Mr. Zhong Hua, of Johns Hopkins University School of Medicine, took this image of the peripheral nerves (those outside of the brain) in an 11.5-day-old mouse embryo, magnified five times. (Photo by Zhong Hua)

This picture taken on January 6, 2018 shows macaque monkeys looking at a man's camera during snowfall at Wulongkou Nature Reserve in Jiyuan in China's central Henan province. (Photo by AFP Photo/China Stringer Network)

A couple covered in mud wait for it to dry at the Salt-works lakes near the Black Sea town of Burgas in Bulgaria on July 25, 2019. Thousands of tourists visit the red salt lakes for mud baths, which are believed to help the healing of muscular disorders and rheumatism. (Photo by Nikolay Doychinov/AFP Photo)

Selena Gomez, left, and Taylor Swift arrive at the MTV Video Music Awards at the Microsoft Theater on Sunday, August 30, 2015, in Los Angeles. (Photo by Jordan Strauss/Invision/AP Photo)

Singer Rihanna in the audience at the 54th Annual GRAMMY Awards held at Staples Center on February 12, 2012 in Los Angeles, California. (Photo by Larry Busacca/Getty Images For The Recording Academy)

Rita Ora attends the the GQ Men Of The Year Awards 2019 in association with HUGO BOSS at the Tate Modern on September 3, 2019 in London, England. (Photo by David M. Benett/Dave Benett/Getty Images for HUGO BOSS)

Recording artists Demi Lovato (L) and Iggy Azalea perform on the Pepsi Stage, during the 2015 MTV Video Music Awards, at The Orpheum Theatre on August 30, 2015 in Los Angeles, California. (Photo by Frederick M. Brown/Getty Images for MTV)

Model Kendall Jenner presents a creation during the 2016 Victoria's Secret Fashion Show at the Grand Palais in Paris, France, November 30, 2016. The pulse-quickening, celebrity-filled catwalk event of the year: the Victoria's Secret fashion show takes place in Paris with performances from Lady Gaga and Bruno Mars. (Photo by Charles Platiau/Reuters)