Why is the difference between fossils and trace fossils important?

[Daniel Fischer]

First of all I want to make it clear that I know what are trace fossils an I know the difference between fossils and trace fossils, but I feel like I am missing something. In a few posts here on the forum I saw people saying things like "this is not a fossil, maybe a trace fossil" and things like this and I do understand that regular fossils give more information but can anyone please explain to me why it seems like trace fossils are worthless compared to regular fossils? 

 

[Top Trilo]

Fossils are the remains of an organism that was once living, a trace fossil is something that was created by something that was once living . Such as a dinosaur footprint, the footprint was never alive but it was created by something that was, same with coprolites and burrows.

38 minutes ago, Daniel Fischer said:

I do understand that regular fossils give more information but can anyone please explain to me why it seems like trace fossils are worthless compared to regular fossils?

Many times trace fossils give more information. It shows what the animal did when it was alive opposed to how it looks when it died. Trace fossils can inform us about what an animal ate, their size, their speed, etc. And for that reason many trace fossils are valuable and give us a ton of knowledge about a creature we had no idea about. I attached a recent thread of a really cool trace fossil,

 

[Pumpkinhead]

They aren't worthless compared to body fossils. They're our main source of behavioral data in the geologic record 

[Troodon]

There is a clear distinction between the two so they should be identified as such but to infer they are worthless is ridiculous since give us a lot of behavioral info about animals. 

[Fossildude19]

I would say that trace fossils are not as popular collection wise, for a majority of "collectors".  

Many collectors want dinosaur material, teeth, bones, etc. Or they may focus on fish fossils, trilobites, crabs, ammonites, what have you. 

Many collectors just don't find trace fossils aesthetically appealing.

 

People who STUDY fossils, can more easily appreciate the trace fossils for what they represent - the snapshot of a behavior frozen in time. 

[Misha]

Trace fossils can be very important and interesting as others have already said.

 

They tell us about the ecology and behavior of certain organisms which we would only be able to hypothesize about when looking at body fossils exclusively.

They can tell us about the environment in which the organism existed.

 

One difficulty that we have with traces which we may not usually experience with body fossils is pinpointing which organism this trace would have belonged to and sometimes traces are hard to interpret in general.

 

I know @GeschWhat is interested in ichnology and more specifically, coprolites. Maybe she could provide some more insight as well.

[Pumpkinhead]

They're also great paleoenvironmental indicators. Some of my favorite fossils are traces- most of the ones I've collected are Paleozoic feeding traces made by indeterminate animals. A trace fossil defines the base of the Cambrian system (although it may occur diachronously; debates around it are literally a can of worms). 

[jpc]

3 hours ago, Daniel Fischer said:

"this is not a fossil, maybe a trace fossil" 

 

Your confusion comes from the fact that this line is cockamamie .  

[piranha]

6 hours ago, Daniel Fischer said:

... but can anyone please explain to me why it seems like trace fossils are worthless compared to regular fossils?

 

 

The Doyen of Trace Fossils is turning in his grave at the utterance of such blasphemous words!   

 

A new Holocene ichnotaxon has spontaneously appeared:

 

Helicomortichnus seilacheri  ichnogenus nov. et ichnospecies nov.

[GeschWhat]

My FAVORITE subject! First let me say that anyone who thinks "trace fossils are worthless compared to regular fossils" doesn't know COPROLITE about fossil poo!

 

The dictionary definition of a fossil is "a remnant, impression, or trace of an organism of past geologic ages that has been preserved in the earth's crust." So technically, traces are a type of fossil if they are preserved in stone. These are also called ichnofossils.  In all fairness, body fossils (things like like teeth, bones, scales and other animal parts) are important. They tell us what animals looked like. But they are just one small piece in a very large puzzle. Equally or perhaps even more important are trace and plant fossils. They give us a glimpse at things like climate, food sources, and animal activity.  Think of it like this. If there were a statue in the park, it might look nice and be admired for its shape and form. In order to gain the full extent of its significance, one would need to read the plaque beneath. 

 

If you haven't already guessed, coprolites are my favorite type of ichnofossil because they are trace fossils that keep on giving. Many times they contain fossilized body/plant remains (aka dinner) that may not have otherwise survive the fossil record. They sometimes even contain other trace fossils such as bite marks or burrows. They can bring the prehistoric world to life.

 

Let me illustrate with this coprolite:

 

This little gem was given to me by forum member @Ramo that was hunting fossils in a part of Kansas once covered by the Cretaceous Interior Western Seaway. On its surface, it may not look all that special. You can see a vertebrae inclusion (the circular object) on the side and a star-shaped bone (also a vertebra) on the lower end. So here we have a trace fossil that contains at least two body fossils. With a little excavation of the fully digested material on the end, more body fossils are revealed. 

 

So what do you see? It appears that there is a larger, highly digested vertebra on the end. There are at least two medium-sized vertebrae present that appear to be more intact (one on the side and one on the end).  There is one small, rather pristine vertebra that was just under the surface. Since the larger vertebra is much beefier than the smaller ones, you would expect that one to be in better shape. Hmm, what would cause the smallest vertebra to be more pristine than the rest? Here is where the fun starts. One scenario would be that the smaller vertebrae were less digested than the larger vertebra because they were protected in the stomach of the larger fish. It could go something like this:

 

While dinosaurs are roaming the shores, we have a small fish swimming around doing it's fishy business in the Western Interior Seaway. Then along comes a larger hungry fish, which is gulped down by an even larger fish just as it swallowed its dinner. As karma would have it, that large fish's hunger was barely satiated when it too was eaten by an even bigger animal. Can you picture it? This is the gift of coprolite - a trace fossil. Worthless? I think not! This is just one example of how coprolite (the best of all fossils-trace or otherwise ) tells a story.