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Check out this video to learn more about the Coon Creek Formation in Tennessee!

Transcript:
Water running

The Coon Creek formation is a geological formation that extends all the way from western Tennessee to northeast Mississippi, but its most famous and well preserved fossils are found at the Coon Creek Science Center’s bed, in Adamsville Tennessee just 2 hours east of Memphis.
The site features over 700 different fossilized species ranging from clams, crabs, mollusks, snails, and even Mosasaurus fossils!

But what makes Coon Creek such a great fossil site? To understand, we must look back in time to around 70 to 80 million years ago during the Late Cretaceous Period.

Today, we are familiar with the East Coast of the United States looking like this, with Coon Creek being located here, far from the shore and Florida a clear peninsula, however, this was not always the case. During the Cretaceous period, the sea levels were much higher than the present day. The Western Interior Seaway ran all the way across the Western United States, and the Mississippi Embayment covered most of the South-East, including the Western portion of Tennessee that Coon Creek resides in.

This area of Tennessee would have been a relatively shallow marine environment, perfect for organisms like clams, crabs, oysters, small fish, and others, hence the reason why so many of their remains were fossilized. But aside from abundance, there are more reasons why Coon Creek fossils are so well preserved. Over time, the sea level receded, allowing for the collection of marine sediments at that part of Tennessee that covered the metazoan. These sediments would have been very small, clay-sized particles, creating an airtight layer between the sea organisms and the rest of the environment.

This factor might not seem like a big deal, but actually makes the fossils at Coon Creek particularly special. Because the clay created such a great protective layer, the fossils at Coon Creek are preserved in their original state, which is a rare occurrence. Typically, fossils have recrystallized or have only preserved the indentation of the creature that died, but the Coon Creek fossils preserve the organisms in their original state, sometimes even capturing soft tissue in the rock record. The clay preserves amino acids, microfossils, and even nacre, or the shiny, mother-of-pearl material found in the inside of shells!

The fossils are preserved in such detail that in certain bivalve clams, the muscle scars and hinge teeth marks of the clam’s anatomy are easily discernable, and sometimes both halves of the clam have even been kept together!

So why do we care so much about well-preserved fossils and keeping track of them? The more detailed information we gather about life throughout Earth’s history, the better we can get at understanding Earth’s past, the environments that existed, and how life interacted with and was affected by those environments. Fossils help scientists understand these relationships and allow them to create more accurate depictions of the world before humans, further research about evolutionary and biodiversity changes, and even give better explanations for processes that occur today. Without well-preserved fossils, we wouldn’t know about the coral reefs that once spanned hundreds of miles across North America, we wouldn’t know about the gigantic bugs from 300 million years ago, the dinosaurs, or even the first signs of life on the planet.