Fossil Identification And Classification

Fossil identification can be a challenging proposition. Often a small detail is all that seperates one species from another. Still overall classification system is not so difficult to understand.

Fossils of animals are classified, as are living specimens, by observing the body structures and functions. While there are a few unique challenges in classifying fossils, the basic scheme of organization is the same. Going one step at a time can make fossil identification possible for anyone.

Biological classification systems have a long history. Aristotle, working in ancient Greece, sought to classify animals by comparing the essence of the species. His system was a detailed system that included descriptions of the body. He believed that all species related to earth, air , fire, and water and classified accordingly..

More than a few centuries later, Carolus Linnaeus created another organizational system. His system was hierarchical, with increasingly detailed separations among members of the groups. Today, scientists use more or less the same system.

Living organisms are grouped according to their similar characteristics. Therefore, animals are in a group separate from plants, separate from bacteria, etc.

Breaking down the animal kingdom, the phylum level attempts to put animals into broad categories of similar body types. Phylum Porifera contains animals whose bodies are a collection of cells that loosely come together and are filled with many openings or pores. An example of this is the sponge. Phylum Mollusca all have soft bodies, no internal skeleton, and, often, are able to make shells. Phylum Echinodermata all have shells with a bumpy surface, or “spiny skin” as their name implies.

Subsequent groupings are formed on the same basis: similarity of features, even when the features are minute or on a chemical level.

The classification divisions are as follows:

Getting back to fossil identification…fossils belong to the same groups as modern-day animals. A Trilobite had an exoskeleton, jointed appendages (legs primarily) and a body that had distinct sections. All these features make it a member of the Phylum Arthropoda. The crinoid looked like a delicate plant with a “flower” at the end of a long stalk. But the stalk and the flower, were actually an animal that had bumpy skin—so it fits into the Phylum Echinodermata.

Paleontologists look at minute details to determine further fossil identification and classification. With the trilobites, they consider the construction of their eyes, the variation in the segments of the body, the quality of the exoskeleton-whether it has a smooth surface or rough-the presence of antennae, and even the internal organs! Definitely a job for experts, but with a little practice, you will begin to call them by smaller group names such as Phacops or Agnosta!

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Here are some recent submissions we have identified.

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re submitting  
Found out that we were swimming in lake Wilson, Wilson Kansas when this was found. sandstone.

Don't know? 
I was given this by a friend who got it from a friend. I really want to know what it is, can you help me please.

feathers or leafs?  
I Showed my friend the fossil I send y'all last night and she got this out of her sewing kit to share, she found it in the woods as a kid could not remember …

flower or bug 
found swimming in Kansas, Seems to be an imprint of a flower or smashed bug in sandstone,the stone its in is vary thin.

What is it 
Found at Lake Whitney, Texas

Shark teeth? 
Found it In the Lake Ontario regions. It have white stuff all over

Came across this find and would like to know what it possibly could be

Saudi Arabian Desert Fossil 
Found this outside of Riyadh, Saudi Arabia in the early 80's.

not sure what I found 
while looking for geodes I stumbled on this


Phylum Arthropoda? 
I don't really know what it is. I took Geology, but I got a really bad grade, ha ha! Just because I'm not good at geology,but I really am fascinated by …

I found it in the clackamas river in Oregon. That's all I know about it.

Got no idea. 
Bought a box of rocks and found it in box. It's about the size of the Palm of your hand. I would love to find out what kind of stone it is.

gem fossil 
found out of a iron sandstone concerstion out of colorado the soft bodie parts are replace by minaral i belive it pirite and siderite my studieds lead …

Fish ribcage 
My father found this in Warsaw Kentucky, we are struggling to identify this creature.

rock wall finds  
the small dark piece is smooth & has a define ridge on it, the longer piece is crumbly & fragile i thought maybe bark but it's probably something

Wellington unknown #1 
This fossil was found in northern Colorado, close to the foothills of the Rockies. It was found in a field that has been farmed for years, but has seen …

Hi I found this large rock in the 1950s as a child in Staten Island NY. It had a small imprint of a shell on the outside. I recognized it as a fossil …

not sure 
found it by a river near where i live

We are not sure. I think possibly an egg ? 
Michelle found this at a near by lake. It was imbedded in soft rock with other small fossiles

We think its a tooth from a fish 
We were walking on the shore of a lake, which was very low due to lack of rain, in the sand we found numerous teeth like this one and many sharp teeth …

I thought it might be teeth, but Michelle seems to think it is a tube of some type of squid 
Michelle and I were exploring an abandoned quarry and she found these. Michelle is the rock hound here. Her collection is amazing. I hope we can share …

i found it at a thrift store for fifty cents and i thought it was some kind of fossil material and was hoping someone could tell me what it is

Linda's bone 
I dug up someone's discarded rock collection in an empty field in Fresno, CA. 10 years ago. There were fossils, crystals and abalone shells. Had to dig …

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This was located on a shingle beach at Seaford East Sussex today.

Spencer's Fossil 
I know nothing much about such things and seek an opinion of the item in hand. It was found in Missouri and know one so far has any real ideas. Please …

Egg Shape 
Found in a small creek in Caldwell County, Missouri. I haven't found anything similar in the creek.

Dads Rock 
Hi, My Dad found this rock/fossil in Arizona and gave it to me. I am so curious as to what it is. Your attempt to identify will be greatly appreciated. …

Not even sure it is a fossil 
Found in shale bank on the beach.

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There are some great website for viewing photos of the different species. Here are just a couple that show off many different types from the same order:Per Hansson has a fabulous collection of trilobite pictures and try Geoscience Enterprises for fossil identification of crinoids.

Of course, there are lots of books that will help you with fossil identification of your favorite fossil. These are some that we use. I recommend them because they are easy to read, inexpensive, and they are readily available.

1. Simon & Schuster's Guide to Fossils.
2. Field Guide to North American Fossils from the Audubon Society.
3. For children: An Usborne Guide Rocks & Fossils

Armed with some great resources and your growing interest, you’ll be impressing your friends as you introduce them to your collection’s specimens by name. Be careful, though, they just might think you need to find some modern animal friends to keep you company!

For help with fossil identification click this link

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