A red-tailed sportive lemur sleeps in side a tree trunk at the Kirindy forest reserve near the city of Morondava, Madagascar, September 1, 2019.Picture taken September 1, 2019. REUTERS/Baz Ratner

A grey mouse lemur is seen at the Kirindy forest near the city of Morondava, Madagascar, August 30, 2019.Picture taken August 30, 2019. REUTERS/Baz Ratner

General view of Nevada Copper's Pumpkin Hollow copper mine in Yerington, Nevada, U.S., January 10, 2019. Picture taken January 10, 2019. REUTERS/Bob Strong

General view of Yerington located near the Nevada Copper's Pumpkin Hollow copper mine, Nevada, U.S., January 10, 2019. Picture taken January 10, 2019. REUTERS/Bob Strong

General view of Nevada Copper's Pumpkin Hollow copper mine in Yerington, Nevada, U.S., January 10, 2019. Picture taken January 10, 2019. REUTERS/Bob Strong

Nevada Copper's Pumpkin Hollow copper mine in Yerington, Nevada, U.S., January 10, 2019. Picture taken January 10, 2019. REUTERS/Bob Strong

The hoist operator monitors screens at Nevada Copper's Pumpkin Hollow copper mine in Yerington, Nevada, U.S., January 10, 2019. Picture taken January 10, 2019. REUTERS/Bob Strong

David Swisher, Vice President of Operations at Nevada Copper's Pumpkin Hollow copper mine, points to images which monitor mine activity in Yerington, Nevada, U.S., January 10, 2019. Picture taken January 10, 2019. REUTERS/Bob Strong

A monitor shows mine activity at Nevada Copper's Pumpkin Hollow copper mine in Yerington, Nevada, U.S., January 10, 2019. Picture taken January 10, 2019. REUTERS/Bob Strong

General view of Nevada Copper's Pumpkin Hollow copper mine in Yerington, Nevada, U.S., January 10, 2019. Picture taken January 10, 2019. REUTERS/Bob Strong

General view of Nevada Copper's Pumpkin Hollow copper mine in Yerington, Nevada, U.S., January 10, 2019. Picture taken January 10, 2019. REUTERS/Bob Strong

General view of Nevada Copper's Pumpkin Hollow copper mine in Yerington, Nevada, U.S., January 10, 2019. Picture taken January 10, 2019. REUTERS/Bob Strong

David Swisher, Vice President of Operations at Nevada Copper's Pumpkin Hollow copper mine, describes a piece of equipment in Yerington, Nevada, U.S., January 10, 2019. Picture taken January 10, 2019. REUTERS/Bob Strong

General view of Nevada Copper's Pumpkin Hollow copper mine in Yerington, Nevada, U.S., January 10, 2019. Picture taken January 10, 2019. REUTERS/Bob Strong

David Swisher, Vice President of Operations at Nevada Copper's Pumpkin Hollow copper mine, holds a piece of ore taken from the mine in Yerington, Nevada, U.S., January 10, 2019. Picture taken January 10, 2019. REUTERS/Bob Strong

General view of Nevada Copper's Pumpkin Hollow copper mine in Yerington, Nevada, U.S., January 10, 2019. Picture taken January 10, 2019. REUTERS/Bob Strong

A man dressed up as a character from the movie "Sleepy Hollow" takes part with his horse in the "Noche del Terror" (Horror night) during Halloween celebrations in the neighborhood of Churriana, near Malaga, southern Spain, November 2, 2018. REUTERS/Jon Nazca

A pumpkin is seen along the route as people take part in a procession up the hill of Tlachtga as part of the Flame of Samhain festival, in Athboy, Ireland, October 31, 2018. Samhain is believed to be the ancient precursor to Halloween and marks the end of the old Celtic year and the beginning of the new year where the spirits of the dead are passed onto the next world. REUTERS/Clodagh Kilcoyne

A view of the hollow fibre membrane used in the microfiltration process at a NEWater plant in Singapore July 19, 2018. Picture taken July 19, 2018. REUTERS/Edgar Su

A dairy farm is seen during a tour by U.S. Agriculture Secretary Sonny Perdue at Dutch Hollow farm in Schodack Landing, New York, U.S., August 23, 2018. Picture taken August 23, 2018. REUTERS/Shannon Stapleton

