An upside-down pair of pants is seen atop a mound of snow, Wednesday, February 20, 2019, the result of yet another snow storm to hit Omaha, Neb. The latest winter storm dumped more snow on top of the existing snow, creating a problem of what to do with all the cleared snow. (Photo by Nati Harnik/AP Photo)

Saintsetseg Jambaldorj, a member of the Tsaatan ethnic minority, one of the last remaining groups of nomadic reindeer herders in East Taiga, Mongolia, wearing a traditional deel, on July 5, 2016. (Photo by Madoka Ikegami/Barcroft Images)

Li Yuming, a local farmer who is interested in scientific invention, works on his unfinished miniature submarine “Xiaguang V” on the outskirts of Wuhan, capital of central China's Hubei province August 24, 2007. “Xiaguang V”, which is 3-metre long, 1.2-metre in height, has a maximum diving depth of 20 metres, and can hold two adults and one child at the same time. The submarine will be used for tour after safety test, local media said. (Photo by Reuters/Stringer)

“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)

Ally Brooke, from left, Dinah-Jane Hansen, Camila Cabello, Lauren Jauregui and Normani Hamilton of Fifth Harmony, perform “Work From Home” at the Billboard Music Awards at the T-Mobile Arena on Sunday, May 22, 2016, in Las Vegas. (Photo by Chris Pizzello/Invision/AP Photo)

Lali carries balloons to sell on a beach in Mumbai, India, Sunday, October 11, 2015. The United Nations General Assembly marks October 11 as the International Day of the Girl Child, to recognize girls’ rights and the unique challenges girls face around the world. (Photo by Rafiq Maqbool/AP Photo)

A boy runs past one of the exhibits during the Dinosaurs exhibition in Belgrade, Serbia, Thursday, August 21, 2014. “Dino Park” has opened at Belgrade's Kalemegdan Fortress. (Photo by Darko Vojinovic/AP Photo)

A protester wearing a bra and with a message written on her chest can be seen during the first of hundreds of womens' marches organized around the world in a show of disapproval of U.S. President Donald Trump in Sydney, Australia, January 21, 2017. (Photo by Dan Himbrechts/Reuters/AAP)