Why Are There Sea Shells In Wyoming?

As many of you who listen to my morning radio show know, I grew up on an island. It is a beautiful place full of shelly beaches. Not sandy beaches, but full of sea shells. In fact, Sanibel Island had been called one of the best shelling islands on earth.

I moved to Wyoming 16 years ago.

While exploring the state I came across an area known for its preserved dinosaur tracks.

The tracks were interesting enough, but while poking around down in what was an old creek bed, I was shocked to find sea shells. Lots of them.

Why were they here?

Why so plentiful, like the beaches of Sanibel?

I did a little research and found that during the Precambrian, Wyoming was covered by a shallow sea.

That water world that was Wyoming lasted a good long time.

During the early part of the Paleozoic, the sea was still here.

Over time, as the climate continued its natural cycle of endless change, the Western Interior Seaway receded.

Areas that were once the bottom of the sea were left exposed.

It was a vast area that covered parts of Canada, South Dakota, Colorado, Nebraska, Minnesota, New Mexico, and Wyoming.

What I was holding in my hand in that ancient creek bed were the shale fossilized shells of ammonites.

They are the extinct ancestors of the famous spiral-shaped nautilus seashell.

There were also more rounded shells and something that looked like a small clam shell.

I can identify much of what I found on the beaches of my childhood.

What I was holding here were their ancestors, millions of years before.

That is why they looked similar, but not exactly the same.

It never ceases to amaze me what can be found in Wyoming, when we take a moment to stop and poke around in the ground.