“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)

Vanessa Silva, 38, feeds macaws that fly to her apartment window every day looking for food, in Caracas, Venezuela, on November 24, 2014. A group of gold-and-royal blue birds poked their heads through Silva’s window, as if saying “I’m here, is anyone home?” “I’d seen them flying when I was down on the street, and I thought ‘Oh how pretty,’” the 38-year-old said, a macaw eating out of her hand. (Photo by Ariana Cubillos/AP Photo)

A Galapagos Tortoise shell is used as a foot rest at Heathrow Airport's Animal Reception Centre on January 25, 2011 in London, England. Many animals pass through the centre's doors ranging from exotic animals such as snow leopards and elephants, snakes and crocodiles, to the more common such as cats and dogs. In 2010 alone the centre processed approximately 10,500 cats and dogs, 1,300 birds, 105,000 day old chicks, 246,000 reptiles, 230 horses and 29 million fish. Most animals are part of zoo transfer schemes, the pet trade, or are pets in transit. (Photo by Dan Kitwood/Getty Images)

A bird vendor holds a cage with a bird on a sideroad after a heavy snowfall in Kabul on January 5, 2022. (Photo by Mohd Rasfan/AFP Photo)

Birds are seen at Kizilirmak Bird Paradise in Turkey's Samsun on April 22, 2021. Kizilirmak Delta Bird Sanctuary, which is on the UNESCO World Heritage Tentative List and hosts 359 to 487 species of birds in Turkey, became more active with the arrival of spring. (Photo by Mehmet Kumcagiz/Anadolu Agency via Getty Images)

A recently hatched baby Egret bird seen in a nest at the Gatorland Bird Rookery in Kissimmee, Florida on March 17, 2022. Gatorland is known as The Alligator Capital of the World and has a 10 acre natural bird rookery. (Photo by Ronen Tivony/SOPA Images/Rex Features/Shutterstock)

Katie Loynes of the Blues attempts to mark the ball during the AFLW Preliminary Final match between the Carlton Blues and the Fremantle Dockers at Ikon Park on March 23, 2019 in Melbourne, Australia. (Photo by Mike Owen/Getty Images)

The Blue Man Group performs on stage during a media preview ahead of their show in Singapore on March 31, 2016. Blue Man Group was started by three friends in New York in 1991 as a way to celebrate the human spirit through music, science, art and theater. (Photo by Roslan Rahman/AFP Photo)