This chicken has black bones, organs, and meat: Here’s why.

There are four breeds of chicken that have black insides, and all of them possess the same genetic mutation. A scientist explains how it came about.

The Ayam cemani chicken may be the most deeply pigmented creature on earth. Not only are the bird’s feathers, beak, comb, tongue, and toes a striking, blue-ish black, but so are its bones.

Even the chicken’s meat looks like it has been marinated in squid ink.

Interestingly, the cemani, which is found in Indonesia, is just the most extreme example of what scientists call dermal hyperpigmentation. Another breed, known as the silkie because of its soft, hair-like feathers, also sports hyperpigmented skin and tissues, as do the black H’Mong chickens of Vietnam and the svarthöna of Sweden.

Scientists call the condition fibromelanosis.

“We have evidence that it is a complex rearrangement in the genome,” says Leif Andersson, a geneticist at Uppsala University in

DON'T MISS THE REST OF THIS STORY!
Create a free account to continue and get unlimited access to hundreds of Nat Geo articles, plus newsletters.

Create your free account to continue reading

No credit card required. Unlimited access to free content.
Or get a Premium Subscription to access the best of Nat Geo - just $19
SUBSCRIBE

Read This Next

Is banning fishing bad for fishermen? Not in this marine reserve
SeaWorld allegedly violated the Animal Welfare Act. Why is it still open?
'World’s worst shipwreck' was bloodier than we thought

Go Further

Subscriber Exclusive Content

Why are people so dang obsessed with Mars?

How viruses shape our world

The era of greyhound racing in the U.S. is coming to an end

See how people have imagined life on Mars through history

See how NASA’s new Mars rover will explore the red planet

Why are people so dang obsessed with Mars?

How viruses shape our world

The era of greyhound racing in the U.S. is coming to an end

See how people have imagined life on Mars through history

See how NASA’s new Mars rover will explore the red planet

Why are people so dang obsessed with Mars?

How viruses shape our world

The era of greyhound racing in the U.S. is coming to an end

See how people have imagined life on Mars through history

See how NASA’s new Mars rover will explore the red planet