Do Bones Ever Decay?

Do bones ever decompose? If they do, how come we have dinosaur fossils from millions and millions of years ago? Well, we can guarantee it doesn’t have anything to do with additives or preservatives. To begin, they do decay! The process is much slower than in other natural materials, but they decompose just the same. The reason we have dinosaur bones from so long ago is that they aren’t bones at all. They’re fossils!

How Fossils Are Formed

So how do we end up with fossils that look exactly like dinosaur bones? Well, first, sadly, a dinosaur has to die and leave its bones behind. These bones are then covered up by something like mud, tar, or ice. This makes a cast of the bone: a hard shell around it. Then, the old bone decomposes, leaving an empty space in its exact shape. Just as a mold fills with material, this space fills with a naturally occurring material. This is how we end up with fossils today! (This is why the La Brea tar pits are such a hotspot  for fossils!) 

What Are Fossils Made Of?

Fossils are almost exclusively made of rock, which is how they last so long. This rock is made from the minerals in groundwater that, over millions of years, fill the space left behind by the bones.

Artificial Fossils In Museums?

Believe it or not, this process is repeated in a lab to ensure fossils can be seen in museums all around the world. Real fossils are too precious and delicate to be put on display, so a mold is made from the original fossil and presented for everyone to see. Don’t be disappointed, though, because these double-cast fossils are just as mighty as the original bones!

It’s All Calcium

Whether it’s bones, teeth, or any other organic material, it will all eventually decay. So remember to drink your milk! Maybe if the dinosaurs drank their milk, we’d have more fossils.

Fossils are just one way to look at the rich and complex history of the Earth. There are so many signs of the Earth’s past all around you. Next time you step outside, think about what dinosaurs may have lived where you are now.