Bikini-clad women ski as they are led by a car during a performance on the frozen Yenisei River outside Krasnoyarsk, Siberia, Russia, March 20, 2016. The performance, entitled “Siberian Spring's Strings” and created with the participation of artist Vasily Slonov, marked the day of spring equinox (vernal equinox), according to organizers. (Photo by Ilya Naymushin/Reuters)

A Sikh warrior, wearing a huge turban attends the annual fair of “Hola Mohalla” in Anandpur Sahib, in the northern Indian state of Punjab, Monday, March 17, 2014. Believers from various parts of northern India collect at the religious fair to celebrate the festival of Holi in a tradition set by the tenth Sikh guru Guru Gobind Singh in the seventeenth century. Nihangs, or Sikh warriors, display their martial skills and attire during the fair, believed to be maintained in the exact tradition as set by the Guru. (Photo by Altaf Qadri/AP Photo)

A Hindu pilgrim feeds biscuits to an ox to seek blessing before heading for an annual trip to Sagar Island for the one-day festival of “Makar Sankranti”, in Kolkata, India January 10, 2017. (Photo by Rupak De Chowdhuri/Reuters)

A commuter exits a closed off station after a subway train derailment, Tuesday, June 27, 2017, in the Harlem neighborhood of New York. A subway train derailed near a station in Harlem on Tuesday, frightening passengers and resulting in a power outage as people were evacuated from trains along the subway line. The Fire Department of New York said a handful of people were treated for minor injuries at around 10 a.m. It said there was smoke but no fire. Delays were reported throughout the subway system. (Photo by Mary Altaffer/AP Photo)

“Originally published in the April 9, 1951, issue of LIFE magazine, W. Eugene Smith’s photo essay, «Spanish Village», has been lauded for more than six decades as the most moving photographic portrait ever made of daily life in rural Spain during the rule of dictator Francisco Franco”. – Time & Life Pictures. Photo: His wife, daughter, granddaughter and friends have their last earthly visit with a villager. (Photo by W. Eugene Smith/Time & Life Pictures)

Delphina Bianchi, 10, sits on the bed of a truck carrying giant pumpkins from her grandfather's John Muller's farm at the Annual Safeway World Championship Pumpkin Weigh-Off Monday, October 12, 2015, in Half Moon Bay, Calif. (Photo by Marcio Jose Sanchez/AP Photo)

This September 22, 2014 photo, shows a building with street art murals in the Santurce neighborhood in San Juan, Puerto Rico. (Photo by Ricardo Arduengo/AP Photo)

“Cassowaries are large, flightless birds related to emus and (more distantly) to ostriches, rheas, and kiwis”, writes Olivia Judson in the September issue of National Geographic magazine. How large? People-size: Adult males stand well over five foot five and top 110 pounds. Females are even taller, and can weigh more than 160 pounds. Dangerous when roused, they’re shy and peaceable when left alone. But even birds this big and tough are prey to habitat loss. The dense New Guinea and Australia rain forests where they live have dwindled. Today cassowaries might number 1,500 to 2,000. And because they help shape those same forests – by moving seeds from one place to another – “if they vanish”, Judson writes, “the structure of the forest would gradually change” too. (Photo by Christian Ziegler/National Geographic)