May 8, 2026 at 11:35 pm

They’re Six Feet Tall, Run Fifty Kilometres Per Hour, And Possess Five-Inch, Razor-Sharp Claws – But There Is Still So Much To Love About The World’s Most Dangerous Bird

by Kyra Piperides

A close-up of a cassowary

Pexels

If you’ve ever wished you could walk amongst dinosaurs (wait – why would you wish this? Have you not seen Jurassic Park?) then you need to look no further than the Southern Cassowary.

While all birds are actually dinosaurs of a sort – with the Natural History Museum explaining that modern birds are directly related to theropods, with 150-million-year-old bird-like fossils evidencing this – the Cassowary takes this even further.

I mean, just look at it.

Still living wild in northeastern Australia, southern Papua New Guinea and Indonesia, it’s no surprise that – at between four and six and a half feet tall, reaching running speeds of up to 50 km/h and possessing sharp, five-inch claws – the cassowary is the world’s most dangerous bird.

A cassowary between trees

Pexels

But even though they’re super scary, there’s still a lot to love about the cassowary – love from a distance, that is.

Because the southern cassowary is a majestic beast. They’re brightly colored, blue, red and black – and though they’re dangerous, they’re naturally quite shy, flightless birds, eating mostly fruit and some small vertebrates, as the BBC’s Wildlife Magazine explained.

Though they’re solitary creatures, when fruit is most available – usually in the summer and early autumn – southern cassowaries turn to reproduction.

Communicating through infrasonic booms to attract a mate, the cassowaries take part in a low-key mating ritual which, if successful, results in some truly magnificent eggs.

A green cassowary egg

American Museum of Natural History/R. Mickens

For southern cassowaries, it is the male bird that incubates the eggs and takes care of the chicks when they hatch; after laying a clutch of between three and five bright green eggs, the female leaves the nest. Why green? Well the color is an incredible adaptation, as Wildlife Magazine continued:

“The greenish colour of southern cassowary eggs comes from biliverdin, a common pigment found in bird eggshells. As cassowaries are ground-nesting birds, the green colour of their eggs is used for camouflage against the surrounding vegetation in tropical forests to protect the eggs from potential predators.”

When the chicks eventually hatch, they are adorable brown and cream bundles of prehistoric joy – growing from around five or six inches to their final height of up to six and a half feet within three or four years.

And at around five years of age, the cassowary – which can live up to around forty years – is ready to produce a nest of green eggs itself.

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Kyra Piperides, PhD | Contributing Science Writer

Dr. Kyra Piperides is a contributing writer for TwistedSifter, specializing in Science & Discovery. Holding a PhD in English with a dedicated focus on the intersections of science, politics, and literature, she brings over 12 years of professional writing and editorial expertise to her reporting.

Kyra possesses a highly authoritative background in academic publishing, having served as the editor of an academic journal for three years. She is also the published author of two books and numerous research-driven articles. At TwistedSifter, she leverages her rigorous academic background to translate complex scientific concepts, global tech innovations, and environmental breakthroughs into highly engaging, accessible narratives for a mainstream audience.

Based in the UK, Kyra is an avid backpacker who spends her free time immersing herself in different cultures across distant shores—a passion that brings a rich, global perspective to her writing about Earth and nature.

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