In the News
Dinosaur-era
feathers trapped
in ancient amber
Preserved plumage reveals
pigment and fine details
STORY ONE
By susan Milius
Bits of filaments and feath- ers trapped in amber 70 to 80 million years ago offer an unusually wide-ranging view
of what late dinosaurs and early birds
were wearing.
The 11 small, amber-bound specimens
found in Canada span an evolutionary
range of late Cretaceous fashion. They
include what appear to be unbranched
filaments — which have been proposed
as the first stage of feather evolution — to
bits of sophisticated, corkscrewy barbs
like those seen in the wettable feathers
of modern diving birds. A team from the
University of Alberta describes the finds
in the Sept. 16 Science.
Such a range has shown up squashed
in rock fossils, but “we’re seeing the
same thing preserved in beautiful 3-D
forms,” says coauthor Ryan McKellar.
“It’s preserved down to the point of having pigment, which opens up the doorway for all sorts of weird and wonderful
investigations.”
© SCIENCE/AAAS
To find the 11 specimens, McKellar
screened more than 4,000 pieces of
amber, collected from the discards of
a coal mining operation near the town
of Grassy Lake in southern Alberta.
McKellar speculates that back in the day,
eleven specimens of amber (two shown) reveal filaments and feathers preserved
from the late Cretaceous period. simple filaments (top) are believed to have
covered dinosaurs. a feather barb (bottom) may have come from an ancient bird.
the area was a salt marsh along the edge
of the great seaway that ran through
what is today western North America.
This trove of amber offers independent evidence that ancient feathers and
even simple filaments did indeed carry
pigment, says evolutionary ornithologist Richard Prum of Yale University. “I
was stunned to see the level of detail preserved,” he says.
How feathers evolved has roused
heated debate in recent years, as pale-
ontologists have reported finding
compressed-rock fossils of dinosaurs
with remnants of filaments or feathers
(see Back Story, Page 6). Well-preserved
dinosaur fossils such as Anchiornis even
show modern-looking feathers with
small barbs branching from a central
shaft. All but the most complicated
asymmetrical flight feathers have shown
up so far in dinosaurs, Prum notes.
