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The biggest dinosaur fossil is Sauroposeidon, which is believed to have stood 60 feet tall and may have weighed as much as 60 tons. That's as tall as a six-story building and as heavy as a nine elephants. 6. The smallest fossils of all are the one-celled organisms that are also the oldest: the blue-green algae. The tiniest dinosaur fossil was found recently in China. Microraptor was the size of a crow (about 12 inches long).
Some animals were quickly buried after their death (by sinking in mud, being buried in a sandstorm, etc). Over time more and more sediment covered the remains. The parts of the animals that didn't rot (usually the harder parts like bones and teeth) were encased in the newly formed sediment. In the right circumstances (when there is no scavengers, quick burial, not much weathering) parts of the animal turned into fossils over time. • After a long time the chemicals in the buried animals bodies underwent a series of changes. As the bone slowly decayed, water infused with minerals seeped into the bone and replaced the chemicals in the bone with rock-like minerals. The process of fossilization involves the dissolving and replacement of the original minerals in the object with other minerals (and or permineralization - the filling up of spaces in fossils with minerals, and /or recrystallization in which a mineral changes its form).
There are lots of different types of fossils including bones, shells, footprints and burrows. Most fossils we find today are creatures that lived their lives in the sea. This is because they were most likely to be buried before all trace of them disappeared!
One thing all fossils have in common is that they are OLD, at least 10,000 years old.
Prehistoric Mammals - Part 1 What Prehistoric Mammals and Modern Mammals all have in common are that they are all warm-blooded with backbones and have fur or hair, and nourish their offspring with milk. They produce their own internal body heat which gives them the ability to move quickly at any given time. We are Mammals! The first mammals appeared about 215-195 Million Years ago, during the Age of the Dinosaurs. It was only after the Dinosaurs went extinct 65 Million Years ago that mammals rose to dominance and began what is called the Age of Mammals or the Cenozoic Era.
Petrification can preserve hard and soft parts and slowly replaces organic material with silica, calcite or pyrite, forming a rock-like fossil. Wood is often found petrified. Some organisms are embedded in Amber (a hardened form of tree sap). This usually preserved insects or pieces of plants. Fossils of imprints may form, like casts of dinosaur footprints. The impressions, in the right circumstances, fill with sediments that fossilize. Most animals did not fossilize, they simply decayed and were lost from the fossil record. Paleontologist’s estimate that only a small percentage of the dinosaurs that ever lived have been or will be found as fossils.
Dinosaur fossils have been found on every continent of Earth, including Antarctica. Fossils help us understand what the dinosaurs were like. Information can be gathered from sources such as fossilized bones, footprints, stomach stones,feces, internal organs, soft tissues, eggs and feathers.
