Pictured here is not an alligator or lizard skin fossil, for which these are commonly mistaken. It’s an impression of the trunk of a now extinct tree-sized plant, known as a Lepidodendron. It was collected from a stream bed in north Arkansas. The diamond-shaped patterns are sockets where leaves once attached to the trunk. The holes that are just visible within the “diamonds”, are pores through which the plant inhaled carbon dioxide.
Lepidodendron were common in Arkansas during the Carboniferous period (359-299 million years ago). The Carboniferous (or coal-bearing) period is known for lush vegetation. Many of the earth’s important coal deposits were formed from the remains of the rich forests that dominated the land during that time.
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