Dairy farmers participate in a listening session during a tour by U.S. Agriculture Secretary Sonny Perdue at Dutch Hollow farm in Schodack Landing, New York, U.S., August 23, 2018. Picture taken August 23, 2018. REUTERS/Shannon Stapleton

A gun owner displays 10 mm Auto cartridges with Barnes TAC-XP hollow point bullets in Vienna, Austria, March 22, 2018. REUTERS/Heinz-Peter Bader

A gun owner displays 10 mm Auto cartridges with Barnes TAC-XP hollow point bullets in Vienna, Austria, March 22, 2018. REUTERS/Heinz-Peter Bader

A squirrel carries litter to its hollow in Gorky park after a heavy snowfall in Minsk, Belarus December 10, 2017. REUTERS/Vasily Fedosenko

A squirrel feeds in a tree hollow in Gorky park after a heavy snowfall in Minsk, Belarus December 10, 2017. REUTERS/Vasily Fedosenko

Members of the Iraqi Counter Terrorism Service (CTS) forces look at the positions of Islamic State militants during clashes in western Mosul, Iraq, May 15, 2017. Danish Siddiqui: "In May, I was accompanying a senior commander of Counter Terrorism Service, an elite Iraqi security force trained by the U.S., during the battle to take control of Western Mosul. We arrived at a small house on the frontline after walking through holes in the walls between homes. Islamic State snipers were firing a few hundred meters away. The people who once lived there departed quickly, leaving clothes and toys scattered across the floor. The next inhabitants left hollow shell casings. The CTS had taken over the house a day ago. The curtain was a bed sheet. They stood behind it to identify enemy snipers and watch one of their own. It's a quiet picture that tells of even the most uneventful of moments on the front, when nothing may happen, and everything is possible." REUTERS/Danish Siddiqui/File photo SEARCH "POY IS" FOR THIS STORY. SEARCH "REUTERS POY" FOR ALL BEST OF 2017 PACKAGES. TPX IMAGES OF THE DAY

A tightening siege has pushed people to the verge of famine in the eastern suburbs of Damascus, residents and aid workers say, bringing desperation to the only major rebel enclave near the Syrian capital. At two and a half years old, Hala al-Nufi weighs less than five kilos (12 pounds). She suffers from a metabolic disorder, but a lack of adequate food has made the case extreme. Hala, her eyes hollow and her translucent skin stretching over her tiny bones, had gotten sicker in recent months, her parents said. They worry she will not survive the siege. REUTERS/Bassam Khabieh SEARCH "KHABIEH MALNUTRITION" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. TPX IMAGES OF THE DAY. Matching text: MIDEAST-CRISIS/SYRIA-GHOUTA

A 33 mm KMB Ladg 95 hollow charge for the clearing of unexploded ordnance is displayed at the Waffenplatz Zuerich-Reppischtal base of the Swiss Army in Birmensdorf, Switzerland January 19, 2017. REUTERS/Arnd Wiegmann

John Hollow of Helena, MT, helps move food supplies out of the path of potential spring floods at the Dakota Access Pipeline protest camp near Cannon Ball, North Dakota, U.S., January 24, 2017. REUTERS/Terray Sylvester

John Hollow of Helena, MT, helps move food supplies out of the path of potential spring floods at the Dakota Access Pipeline protest camp near Cannon Ball, North Dakota, U.S., January 24, 2017. REUTERS/Terray Sylvester

A member of the Russian Marines, who are stationed onboard the anti-submarine vessel Admiral Tributs, uses a sledge hammer to break two hollow blocks on top of his comrade during a public demonstration of capabilities at Luneta National Park in Metro Manila, Philippines January 5, 2017. REUTERS/Romeo Ranoco

A dog named Darby leaps from the diving board to fetch a tennis ball at Sleep Hollow Bath and Racquet Club in Falls Church, Virginia September 11, 2016. REUTERS/Kevin Lamarque

