Thousands of Years Before Humans Raised Chickens, They Tried to Domesticate the World’s Deadliest Bird

Fossilized eggs found in rock shelters suggest cassowaries were cohabitating with our ancestors

An photo of a male southern cassowary with two young chicks at a zoo in Amsterdam
Early humans may have eaten late-stage fertilized eggs, known as balut, or raised the chicks for feathers and meat.     Arjan Haverkamp via Wikimedia Commons under CC BY 2.0

The southern cassowary is an enormous, flightless bird native to the forests of New Guinea and Northern Australia. The dinosaur-like creature has glossy, jet-black feathers and a bright blue neck with a vibrant scarlet wattle dangling from its neck. They also have three-toed, razor-sharp talons that can inflict severe fatal injuries with a roundhouse kick when provoked, earning them the title "world's deadliest bird," reports Asher Elbein for the New York Times.

While one should certainly be wary around a cassowary and its dagger-like claws today, a new study found that humans may have raised the territorial, aggressive birds 18,000 years ago in New Guinea, making them the earliest bird reared by our ancient ancestors, reports Katie Hunt for CNN. The research was published on September 27 in the Proceedings of the National Academy of Sciences

"This behavior that we are seeing is coming thousands of years before the domestication of the chicken," says study author Kristina Douglass, a Penn State archaeologist, in a statement. "And this is not some small fowl, it is a huge, ornery, flightless bird that can eviscerate you. Most likely the dwarf variety that weighs 20 kilos (44 pounds)."

Researchers excavating two rock shelters in New Guinea found 1,000 fragments of fossilized cassowary eggshells. To get a closer look at the ancient shell pieces, the team used three-dimensional imaging, computer modeling, and studied egg morphology of modern cassowary eggs and other birds, like emus and ostriches. Using carbon dating, the eggs are estimated to be 6,000 to 18,000 years old. For comparison, chicken domestication occurred no earlier than 9,500 years ago, per CNN. 

Early humans may have foraged for eggs to raise the chicks for feathers and meat, or they may have harvested and ate late-stage fertilized eggs, known as balut, reports Joanna Thompson for Live Science. Balut is still eaten today as street food in some parts of Asia, per a statement.

"What we found was that a large majority of the eggshells were harvested during late stages," says Douglass in a statement. "The eggshells look very late; the pattern is not random. They were either into eating baluts, or they are hatching chicks."

Cassowary eggs are bright, pastel green, and males incubate the eggs for about 50 days in a leafy nest on the ground. Collecting the eggs would have been challenging, however. The birds fiercely guard their nests in dense foliage hidden out of sight. Ancient humans would have needed to know exactly where the large birds were nesting, which indicates early humans were more capable of sophisticated intelligence than previously thought, per the New York Times.

"It suggests that people who are in foraging communities have this really intimate knowledge of the environment and can thus shape it in ways we hadn't imagined," Douglass tells the New York Times.

Many of the eggshells had burn marks, which indicates some eggs were cooked. However, enough eggshells were found without char marks to determine some late-stage eggs were purposely left to hatch, meaning our ancestors may have been raising cassowary chicks, according to the statement. Despite the aggressive nature of adult cassowaries, young chicks would have been easy to raise. Like geese, cassowary chicks imprint on the first adult bird, person or animal they see, per CNN.

Today, cassowary feathers are still collected for ceremonial wear, and cassowary meat is considered a delicacy in New Guinea.