Two Inuit children at Point Barrow, Alaska, holding the tusks of a large walrus, probably killed for food, circa 1930. (Photo by General Photographic Agency/Getty Images)

Pope Francis attends a circus performance during his weekly general audience at Paul VI hall on December 22, 2016 at the Vatican. (Photo by Alberto Pizzoli/AFP Photo)

General view of the entrance to the Swarowski Crystal World museum on its reopening day following renovation, in the western Austrian village of Wattens April 30, 2015. (Photo by Dominic Ebenbichler/Reuters)

A general view of atmosphere seen at Warner Bros. Premiere of "Entourage" held at Regency Village Theatre on Monday, June 1, 2015, in Westwood, Calif. (Photo by Eric Charbonneau/Invision for Warner Bros./AP Images

Cocoa Beach, Florida, USA. 7th October, 2016. Kaleigh Black, 14, left, and Amber Olsen, 12, run for cover as a squall with rain and wind pelt them while they explore the Cocoa Beach Pier on Friday (10/7/16) after hurricane Matthew passed to the east on Florida's east coast.(Photo by Douglas R. Clifford/Tampa Bay Times/ZUMA Wire/Alamy Live News)

This image made available by the Johns Hopkins University Applied Physics Laboratory on Wednesday, May 31, 2017 depicts NASA's Solar Probe Plus spacecraft approaching the sun. On Wednesday, NASA announced it will launch the probe in summer 2018 to explore the solar atmosphere. It will be subjected to brutal heat and radiation like no other man-made structure before. (Photo by Johns Hopkins University Applied Physics Laboratory via AP Photo)

New exhibition of sustainable fashion explores the role of tartan in Scottish traditional dance, opening on April 23, 2024 as part of the Pomegranates festival in Edinburgh, Scotland. Vengefully Changed Allegiance is asolo exhibition by fashion designer Alison Harm, founder of Edinburgh Psychomoda clothing brand, who uses industry scraps, vintage clot and broken jewellery. (Photo by Sally Anderson/Alamy Live News)