“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)

A member of the Eton public school O.T.C. (Officers Training Corps) practising shouting out orders during a training session, 20th January 1940. (Photo by Hulton Archive/Getty Images)

Artwork by Ruth Bellotti & Steve Rosewell called “Soldier Scale 1:1” is seen at the 2008 Sculpture by the Sea launch at Mark's Park, Bondi on October 15, 2008 in Sydney, Australia. (Photo by Gaye Gerard/Getty Images)

Wai Ching Jason Poon of Hong Kong competes in the Men's 1m Springboard preliminary round during Day One of the 14th FINA World Championships at the Oriental Sports Center on July 16, 2011 in Shanghai, China. (Photo by Feng Li/Getty Images)

An injured woman is pictured near the Blue Parrot nightclub in Playa del Carmen, Quintana Ro state, Mexico where 5 people were killed, three of them foreigners, during a music festival on January 16, 2017. A shooting erupted at an electronic music festival in the Mexican resort of Playa del Carmen early Monday, leaving at least five people dead and sparking a stampede, the mayor said. Fifteen people were injured, some in the stampede, after at least one shooter opened fire before dawn at the Blue Parrot nightclub during the BPM festival. (Photo by Victor Vargas/AFP Photo)

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Fans dressed in Spider-Man outfits gather at a promotional event for the forthcoming “Spider-Man: Homecoming” movie at the Art Science Museum in Singapore on June 7, 2017. The movie will be shown in cinemas around the world from July 5 onwards. (Photo by Toh Ting Wei/AFP Photo)

Canada's Marissa Papaconstantinou makes her way to the finish line after falling in the Women's 200m T44 Final during day ten of the IPC World ParaAthletics Championships 2017 at London Stadium on July 23, 2017 in London, England. (Photo by Peter Cziborra/Reuters)