10/14/2026
Happy National Fossil Day!
This chunk of river mud is a fossil in the making! It’s about 20 years old, so it has a long way to go. When it gets there, it will be both a trace fossil and a body fossil. A trace fossil preserves the activity of organisms, like raccoon footprints. A body fossil preserves the remains of the organism itself, like shells and leaves.
Even now, this slab is useful. It’s one polygonal piece of a mud crack from a riverbank, and it records a rich story. The stream flooded, and when water levels fell again, the mud dried and cracked. Raccoons walked across the mud and left their tracks. Small leaves landed on the surface. Then it rained, and the raindrop pits are still there. A freshwater mussel and some snails are preserved in the side. Closer inspection even revealed fish scales.
Pollen can reconstruct the plant life that grew along the banks. Add insects and microscopic organisms, and we can piece together even more of the community of living things that shared this place.
What do you think the Red River banks are saving right now?