The badlands of southern Alberta are a treasure-trove for
dinosaur investigators. The absence of plant growth and the
soft sandstone easily expose the fossilized bones of prehistoric
animals.
Alberta's badlands region is where, in 1996, convincing evidence
was discovered to support the theory that modern birds are
the direct descendants of dinosaurs.
Dr. Phil Currie of the Royal Tyrrell Museum does his research
from the field station in Dinosaur Provincial Park in the Badlands.
He has discovered a fossilized dinosaur with a beak like a
bird's. The dinosaur was a familiar species that looked very
much like a modern ostrich. But this one was the first that
had retained the animal's beak, a soft structure that does
not easily fossilize.
Alberta, 65-90 million years ago, was as warm, moist, and
sandy as Florida is today. It was an ideal place for dinosaurs
to live, and for their bones to be preserved when they died.
Dinosaur fossils originated when bones were buried under protective
covers of sand or mud. Over thousands of years, the sand or
mud hardened into porous rock. Water gradually dissolved the
bones, creating cavities in the rock. As water flowed through
the cavities, it left behind mineral deposits that eventually
filled the cavities completely and became fossils.
Soft material, such as beaks, usually decayed before the fossilization
process could begin. The unusual find of a dinosaur fossil
with a beak was the missing link that paleontologists had been
seeking to prove what most now believe: dinosaurs never did
become extinct. Instead, dinosaurs evolved to become more efficient
animals that could fly to find food and to escape their enemies.
"Personally, I think dinosaurs are alive and doing extremely
well," declared Currie. He said 90 percent of his professional
colleagues would now agree that "birds are the direct
descendants of dinosaurs."
Birds and dinosaurs share about 125 physical characteristics. "If
you pluck the feathers off the first bird, the archaeopteryx,
it's a dinosaur," noted Currie.
The theory that birds evolved from dinosaurs first emerged
150 years ago, but was buried under the general belief that
dinosaurs all died off in some environmental disaster, such
as the crash of a moon-size meteorite.
Alberta's badlands have delivered key evidence to support
the revived belief that dinosaurs did not die off at all, but
evolved into birds.
In this view, the disappearance of the prehistoric dinosaur
was not the failure of a species. Instead, dinosaurs may represent
a monumental triumph of evolution.
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