Paleontology - An Introduction
What is Paleontology ?
Paleontology is the study of the fossil record. The fossil record tells us the story of ancient life on earth - about the plants and animals that once thrived on the land and sea. It is estimated that 95% of the life forms from earlier times of earth history DO NOT EXIST anymore. The way we learn about them is to study the fossil record they left behind. And we also study the geology - the earth, rocks and minerals - that surround the fossils we find to better understand when they lived.
What are fossils?
Fossils are the remains of very ancient life that has been buried for thousands of years and preserved in a very ancient layer of earth. Some fossils have also been found suspended in fossilized tree sap, like amber.
Fossils have been found from many time periods in the earth's history and can be the record of a tree, a bone, a tooth, and entire skeleton, or a seashell that lived hundreds of thousands of years ago.
How do you find a fossil?
Fossils that were buried many, many millennia ago were covered over the years with layers and layers of sediment - soil, sand, silt, plant debris, other animals. Often this took place on the floor of the ocean, in a lake or bog. Then over long periods of time, the earth's seismic activity - in the form of moving plate tectonics - pushed and pulled the earth's crust. Mountains rose, valleys lowered, and eventually the layers with the fossils were brought back up to the earth's surface. Some earthquakes can even open up layers of fossils never seen before. The ocean or a river can also erode away a cliff face that is a series of layers with fossils.
When an area of ancient earth that contains fossilized remains of early life is exposed to the surface, where we can see it, it is called an outcropping. From these outcroppings scientists and amateur fossil hunters of all ages gather specimens to study and learn from.
You can even buy ancient fossils from professional dealers on the Internet!
Other fossils - like the recent mammoth find on Santa Rosa Island - are exposed as the earths layers shift in the winds and from erosion. We will soon study the nearly complete mammoth skeleton is an excellent example of a line of animals that migrated by water, over the sea, from the mainland to an island and developed their own subspecies unlike any other on the mainland.