Australian-Geographic-Magazine-September-Octobe..

FOSSILS, FEATHER AND SEM IMAGES: IVPP, UNIVERSITY OF BRISTOL; ILLUSTRATION: LIDA XING; FOSSIL FEATHER: MUSEUM VICTORIA

Melanosomes are tiny packages

of pigment inside feathers and

hair in living birds and mammals,

and are responsible for making

your hair black, brown, blond or

ginger. It turns out that melano-

somes are made from keratin, an

incredibly tough protein, and

under the right conditions can

survive even for hundreds of mil-

lions of years in fossils. Two types

of the pigment melanin are

found in the feathers of modern

birds and they are packed in

different shaped melanosomes.

74 Australian Geographic

Fossil clues to the colour of feathers

By studying the fi ne details of incredibly preserved fossil feathers,

scientists are able to look for structural clues to the original colours.

When you look at the feathers of a living bird under a

high-powered scanning electron microscope (SEM) you

can see melanosomes of different types. For example,

the feather of an Australian zebra fi nch (left) has

spherical phaeomelanosomes 1 in the orange part

of the feather and sausage-shaped eumelanosomes 2

in the black parts of the feather.

MODERN BIRDS

CONFUCIUSORNIS

MELANOSOMES

2 Eumelanin

Comes in black and brown

varieties, and, depending on the

concentration, can also produce

light brown, blond and grey col-

ours. This pigment is packaged in

sausage-shaped eumelanosomes.

1 Phaeomelanin

Produces reddish colours, and is

the pigment in ginger hairs in

humans. This pigment is packaged

in spherical phaeomelanosomes.

Confuciusornis is a 125-million-year-old bird from the Early

Cretaceous of Liaoning Province in north-eastern China. Experts

led by Professor Mike Benton at the University of Bristol, UK, and

Zhang Fucheng at the Institute of Vertebrate Paleontology and

Paleoanthropology in Beijing, China, used an SEM to look at its

fossilised feathers. This revealed phaeomelanosomes 1 and

eumelanosomes 2 and indicated this early bird may have had black,

grey and red-brown feathers, perhaps something like a zebra fi nch.

1

2

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