Tyson the Bulldog sits with reindeer antlers on Christmas Day at Central Park in Manhattan, New York City, U.S., December 25, 2016. (Photo by Andrew Kelly/Reuters)

A model prepares backstage at the Meskita fashion show during Mercedes-Benz Fashion Week Spring 2015 on September 4, 2014 in New York City. (Photo by Larry Busacca/Getty Images for Meskita)

US MotoGP rider Nicky Hayden of the Aspar MotoGP team performs a wheelie during third free practice session for the motorcycle GP in Montmelo, Spain, Saturday, June 13, 2015. The Catalunya Grand Prix will take place on Sunday in Montmelo. (AP Photo/Manu Fernandez)

Tahiti, French Polynesia, June 5, 2016: Surfer Courtney Conlogue. ESPN The Magazine's The Body Issue set out seven years ago with one mission: to celebrate and explore the athletic form through powerful images and interviews. The cornerstone of each annual issue is The Bodies We Want photo portfolio, which features roughly 20 of the world's most elite athletes posing nude. (Photo by Steven Lippman for ESPN The Magazine Body Issue)

Baka pygmies in their forest home preparing food in, Sangha Forest, Central African Republic, February 2016. Here, in their forest home, traditional life continues in the face of multiplying challenges ranging from poachers, to ill health. Deep in the rainforests of central Africa lives one of the world’s most mysterious tribes. (Photo by Susan Schulman/Barcroft Images)

American soldiers with the 173rd Airborne Brigade Battle Company, on a battalion-wide mission in the Korengal Valley, looking for caves, weapons caches and known Taliban leaders, 2007. Tanner Stichter tends to Spc. Carl Vandeberge in the bushes moments after Vandeberge was shot in the stomach during a Taliban ambush, which killed one soldier and wounded two others. (Photo by Lynsey Addario)

In northwest Russia, in a small village called Alekhovshchina, Nadia Sablin's aunts spend the warmer months together in the family home and live as the family has always lived, chopping wood to heat the house and making their own clothes. Sablin's book of photographs, “Aunties: The Seven Summers of Alevtina and Ludmila”, is published by Duke University Press. Here: “Two-Handed Saw, 2014”. (Photo by Nadia Sablin)

People crowd onto 42nd Street as they take photos of the “Manhattanhenge” phenomenon in the Manhattan borough of New York July 11, 2014. Manhattanhenge, coined by astrophysicist Neil deGrasse Tyson, occurs twice a year, when the setting sun aligns itself with the east-west grid of streets in Manhattan. (Photo by Carlo Allegri/Reuters)