This 1950s photo provided by the Estate of Vivian Maier and John Maloof Collection shows Maier in a self-portrait as she looks into a storefront wearing a hat in New York. New research about Maier shows the enigmatic Chicago nanny was obsessive about honing her skills as a photographer starting in 1950. (Photo by Vivian Maier/Estate of Vivian Maier and John Maloof Collection via AP Photo)

Igor Armicach, a doctoral student at Hebrew University's Arachnid Collection, looks onto giant spider webs, spun by long-jawed spiders (Tetragnatha), covering sections of the vegetation along the Soreq creek bank, near Jerusalem, Israel on November 7, 2017. (Photo by Ronen Zvulun/Reuters)

A woman wearing a scarf to cover her face looks on as she waits for a passenger bus on a smoggy morning in New Delhi, India, November 8, 2017. The Great Smog of Delhi is an ongoing severe air-pollution event in New Delhi and adjoining areas in the National Capital Territory of India, in November 2017. Air pollution at this time peaked on both PM 2.5 and PM 10 levels. It has been reported as one of the worst levels of air quality in Delhi since 1999. (Photo by Saumya Khandelwal/Reuters)

A female hippopotamus named “Mali”, which means Jasmine, eats fruits arranged to look like a cake during her 50th birthday celebration at Dusit Zoo in Bangkok, Thailand September 23, 2016. (Photo by Chaiwat Subprasom/Reuters)

Visitors look at an artwork “Hierarchy of Prosperity” created by Indonesian artist Eko Nugroho during the VIP preview of the art fair “Art Basel” in Hong Kong, Tuesday, March 22, 2016. A set of gold-plated metal cubes, tapestries embroidered by unknown North Korean artisans and bales of cardboard waste are among the highlights of the Art Basel Hong Kong fair opening this week. (Photo by Kin Cheung/AP Photo)

People look at sharks from an underwater room structure installed in the Aquarium of Paris, France, March 14, 2016. Airbnb and the Aquarium of Paris offer contest winners a night underwater sleeping with sharks and create a research platform for “misunderstood” shark species. (Photo by Charles Platiau/Reuters)

Iraqi Kurdish female fighter Haseba Nauzad looks through a pair of binoculars during a deployment near the frontline of the fight against Islamic State militants in Nawaran near Mosul, Iraq, April 20, 2016. (Photo by Ahmed Jadallah/Reuters)

Malena, 7, looks at Belgian clown Lili Bellule at the pediatric department of the Hopital Erasme at the Universite Libre de Bruxelles (ULB), in Brussels January 27, 2015. The hospital offers performances by musicians and clowns as a form of therapy to help children cope with dealing with the stress and fear caused by hospitalization. (Photo by Yves Herman/Reuters)