As regular CFZ-watchers will know, for some time Corinna has been doing a column for Animals & Men and a regular segment on On The Track... particularly about out-of-place birds and rare vagrants. There seem to be more and more bird stories from all over the world hitting the news these days so, to make room for them all - and to give them all equal and worthy coverage - she has set up this new blog to cover all things feathery and Fortean.

Monday, 1 April 2013

True Color of Dinosaur Feathers Debated

Megan Gannon, News Editor
Date: 28 March 2013 Time: 11:41 AM ET

The discovery of microscopic color-making structures in fossilized feathers has recently made it possible for scientists to picture dinosaurs and ancient birds in their natural hues.

But a group of researchers warns we might not be able to paint a Microraptor shimmery black or give the giant penguin a maroon and gray coat just yet.

To reconstruct the elusive color of feathered dinosaurs, scientists have zeroed in on melanosomes, melanin-loaded organelles typically present in the cells of the skin, hair and feathers whose colors (which range from black to brown to reddish) are each associated with a specific geometry. Though the visible color of melanosomes often degrades over time, their preserved size, shape and arrangement and can give some hints about their original color.

But the melanosomes encased in feather fossils today could have a distorted shape that leads scientists to the wrong conclusion about their true color, according to the new study.

Since scientists don't have hundreds of millions of years to watch how feather fossilization takes place from start to finish, Maria McNamara, of the University of Bristol, and her colleagues simulated a long burial by popping bird feathers into an autoclave, subjecting them to temperatures up to 482 degrees Fahrenheit (250 degrees Celsius) and intense pressure, about 250 times that of the atmosphere. The researchers found that the melanosomes shrank under these harsh conditions.


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