A girl lights a candle as she marks the anniversary of 2015 Nepal earthquake, at Boudhanath stupa in Kathmandu, Nepal April 25, 2017. (Photo by Navesh Chitrakar/Reuters)

The car driven by Scott Dixon, of New Zealand, goes over the top of Jay Howard, of England, in the first turn during the running of the Indianapolis 500 auto race at Indianapolis Motor Speedway, Sunday, May 28, 2017, in Indianapolis. (Photo by Marty Seppala/AP Photo)

Model Adriana Lima attends the 19th Annual amfAR New York Gala at Cipriani Wall Street on February 8, 2017 in New York City. (Photo by Splash News and Pictures)

Model Hailey Baldwin is seen walking in Soho on February 10, 2017 in New York City. (Photo by Splash News and Pictures)

US actress Vanessa Hudgens poses upon her arrival for the 25th annual Elton John AIDS Foundation's Academy Awards Viewing Party on February 26, 2017 in West Hollywood, California. (Photo by Tibrina Hobson/AFP Photo)

A one-horned rhino walks on the street of Sauraha, a tourism hub in southwest Nepal’s Chitwan district on July 10, 2018. (Photo by Sunil Sharma/Xinhua News Agency/Alamy Stock Photo)

A girl dressed up as a emissary of the Three Wise Men poses for a photo as she waits for their arrival in a helicopter to take part in the traditional Epiphany parade in Ronda, Spain, January 5, 2018. (Photo by Jon Nazca/Reuters)

“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)