Dancers from the Philadelphia Ballet perform for Pope Francis (R) as he attends the Festival of Families rally in Philadelphia, Pennsylvania September 26, 2015. (Photo by Brian Snyder/Reuters)

A curious leopard cub toys with a camera at MalaMala Game Reserve in Mpumalanga Province, South Africa. (Photo by Barcroft Media)

In this July 10, 2014 photo, Chris Minore, of Orange, Conn., performs the under chop technique at the Adirondack Woodsmen's School at Paul Smith's College in Paul Smiths, N.Y. Eighteen young students in matching gray sports shirts took part recently in a weeklong crash course on old-school lumberjack skills such as sawing, chopping, ax throwing, log boom running and pole climbing. (Photo by Mike Groll/AP Photo)

A young Emirati boy looks on as his falcon flies at the Liwa desert, 220 kms west of Abu Dhabi, on the sidelines of the Mazayin Dhafra Camel Festival on December 21, 2013. The festival, which attracts participants from around the Gulf region, includes a camel beauty contest, a display of UAE handcrafts and other activities aimed at promoting the country's folklore. (Photo by Karim Sahib/AFP Photo)

Roped up climbers leave the summit of Breithorn at 4,164 metres (13,661 feet) on the ridge marking the border with Switzerland (left) and Italy in the Alpine resort of Zermatt August 4, 2014. Switzerland will vote on November 30 on an initiative from the group Ecopop which proposes a cap on the number of immigrants. The group says it is motivated by concerns about a lack of living space exerting too much pressure on the land and natural resources, rather than by opposition to foreigners. (Photo by Denis Balibouse/Reuters)

Qian Hao's imported Pekingese dog, Mixiu, runs in a park in Beijing, China, February 8, 2018. (Photo by Thomas Peter/Reuters)

Tip turkey, dumpster chook, rubbish raptor – the Australian white ibis goes by many unflattering names. But it is a true urban success story, scavenging to survive in cities across Australia as wetlands have been lost. Wildlife photographer Rick Stevens captured them in Sydney. Here: Of all the species affected by river regulation in Australia, the ibis is one of the few that has changed its behaviour and moved to coastal cities. (Photo by Rick Stevens/The Guardian)

Christian Balderosdasco, 31, is being pulled up a mud pit after diving for 3 hours to look for gold on March 22, 2017 in Paracale, Philippines. Apart from tunneling and sifting sand, locals dive down murky swamps with the aid of a compressor with air flowing in a small tube for breathing, as they blindly swim under the mud for up to four hours to look for tiny rocks containing gold particles. For decades, local residents at Paracale town work in hazardous conditions scavenging under the earth and diving into tunnels filled with mud using only makeshift tools to mine for gold, often placing their health and lives at risk. (Photo by Jes Aznar/Getty Images)