The cassowary has been called the world's most dangerous bird after it killed a man in Florida last year. Its lethal weapon is its long dagger-like middle toes.

But for scientists and animal enthusiasts, what's intriguing about the large flightless bird is its extraordinary look, particularly its feathers. Although it doesn't necessarily have the 'wow factor' like that of a peacock, its blue, turquoise, and magenta colors still look magnificent to many. Some even call it the "high-fashion dinosaur."

Chad Eliason, a postdoctoral fellow and a staff scientist at the Field Museum in Chicago, says the birds measure a little over a meter tall, have dense bones, and are pretty heavy. He says the birds can undoubtedly cause some severe damage.

Eliason and his co-author Julia Clarke published a new study on the giant flightless bird on May 13, in the journal Science Advances.

In the study, the authors suggested that the cassowary's distinct glossy characteristic would have evolved progressively over time. They have observed this with an ancestral bird losing its barbules and the flightless bird developing into having a thicker central feather shaft.

Eliason believes that the bird's flightlessness might have given them more room to develop their oddly-shaped feathers. He added that the need for flying is a substantial force on determining a bird's wing shape. Since cassowaries don't fly, it might have resulted in new feather morphologies that gave the bird's feathers their gloss.

Watch Out, This Bird Can Kick and Kill

The cassowary isn't the only bird with lethal legs and claws. Another flightless bird that falls under the 'lethal' category is the ostrich. Eliason says that with all the stories about dangerous kicks and their sharp claws, this would make you think that the birds might genuinely be related to dinosaurs.

The staff from San Diego Zoo say that each of the cassowary's three-toed feet has a claw reaching up to 4 inches long, allowing it to slice open a predator with a single kick. They add that it can also run up to 31 miles per hour and jump up to seven feet.

The cassowary made headlines last year when a man in Florida, a caretaker of the species, was killed by the bird after accidentally falling into its housing pen. 75-year-old Marvin Hajos, initially made a call to 911 after he fell in, but unfortunately was too late as the cassowary already attacked him repeatedly, which caused his death.

More than Just Pretty Feathers

The new study on the bird's feathers taken from a dead bird has now shown what gives cassowary feathers their glossy black shine.

Not like other shiny birds, like crows or hummingbirds, the cassowary's glossiness is produced by the rachis, or the feather's spine, rather than the barbules, or the delicate filament fringes of a feather.

Because the soft barbules on cassowary feathers are few and scattered, the rachis gets more exposure to light compared to birds with thick feathers, which gives it a chance to really shine.