A woodpecker looks out of a hollow in a tree in the 30 km (19 miles) exclusion zone around the Chernobyl nuclear reactor near the abandoned village of Babchin, Belarus, April 3, 2016. What happens to the environment when humans disappear? Thirty years after the Chernobyl nuclear disaster, booming populations of wolf, elk and other wildlife in the vast contaminated zone in Belarus and Ukraine provide a clue. On April 26, 1986, a botched test at the nuclear plant in Ukraine, then a Soviet republic, sent clouds of smouldering radioactive material across large swathes of Europe. Over 100,000 people had to abandon the area permanently, leaving native animals the sole occupants of a cross-border "exclusion zone" roughly the size of Luxembourg. REUTERS/Vasily Fedosenko SEARCH "WILD CHERNOBYL" FOR THIS STORY. SEARCH "THE WIDER IMAGE" FOR ALL STORIES

A voter receives a sticker from a polling station worker after he cast his ballot in the Super Tuesday election at Sleepy Hollow Elementary School in Falls Church, Virginia March 1, 2016.REUTERS/Kevin Lamarque

Voters depart after casting their ballots in the Super Tuesday election at Sleepy Hollow Elementary School in Falls Church, Virginia March 1, 2016. REUTERS/Kevin Lamarque

A voter receives his ballot in the Super Tuesday election at Sleepy Hollow Elementary School in Falls Church, Virginia March 1, 2016. REUTERS/Kevin Lamarque

Voters receive their ballot to vote in the Super Tuesday election at Sleepy Hollow Elementary School in Falls Church, Virginia March 1, 2016. REUTERS/Kevin Lamarque

A voter fills out his ballot in the Super Tuesday election at Sleepy Hollow Elementary School in Falls Church, Virginia March 1, 2016.REUTERS/Kevin Lamarque

Voters stand in line to receive their ballot to vote in the Super Tuesday election at Sleepy Hollow Elementary School in Falls Church, Virginia March 1, 2016.REUTERS/Kevin Lamarque

A voter fills out her ballot to vote in the Super Tuesday election at Sleepy Hollow Elementary School in Falls Church, Virginia March 1, 2016.REUTERS/Kevin Lamarque TPX IMAGES OF THE DAY

With her children Peter and Maria at her side, Eleni Karageorge votes in the Super Tuesday election at Sleepy Hollow Elementary School in Falls Church, Virginia March 1, 2016.REUTERS/Kevin Lamarque

Tori Kelly and James Bey perform "Hollow" at the 58th Grammy Awards in Los Angeles, California February 15, 2016. REUTERS/Mario Anzuoni

Tori Kelly and James Bey perform "Hollow" at the 58th Grammy Awards in Los Angeles, California February 15, 2016. REUTERS/Mario Anzuoni

Christmas lights are seen on a home in the Sleepy Hollow neighborhood of Torrance, California, United States, December 15, 2015. In many neighborhoods of Los Angeles, homeowners compete for the most lavish and creative holiday light displays. Torrance's Sleepy Hollow is one such neighborhood where every home outdoes the next: surfing Santas, life-size nativity scenes, ferris wheels, and giant inflatable snowmen line the lawns on every street. Picture taken December 15, 2015. REUTERS/Lucy Nicholson

Holiday lights are seen on a home in the Sleepy Hollow area of Torrance, California, United States, December 15, 2015. In many neighborhoods of Los Angeles, homeowners compete for the most lavish and creative holiday light displays. Torrance's Sleepy Hollow is one such neighborhood where every home outdoes the next: surfing Santas, life-size nativity scenes, ferris wheels, and giant inflatable snowmen line the lawns on every street. Picture taken December 15, 2015. REUTERS/Lucy Nicholson

Holiday lights are seen on a home in the Sleepy Hollow neighborhood of Torrance, California, United States, December 15, 2015. In many neighborhoods of Los Angeles, homeowners compete for the most lavish and creative holiday light displays. Torrance's Sleepy Hollow is one such neighborhood where every home outdoes the next: surfing Santas, life-size nativity scenes, ferris wheels, and giant inflatable snowmen line the lawns on every street. Picture taken December 15, 2015. REUTERS/Lucy Nicholson

Christmas lights are seen on a home in the Sleepy Hollow neighborhood of Torrance, California, United States, December 15, 2015. In many neighborhoods of Los Angeles, homeowners compete for the most lavish and creative holiday light displays. Torrance's Sleepy Hollow is one such neighborhood where every home outdoes the next: surfing Santas, life-size nativity scenes, ferris wheels, and giant inflatable snowmen line the lawns on every street. Picture taken December 15, 2015. REUTERS/Lucy Nicholson

