"The term fossilized is important. It is not the dinosaur bones themselves that paleontologists find, but their stony replicas. Fossil bones are created by the slow replacement of bone molecules with the molecules of minerals in ground water. This process sometimes preserves even the delicate cell structure of the bones. Other times the bones dissolve completely and only their imprint is left on the rocks.
Teeth and bones are the most durable parts of a vertebrate's body. They may survive long after the animal's soft parts have rotted or been eaten. Except for fossilized footprints, skeletal remains are the most common fossils. Unfortunately, few animals ever become fossilized, compared to the millions that lived. Animals seldom die where they can be fossilized. A recently deceased animal that remains above ground will be dissolved by the chemicals in soil and converted into plant food. This is why the bodies of even large animals are seldom found in the woods-and why fossils are most often found in deserts and other "bone-dry" places where there are not many plants. In order for a skeleton to become a fossil, a layer of sediment must quickly cover the body. This prevents the skeleton from being destroyed by other animals or nature. Over the following thousands and millions of years, this sediment hardens into a protective layer of rock, such as shale, siltstone, mudstone, or sandstone. Dinosaur bones could have been covered by sediment in still water, such as at the bottoms of lakes, slow-moving rivers and river deltas, shallow seas, and seacoasts. The sediment could also have been brought by the air, such as sand from dust storms or volcanic ash falls. The places where conditions are right for skeletons to become fossils are only a small percentage of the world's land area at any time. Many species of dinosaurs lived where no fossils could form. Partly for this reason, there are many evolutionary "missing links" between groups of dinosaurs. So there is an incomplete picture of dinosaurs from the fossil record. " Source INTRO TO FOSSILS What is a fossil?- video Different types of fossils- article Fossils article Bill Nye on Fossils-video 15 Unbelievable Fossils-video How do dinos because fossils-video Pompeii Pompeii 2 FOSSILS Fossil Animation What might the vertical piece of rock be? Fossils in sedimentary rock Fossils in layers of rock Types of fossils Mud creates fossils of flesh Jurrasic Park Amber Awesome amber preserves found recently Fossils PPT Types Fossils PPT Fun fossil facts for kids Petrified Fossils- Virtual Museum Molds vs Casts Trace Fossil locations you can visit Carbon Films But what is carbon? Why is carbon important for living things? Fossil Flashcards How dino bones turn to fossils Map of dino bones found on planet Interactive map |
Hannah the HarpistHannah Cotten is a Fifth Grade Science Teacher, and Professional Harpist in Austin, Texas. To view her harp website, click the above link or picture.
Author: Hannah the TeacherMrs. Cotten and her fellow explorers and students co-author this blog. Archives
May 2018
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