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)

An Indian white tiger cools off in a pond in its enclosure at Chhat Bir Zoo on the outskirts of Chandigarh on May 22, 2016. Temperatures have soared to a scorching 51 degrees Celsius in one Indian city, meteorologists said, with the ferocious heat setting a new national record. Northern Phalodi wilted as the mercury reached a new high on May 20, equivalent to 123.8 Fahrenheit, beating a 60-year-old record. (Photo by Shammi Mehra/AFP Photo)

Actress Bella Thorne attends the Teen Choice Awards 2015 at the USC Galen Center on August 16, 2015 in Los Angeles, California. (Photo by Steve Granitz/WireImage)

In this May 3, 2016 photo provided by the New York State Department of Environmental Conservation, a deer with its head caught in the globe from a lighting fixture over its head stands in the woods in Centereach, N.Y. The deer was able to extricate itself with the help of Environmental Conservation Officer, Jeff Hull. Hull wrestled with the deer for a while and the globe shook free in the process. (Photo by New York State Department of Environmental Conservation via AP Photo)

Mayon Volcano spews ash and lava in the town of Daraga, Albay province, Philippines, 25 January 2018. Mayon volcano located in eastern Philippines and active over the last 10 days spewed fresh lava and ash while the number of evacuees exceeded 60 thousand in the face of the threat of an even more potent explosion. The Philippines, which currently has 23 active volcanoes, is situated on the so-called 'Pacific Ring of Fire', an area known for its intense seismic activity which extends from the west coast of the American continent to New Zealand, Japan, the Philippines and Indonesia. (Photo by Francis R. Malasig/EPA/EFE)

Mary McHugh mourns her slain fiance Sgt. James Regan at “Section 60” of the Arlington National Cemetery May 27, 2007. Regan, a US Army Ranger, was killed by an IED explosion in Iraq. (Photo by John Moore/Getty Images)

Performers of circus company Circa perform during a photocall for the Edinburgh Festival Fringe on Calton Hill on August 1, 2017 in Edinburgh, United Kingdom. (Photo by Murdo MacLeod/The Guardian)

Courtney Stodden attends the finale of “Celebs Go Dating” TV show filming at Dirty Martini in London, England on July 26, 2017. (Photo by Beretta/Sims/Rex Features/Shutterstock)