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The REALLY Ancient SouthWest
To best understand the REALLY ancient history of the Southwest, we need
to turn our attention from human time to earth time.
Earth Time is a very long story covering about 4.6 billion years of geologic
change, the first signs of life, plant growth, and animal species developments.
Inside that 4.6 billion year story, the Human Time of building settled
villages, raising crops and developing societies began about 12-14,000
years ago. These accomplishments have been built upon to shape our own
society today, but we were not the first species to live in groups, raise
children, travel in families, and hunt for food.
 
One of the most remarkable parts of the earth's story is Dinosaur Time.
Around the world on all continents, Dinosaur bones have been found and
marveled over since 1600 BC when the Chinese first discovered what they
called 'Dragon' bones and teeth. The first peoples in Colorado manufactured
some of their chipped stone tools from fossilized dinosaur and mammal
bone, and fossilized wood. Trade beads containing segments of fossils
were worn for adornment. In the 1870s and 1880s, scientists exploring
the Southwest discovered more of these 'Dragon' bones, which by then had
come to be called Dinosaurs, meaning Fearfully-Great Lizard. We now know
that the Ancient Southwest was home to these fascinating creatures for
175 million years, spanning 65-240 million years ago. But not all dinosaurs
were fearfully huge, nor was all gigantic life during the period a 'dinosaur'.
In recent years, scientists in California have discovered a huge dinosaur-sized
ocean-swimming amphibian
who lived during the same Mesozoic period,
paddling along the coastline of the Pacific which then lapped up against
what is now the Sierra Nevada.
If you think about it, if dinosaurs roamed the earth 65-240 million years
ago, this means they were here for MILLIONS of years and accomplished
a system of very successful adaptation and survival. When Arlington Woman
lived on Santa Rosa Island off the shore of California 13,000 years ago
(making her the oldest yet known human inhabitant of the United States),
she probably was in the company of pygmy mammoths while saber tooth tigers
and dire wolves roamed the mainland. But
even these prehistoric beasts lived millions of years after the Dinosaurs
of the Ancient Southwest. In fact, their home along the west coast was
actually under the sea for the entire Mesozoic Era of Dinosaur Time.
During the Mesozoic, much of Arizona and Nevada were actually probably
close to being oceanfront property!
And while the millions of years of Dinosaur Time are truly amazing, perhaps
even more astounding is the millions of years of Geologic Time that surrounds
their lives. The Grand Canyon, one of the great marvels of the earth's
story, not only contains rocks and fossils from the time of the dinosaurs,
it contains rock strata (layers) that date back to 1.7 BILLION years ago.
1.7 billion years ago the rock of the Vishnu Schift in the Inner Gorge
of the Canyon was formed, and in more 'recent' geologic time, many layers
above, the Kaibab limestone formation was laid down 250 million years
ago ... even then, Dinosaur time was just getting ready to begin. The
more recent layers in the Grand Canyon are volcanic lava and ash from
eruptions 1 million years ago … long ago in Human Time, but very recent
in Earth Time.
Dinosaurs and dramatic canyons are not the only evidence we have of what
life was like in the REALLY Ancient Southwest. During the 240-65 BC Mesozoic
Era of Dinosaur Time, the colorful layers of the Painted Desert were also
being formed and the remarkable plant and mineral interactions that created
what is now the Petrified Forests began. Plants began to live in the Southwest
that had never existed before - the prehistoric cycads, pine forests,
giant sequoias, and giant ferns - all ancestors of plants we still see
today around the world.
Now that we are learning to think in Earth Time, let's explore the REALLY
Ancient Southwest to better understand the geology, geography, plants
and creatures that have shaped and inhabited in this region for millions
- make that billions - of years. And let us also meet the scientists whose
work is to help us better understand the scope and details of these distant
times.
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