Holiday lights are seen on a home in the Sleepy Hollow area of Torrance, California, United States, December 15, 2015. In many neighborhoods of Los Angeles, homeowners compete for the most lavish and creative holiday light displays. Torrance's Sleepy Hollow is one such neighborhood where every home outdoes the next: surfing Santas, life-size nativity scenes, ferris wheels, and giant inflatable snowmen line the lawns on every street. Picture taken December 15, 2015. REUTERS/Lucy Nicholson

Christmas lights are seen on a home in the Sleepy Hollow area of Torrance, California, United States, December 15, 2015. In many neighborhoods of Los Angeles, homeowners compete for the most lavish and creative holiday light displays. Torrance's Sleepy Hollow is one such neighborhood where every home outdoes the next: surfing Santas, life-size nativity scenes, ferris wheels, and giant inflatable snowmen line the lawns on every street. Picture taken December 15, 2015. REUTERS/Lucy Nicholson

Christmas lights are seen on a home in the Sleepy Hollow neighborhood of Torrance, California, United States, December 15, 2015. In many neighborhoods of Los Angeles, homeowners compete for the most lavish and creative holiday light displays. Torrance's Sleepy Hollow is one such neighborhood where every home outdoes the next: surfing Santas, life-size nativity scenes, ferris wheels, and giant inflatable snowmen line the lawns on every street. Picture taken December 15, 2015. REUTERS/Lucy Nicholson

A Christmas nativity scene is seen outside a home in the Sleepy Hollow area of Torrance, California, United States, December 15, 2015. In many neighborhoods of Los Angeles, homeowners compete for the most lavish and creative holiday light displays. Torrance's Sleepy Hollow is one such neighborhood where every home outdoes the next: surfing Santas, life-size nativity scenes, ferris wheels, and giant inflatable snowmen line the lawns on every street. Picture taken December 15, 2015. REUTERS/Lucy Nicholson

Holiday lights are seen on a home in the Sleepy Hollow area of Torrance, California, United States, December 15, 2015. In many neighborhoods of Los Angeles, homeowners compete for the most lavish and creative holiday light displays. Torrance's Sleepy Hollow is one such neighborhood where every home outdoes the next: surfing Santas, life-size nativity scenes, ferris wheels, and giant inflatable snowmen line the lawns on every street. Picture taken December 15, 2015. REUTERS/Lucy Nicholson

Christmas lights are seen on a home in the Sleepy Hollow area of Torrance, California, United States, December 15, 2015. In many neighborhoods of Los Angeles, homeowners compete for the most lavish and creative holiday light displays. Torrance's Sleepy Hollow is one such neighborhood where every home outdoes the next: surfing Santas, life-size nativity scenes, ferris wheels, and giant inflatable snowmen line the lawns on every street. Picture taken December 15, 2015. REUTERS/Lucy Nicholson

Christmas lights are seen on a home in Torrance, California, United States, December 15, 2015. In many neighborhoods of Los Angeles, homeowners compete for the most lavish and creative holiday light displays. Torrance's Sleepy Hollow is one such neighborhood where every home outdoes the next: surfing Santas, life-size nativity scenes, ferris wheels, and giant inflatable snowmen line the lawns on every street. Picture taken December 15, 2015. REUTERS/Lucy Nicholson

Christmas lights are seen on a home in the Sleepy Hollow neighborhood of Torrance, California, United States, December 15, 2015. In many neighborhoods of Los Angeles, homeowners compete for the most lavish and creative holiday light displays. Torrance's Sleepy Hollow is one such neighborhood where every home outdoes the next: surfing Santas, life-size nativity scenes, ferris wheels, and giant inflatable snowmen line the lawns on every street. Picture taken December 15, 2015. REUTERS/Lucy Nicholson

Holiday lights are seen on a home in Torrance, California, United States, December 15, 2015. In many neighborhoods of Los Angeles, homeowners compete for the most lavish and creative holiday light displays. Torrance's Sleepy Hollow is one such neighborhood where every home outdoes the next: surfing Santas, life-size nativity scenes, ferris wheels, and giant inflatable snowmen line the lawns on every street. Picture taken December 15, 2015. REUTERS/Lucy Nicholson