In the last post I mentioned trace fossils. I looked back to link to the post on trace fossils versus body fossils only to find there isn't one. So: Body fossils are the kinds of fossils that most people think of when the think of a fossil. The remains of the organism. Trace fossils are the remains of the ACTIVITY of an organism. So this footprint. Trace fossil
The dinosaur bone. Body fossil.
Trace fossils are very useful. Every organism (with the sort of exception of things that molt) have the potential to leave exactly one complete body fossil. And usually you find scattered stuff like the bone above. But an organism could leave thousands of trace fossils, so they are very common. Trace fossils are given generic and specific names but do not form higher order linean groups (families, kingdoms etc...). The foot print above belongs to the ichnogenus (ichno- is a prefix for trace fossil) Acrocanthosaurus.
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