All birds are living dinosaurs, but the dagger-clawed cassowary especially looks the part. Here’s everything you need to know about the majestic—and terrifying—avians.

1. THE SOUTHERN CASSOWARY IS EARTH’S SECOND-HEAVIEST BIRD.

Scientists currently recognize three living species of cassowary—all of which are restricted to New Guinea, northeastern Australia, and nearby islands. Among them, the aptly-named dwarf cassowary is the smallest, with an average height of around 3 feet. Then there’s the northern cassowary, an orange-throated behemoth that can stand nearly 5 feet tall. But the southern cassowary is bigger than both: From toe to head-crest, this avian can stand 5 foot 6 inches tall. The only two birds that grow taller are ostriches and emus. Southern cassowaries do exceed the latter in weight, though; adults often tip the scales at 125 pounds. Behind ostriches, this makes them the second-heaviest birds on the planet.

2. THESE BIRDS HAVE DANGEROUS FEET.

In certain parts of their Australian range, you might come across warning signs that read “Be Cass-o-wary.” Heed this advice. Normally, cassowaries are shy, reclusive animals. But when threatened or cornered, they can become aggressive, striking back with powerful head-butts and pecks. The most dangerous weapon in their arsenal is a razor-sharp claw on the inner toe of each foot, which, in southern cassowaries, grows to be 5 inches long. The birds deliver a series of downward kicks with their hind legs that have been known to break bones and cause serious lacerations. With a well-placed strike, the claws can rip open a human belly—or throat.

3. REARING CHICKS IS THE FATHER’S JOB.

Come mating season, a female will breed with several partners. After laying her eggs, she abandons them, at which point the males take over. For the next 50 days or so, each cassowary dad steadfastly incubates his clutch. During this period, an expectant father never leaves the nest, not even to eat or drink; he even enters a strange state where he doesn’t even need to go to the bathroom until the eggs hatch. Once they do, dad spends the next nine months raising and defending his chicks. The male also teaches his growing birds how to forage so that when he eventually chases them away, the youngsters can fend for themselves.

4. CASSOWARIES ARE SURPRISINGLY GOOD JUMPERS.

What’s scarier than a 125-pound modern dinosaur with killer claws? One that can leap 5 feet off the ground. To get the most out of those toe daggers, cassowaries will sometimes jump feet-first at an attacker, with the claws slashing downward in midair. They’re great sprinters to boot, with a top running speed of 30 miles per hour.

5. A SPIKE IS HIDDEN ON EACH WING

Cassowaries are closely akin to ostriches, emus, and kiwis. Like their better-known cousins, the casqued birds have useless vestigial wings. On the tip of each is a small claw that probably serves no purpose.

6. THEY MOSTLY EAT FRUIT.

Wild cassowaries mainly dine on assorted fruits and berries that fall to the ground in the forests they call home. Every day, the typical southern specimen gobbles up roughly 11 pounds’ worth. The big birds also eat plenty of fungi—along with the occasional dead animal for some extra protein.

Cassowaries are prone to hunt down live critters like rodents, snails, and lizards every so often. Poop is yet another item on the menu. Cassowary dung usually contains half-digested fruit, which still has plenty of nutritional value, so these guys are known to devour each other’s droppings—as well as their own. Waste not, want not!

7. THE FUNCTION OF THEIR ODD CRESTS—OR “CASQUES”—IS A MYSTERY

With royal blue necks and shaggy, jet-black feathers, cassowaries look like no other birds on planet earth. Their most distinctive feature is the helmet-like casque that sits above the eyes. A bony protrusion covered with a sheath of keratin (the material which makes up your fingernails), this ornament begins to develop when the bird is around 2 years old. Scientists have long speculated—sometimes wildly—about its purpose. One theory is that casques help the animals push aside forest underbrush. The structures might also be used as a way to attract the opposite sex.

A more interesting hypothesis involves how these birds communicate. Cassowaries emit very deep bellows—the lowest bird calls known to man. Perhaps their casques amplify and broadcast these sounds by acting as a resonation chamber. It’s believed that certain crested dinosaurs (like Parasaurolophus of Jurassic Park fame) produced various calls in the exact same way.

8. THEY’VE BEEN KNOWN TO LIVE FOR DECADES (AT LEAST IN ZOOS).

Naturalists don’t know how old a wild cassowary can expect to get. That said, a few southern cassowaries have reached their 40th birthdays in captivity. Under human care, northern cassowaries can top that figure—one bird reached the age of 48 and another specimen may have been as old as 61 when it died. Meanwhile, the average lifespan for captive dwarf cassowaries is just 26 years.

9. CASSOWARIES HAVE STRANGE GENITALIA.

Both sexes sport a phallic-looking “pseudo-penis” appendage. However, it isn’t connected to any of their reproductive organs internally. During copulation, the male ejaculates through his cloaca—an orifice that lies at the base of the pseudo-penis and not the tip. Males also have what’s usually described as a “vagina-like cavity.” When they aren’t mating, the pseudo-penis is turned inside out and retracted into this orifice.

Such peculiar anatomy has given the cassowary a unique place in New Guinean culture and folklore. For example, the native Mianmin people tell stories about a human woman with a penis who somehow transformed into a cassowary. Another indigenous group, the Umeda, put on a regular ceremony called “ida.” A big event that lasts for two days and nights, the ritual involves a fertility dance which calls for two male dancers who represent a pair of cassowaries. Each player is given a heavy mask and is coated with charcoal from head to toe.

10. AT LEAST ONE UNFORTUNATE HUMAN HAS BEEN KILLED BY A CASSOWARY.

In April 1926, 16-year-old Phillip McLean and his younger brother, Granville, set two family dogs on a wild cassowary near their farm in north Queensland. Things quickly got out of hand. The bird fought back, driving away Granville and one of the canines with a couple of kicks. This didn’t deter Philip or the other dog, as both remained in the fray. Suddenly, the cassowary charged Philip, who fell backwards while trying to flee. Pushing its advantage, it pounced onto the boy and gouged away at his throat. A short while later, the elder McLean died of blood loss. To date, this is the only verified report of a cassowary taking human life.

In 1999, Christopher P. Kofron—then a ranger with the Queensland Parks and Wildlife service—analyzed 150 documented cassowary-on-human attacks. Twenty-two percent of these cases came down to the bird defending itself, its eggs, or its chicks. Another 5 percent were triggered by somebody who’d gotten too close to a cassowary’s food.

The remaining 73 percent of the incidents involved a cassowary that associated people with free meals. For decades, well-meaning Queenslanders have been handing out bananas, watermelons, and other treats to these dangerous animals. This has led many cassowaries to lose their natural shyness around humans in populated areas. Today, feeding a wild one is against the law, but the practice still continues—so if you live in cassowary country, make like you're at the zoo and don't feed the birds.