa restoration and repair workshop in Islamabad, Pakistan February 27, 2018. (Photo by Caren Firouz/Reuters)

A man walks by as tourists take selfies on the French Riviera city of Nice on June 24, 2019, as temperatures soar to 33 degrees Celsius. Forecasters say Europeans will feel sizzling heat this week with temperatures soaring as high as 40 degrees Celsius (104 degrees Fahrenheit) in an “unprecedented” June heatwave hitting much of Western Europe. (Photo by Valery Hache/AFP Photo)

A Syrian boy plays with the head of a sacrificed sheep at a DIP camp for Interally Displaced Persons near the town of Aqrabat in Syria's northern Idlib province on August 12, 2019. Known as the “big” festival, Eid Al-Adha is celebrated each year by Muslims sacrificing various animals according to religious traditions, including cows, camels, goats and sheep. The festival marks the end of the Hajj pilgrimage to Mecca and commemorates Prophet Abraham's readiness to sacrifice his son to show obedience to God. (Photo by Aaref Watad/AFP Photo)