Runners sleep before competing in the 2016 New York City Marathon in the Manhattan borough of New York City, NY, U.S. November 6, 2016. (Photo by Eduardo Munoz/Reuters)

A child sleeps inside a makeshift hammock made of a saree which is a tradition Indian costume worn by women, along a road in New Delhi on August 19, 2021. (Photo by Sajjad Hussain/AFP Photo)

Penny Verdin displays a sleeping squirrel she helped rescue after it was injured during Hurricane Ida, Saturday, September 4, 2021, in Dulac, La. (Photo by John Locher/AP Photo)

A novice Bhutanese monk sleeps after hours of prayer waiting for class to be over at the Dechen Phodrang monastery October 18, 2011 in Thimphu, Bhutan. The monks average about 10 hours of study a day waking up at 5:00am. (Photo by Paula Bronstein/Getty Images)

Dancers Amy Hadley and Bethany Kingsley-Garner from the Scottish Ballet wait backstage during the dress rehearsal of the current production of “Sleeping Beauty” at the Theatre Royal on December 16, 2011 in Glasgow, Scotland. (Photo by Jeff J Mitchell/Getty Images)

This watering hole is the social hub of the veldt; the scrubby grasslands that stretch across Namibia. The scorched earth supports sometimes fragile populations of magnificent wildlife – from endangered predators to plentiful herds of game. But these gentle giraffes and elephants need to be careful: lions don’t sleep at night, they hunt! The spectacular starscape above southern Africa is unchanged since explorers first mapped the continent. The photographer, Pietro Olivetta from Italy, said he had to be patient to capture these shots – but it was worth the wait. (Photo by Pietro Olivetta/Caters News)

13-year-old Emmanuel Festo from Tanzania poses for a portrait with a plush toy that he says makes him feel safe at night and that he sleeps with, in New York's Staten Island, September 21, 2015. Albino body parts are highly valued in witchcraft and can fetch a high price. Superstition leads many to believe albino children are ghosts who bring bad luck. Some believe the limbs are more potent if the victims scream during amputation, according to a 2013 United Nations report. (Photo by Carlo Allegri/Reuters)

“Himalayan Dog”. This dog just appeared out of nowhere and followed us for an entire week during our trekking trip in the Himalayan outback. He always used to sleep in front of our tent and guarded us in the nights. When I decided to get up at 4 a.m. to climb the next 5000 m peak for sunrise he accompanied me as well. On the top he was sitting for the entire 30 minutes on this place looking straight into the countryside. Photo location: Ladakh, India. (Photo and caption by Sebastian Wahlhuetter/National Geographic Photo Contest)